Meteorological factors and risk of scrub typhus in Guangzhou, southern China, 2006–2012
2014-01-01
Background Scrub typhus is becoming the most common vector born disease in Guangzhou, southern China. In this study, we aimed to examine the effect of weather patterns on the incidence of Scrub typhus in the subtropical city of Guangzhou for the period 2006–2012, and assist public health prevention and control measures. Methods Scrub typhus reported cases during the period of 2006–2012 in Guangzhou were obtained from National Notifiable Disease Report System (NNDRS). Simultaneous meteorological data including temperature, relative humidity, atmospheric pressure, sunshine, and rainfall were obtained from the documentation of the Guangzhou Meteorological Bureau. A negative binomial regression was used to identify the relationship between meteorological variables and scrub typhus. Results Annual incidence rates of scrub typhus from 2006 to 2012 were 3.25, 2.67, 3.81, 4.22, 4.41, 5.12, and 9.75 (per 100 000) respectively. Each 1°C rise in temperature corresponded to an increase of 14.98% (95% CI 13.65% to 16.33%) in the monthly number of scrub typhus cases, while a 1 hPa rise in atmospheric pressure corresponded to a decrease in the number of cases by 8.03% (95% CI −8.75% to −7.31%). Similarly, a 1 hour rise in sunshine corresponded to an increase of 0.17% or 0.54%, and a 1 millimeter rise in rainfall corresponded to an increase of 0.05% or 0.10%, in the monthly number of scrub typhus cases, depending on the variables considered in the model. Conclusion Our study provided evidence that climatic factors were associated with occurrence of scrub typhus in Guangzhou city, China. Temperature, duration of sunshine, and rainfall were positively associated with scrub typhus incidence, while atmospheric pressure was inversely associated with scrub typhus incidence. These findings should be considered in the prediction of future patterns of scrub typhus transmission. PMID:24620733
Epidemiologic characteristics of scrub typhus on Jeju Island.
Lee, Sung Uk
2017-01-01
Scrub typhus is the most common febrile disease in Korea during the autumn. Jeju Island is the largest island in South Korea and has a distinctive oceanic climate. This study aimed to identify epidemiologic characteristics of scrub typhus on Jeju Island. From January 2011 to December 2016, 446 patients were diagnosed with scrub typhus on Jeju Island. The patients' personal data and the environmental factors that might be related to scrub typhus were investigated and retrospectively analyzed. The median age of the patients was 58-years-old (range, 8 to 91) and 43% of them worked in the agricultural, forestry or livestock industry. Regardless of their job, 87% of the patients had a history of either working outdoors or of other activities before developing scrub typhus. The south and southeast regions of Jeju Island, especially Namwon-eup, showed the highest incidence of scrub typhus. Workers in mandarin orange orchards seemed to be the highest risk group for scrub typhus infection. Scrub typhus on Jeju Island showed unique characteristics. To efficiently prevent scrub typhus, each year individual regional approaches should be developed based on the epidemiologic characteristics of the disease.
Associated factors and clinical implications of serum aminotransferase elevation in scrub typhus.
Su, Tung-Hung; Liu, Chun-Jen; Shu, Pei-Yun; Fu, Yang-Hsien; Chang, Chi-Hsien; Jao, Ping; Kao, Jia-Horng
2016-12-01
Timely diagnosis and prompt treatment can reduce the complications of scrub typhus. It is thus important to find easy laboratory tests to help in the diagnosis, especially in patients without eschar at initial presentation. Because serum aminotransferase elevation is common in scrub typhus, its associated factors and clinical implications need further investigations. We conducted a retrospective study in Kinmen, Taiwan, to collect clinically suspected scrub typhus patients notified to Taiwan Centers for Disease Control for confirmation during 2005-2010. Scrub typhus was diagnosed and Orientia tsutsugamushi was genotyped by serological or molecular assays. The laboratory data and clinical information were recorded for analysis. Overall, 344 suspected scrub typhus patients were reported to Taiwan Centers for Disease Control and 288 of them were certified scrub typhus. Scrub typhus patients had significantly more thrombocytopenia, serum aminotransferase elevation (76% vs. 54%, p = 0.001), higher frequency of fever, eschar, and lymphadenopathy, compared with nontyphus patients. Hepatic dysfunction in scrub typhus was associated with older age, longer fever duration, and absence of lymphadenopathy, but seemed to be unrelated to the rickettsial genotypes. Multivariate analysis showed that serum aminotransferase elevation (odds ratio: 3.75; p = 0.003; 95% confidence interval: 1.56-9.01) independently predicted scrub typhus. Furthermore, in suspected scrub typhus patients without eschar, 92% of true typhus patients had serum aminotransferase elevation compared with the nontyphus ones (odds ratio: 6.47; p = 0.028, 95% confidence interval: 1.23-34.11). Hepatic dysfunction in scrub typhus patients is associated with older age, longer fever duration, and absence of lymphadenopathy. Serum aminotransferase elevation can aid in the diagnosis of scrub typhus, especially in suspected patients without eschar. Copyright © 2014. Published by Elsevier B.V.
Epidemiologic characteristics of scrub typhus on Jeju Island
2017-01-01
OBJECTIVES Scrub typhus is the most common febrile disease in Korea during the autumn. Jeju Island is the largest island in South Korea and has a distinctive oceanic climate. This study aimed to identify epidemiologic characteristics of scrub typhus on Jeju Island. METHODS From January 2011 to December 2016, 446 patients were diagnosed with scrub typhus on Jeju Island. The patients’ personal data and the environmental factors that might be related to scrub typhus were investigated and retrospectively analyzed. RESULTS The median age of the patients was 58-years-old (range, 8 to 91) and 43% of them worked in the agricultural, forestry or livestock industry. Regardless of their job, 87% of the patients had a history of either working outdoors or of other activities before developing scrub typhus. The south and southeast regions of Jeju Island, especially Namwon-eup, showed the highest incidence of scrub typhus. Workers in mandarin orange orchards seemed to be the highest risk group for scrub typhus infection. CONCLUSIONS Scrub typhus on Jeju Island showed unique characteristics. To efficiently prevent scrub typhus, each year individual regional approaches should be developed based on the epidemiologic characteristics of the disease. PMID:28823118
Borkakoty, Biswajyoti; Jakharia, Aniruddha; Biswas, Dipankar; Mahanta, Jagadish
2016-01-01
Scrub typhus and leptospirosis are bacterial zoonotic disease causing high morbidity and mortality. The seasonal outbreak of pyrexia is common in Arunachal Pradesh (AP); many times the disease remains undiagnosed. An outbreak of pyrexia of unknown origin (PUO) occurred in Longding district of Arunachal Pradesh in 2013, with 108 deaths, which was investigated to elucidate the cause of illness. Blood samples from the affected region with acute pyrexia were collected, and screened for the malaria parasite, scrub typhus IgM and leptospira IgM. Scrub typhus IgM was reactive in 97% (30/31), and 25% (8/31) cases were co-infected with leptospira. Incidentally, scrub typhus reactive (67%) and leptospira co-infection (62.7%) were higher in females. Record of previous 3 years (2011-2013) from Longding, Community Health Centre showed an increase in indoor pyrexia cases by 2-fold or more during October and November. The present study is the first report of co-infection of scrub typhus with leptospirosis from Northeast India. Medical officers in this region should take scrub typhus and leptospirosis in their differential diagnosis of patients with PUO for early diagnosis and effective treatment.
Seto, J; Suzuki, Y; Nakao, R; Otani, K; Yahagi, K; Mizuta, K
2017-02-01
Climate change, by its influence on the ecology of vectors might affect the occurrence of vector-borne diseases. This study examines the effects of meteorological factors in Japan on the occurrence of scrub typhus, a mite-borne zoonosis caused by Orientia tsutsugamushi. Using negative binomial regression, we analysed the relationships between meteorological factors (including temperature, rainfall, snowfall) and spring-early summer cases of scrub typhus in Yamagata Prefecture, Japan, during 1984-2014. The average temperature in July and August of the previous year, cumulative rainfall in September of the previous year, snowfall throughout the winter, and maximum depth of snow cover in January and February were positively correlated with the number of scrub typhus cases. By contrast, cumulative rainfall in July of the previous year showed a negative relationship to the number of cases. These associations can be explained by the life-cycle of Leptotrombidium pallidum, a predominant vector of spring-early summer cases of scrub typhus in northern Japan. Our findings show that several meteorological factors are useful to estimate the number of scrub typhus cases before the endemic period. They are applicable to establish an early warning system for scrub typhus in northern Japan.
Hemorrhagic Transformation of Scrub Typhus Encephalitis: A Rare Entity.
Kim, H-C; Yoon, K-W; Yoo, D-S; Cho, C-S
2015-12-01
Central nervous system (CNS) involvement of scrub typhus infection is well known. Most CNS involvement of scrub typhus infection present as meningitis or encephalitis. We report on a patient suffering from hemorrhagic transformation of intracranial lesions caused by Orientia tsutsugamushi. A 53-year-old female farmer who was infected by scrub typhus was treated with doxycycline and recovered from the systemic illness. However, headache persisted. Brain radiologic studies revealed acute intracranial hemorrhage and enhancing lesion, which implied a CNS involvement. Hemorrhagic transformation of encephalitis by scrub typhus is very rare complication and to our best knowledge, this is the first report of hemorrhagic transformation of scrub typhus encephalitis. Clinician should consider the possibility of hemorrhagic transformation of encephalitis in cases of scrub typhus infection.
Climate variability, animal reservoir and transmission of scrub typhus in Southern China
Li, Xiaoning; Ma, Yu; Tao, Xia; Wu, Xinwei
2017-01-01
Objectives We aimed to evaluate the relationships between climate variability, animal reservoirs and scrub typhus incidence in Southern China. Methods We obtained data on scrub typhus cases in Guangzhou every month from 2006 to 2014 from the Chinese communicable disease network. Time-series Poisson regression models and distributed lag nonlinear models (DLNM) were used to evaluate the relationship between risk factors and scrub typhus. Results Wavelet analysis found the incidence of scrub typhus cycled with a period of approximately 8–12 months and long-term trends with a period of approximately 24–36 months. The DLNM model shows that relative humidity, rainfall, DTR, MEI and rodent density were associated with the incidence of scrub typhus. Conclusions Our findings suggest that the incidence scrub typhus has two main temporal cycles. Determining the reason for this trend and how it can be used for disease control and prevention requires additional research. The transmission of scrub typhus is highly dependent on climate factors and rodent density, both of which should be considered in prevention and control strategies for scrub typhus. PMID:28273079
Climate variability, animal reservoir and transmission of scrub typhus in Southern China.
Wei, Yuehong; Huang, Yong; Li, Xiaoning; Ma, Yu; Tao, Xia; Wu, Xinwei; Yang, Zhicong
2017-03-01
We aimed to evaluate the relationships between climate variability, animal reservoirs and scrub typhus incidence in Southern China. We obtained data on scrub typhus cases in Guangzhou every month from 2006 to 2014 from the Chinese communicable disease network. Time-series Poisson regression models and distributed lag nonlinear models (DLNM) were used to evaluate the relationship between risk factors and scrub typhus. Wavelet analysis found the incidence of scrub typhus cycled with a period of approximately 8-12 months and long-term trends with a period of approximately 24-36 months. The DLNM model shows that relative humidity, rainfall, DTR, MEI and rodent density were associated with the incidence of scrub typhus. Our findings suggest that the incidence scrub typhus has two main temporal cycles. Determining the reason for this trend and how it can be used for disease control and prevention requires additional research. The transmission of scrub typhus is highly dependent on climate factors and rodent density, both of which should be considered in prevention and control strategies for scrub typhus.
Spatiotemporal Dynamics of Scrub Typhus Transmission in Mainland China, 2006-2014
Hu, Wen-Biao; Haque, Ubydul; Weppelmann, Thomas A.; Wang, Yong; Liu, Yun-Xi; Li, Xin-Lou; Sun, Hai-Long; Sun, Yan-Song; Clements, Archie C. A.; Li, Shen-Long; Zhang, Wen-Yi
2016-01-01
Background Scrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized. Objective This study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease. Method Monthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted. Results During the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation. Conclusions The results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country. PMID:27479297
Spatiotemporal Dynamics of Scrub Typhus Transmission in Mainland China, 2006-2014.
Wu, Yi-Cheng; Qian, Quan; Soares Magalhaes, Ricardo J; Han, Zhi-Hai; Hu, Wen-Biao; Haque, Ubydul; Weppelmann, Thomas A; Wang, Yong; Liu, Yun-Xi; Li, Xin-Lou; Sun, Hai-Long; Sun, Yan-Song; Clements, Archie C A; Li, Shen-Long; Zhang, Wen-Yi
2016-08-01
Scrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized. This study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease. Monthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted. During the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation. The results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country.
Effect of Latitude and Seasonal Variation on Scrub Typhus, South Korea, 2001–2013
Jeung, Ye Sul; Kim, Choon-Mee; Yun, Na Ra; Kim, Seok-Won; Han, Mi Ah; Kim, Dong-Min
2016-01-01
In South Korea, scrub typhus is one of the most common rickettsial diseases. The number of scrub typhus patients has increased in South Korea, a total of 69,210 cases were reported from 2001 to 2013. The seasonality and relation of scrub typhus cases to latitude were analyzed in this article using data obtained from the National Notifiable Diseases Surveillance System website of the Korea Centers for Disease Control and Prevention. The incidence of scrub typhus tended to increase in the later months of the year, especially in October–December. In general, lower latitudes were associated with a later peak incidence. Our results suggest for the first time that the monthly observed incidence tended to increase in the later months of the year as the latitude decreased, and on a yearly basis in Korea. PMID:26503283
Acute Cholecystitis in Patients with Scrub Typhus.
Lee, Hyun; Ji, Misuk; Hwang, Jeong-Hwan; Lee, Ja-Yeon; Lee, Ju-Hyung; Chung, Kyung Min; Lee, Chang-Seop
2015-11-01
Acute cholecystitis is a rare complication of scrub typhus. Although a few such cases have been reported in patients with scrub typhus, the clinical course is not well described. Of 12 patients, acute cholecystitis developed in 66.7% (8/12) of patients older than 60 yr. The scrub typhus group with acute cholecystitis had marginal significant longer hospital stay and higher cost than the group without cholecystitis according to propensity score matching. Scrub typhus should be kept in mind as a rare etiology of acute cholecystitis in endemic areas because the typical signs of scrub typhus such as skin rash and eschar can present after the abdominal pain.
Scrub Typhus Outbreak in a Remote Primary School, Bhutan, 2014.
Tshokey, Tshokey; Graves, Stephen; Tshering, Dorji; Phuntsho, Kelzang; Tshering, Karchung; Stenos, John
2017-08-01
Scrub typhus in Bhutan was first reported in 2009. We investigated an outbreak of scrub typhus in a remote primary school during August-October 2014. Delay in recognition and treatment resulted in 2 deaths from meningoencephalitis. Scrub typhus warrants urgent public health interventions in Bhutan.
Risk factors associated with severe scrub typhus in Shandong, northern China.
Zhang, Luyan; Zhao, Zhongtang; Bi, Zhenwang; Kou, Zengqiang; Zhang, Meng; Yang, Li; Zheng, Li
2014-12-01
The aim of this study was to identify risk factors associated with severe scrub typhus, in order to provide a reference for clinical decision-making. A case-control study was conducted of scrub typhus patients who presented at local hospitals between 2010 and 2013. In total, 46 patients with severe scrub typhus complications (cases) and 194 without severe complications (controls) were included. There were significant differences in the duration of illness before effective antibiotic therapy, lymphadenopathy, rash, blood platelet count, white blood cell (WBC) count, percentage neutrophils, and percentage lymphocytes between the case and control groups. Multivariate analysis demonstrated that the following four factors were significantly associated with the severe complications of scrub typhus: (1) duration of illness before effective antibiotic therapy (odds ratio (OR) 2.287, 95% confidence interval (CI) 1.096-4.770); (2) the presence of a rash (OR 3.694, 95% CI 1.300-10.495); (3) lymphadenopathy (OR 2.438, 95% CI 1.090-5.458); (4) blood platelet count <100×10(9)/l (OR 2.226, 95% CI 1.002-4.946). This study indicates that improved diagnosis and timely treatment are important factors for the prevention of severe scrub typhus. When scrub typhus patients present with a rash, lymphadenopathy, or blood platelet count <100×10(9)/l, clinicians should be alert to the appearance of severe complications. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Acute pancreatitis associated with scrub typhus.
Sv, Padmavathi Devi; M, Aruna; Kumar, Anil Cv; Krishna Reddy, Hari; Bl, Sangeetha; Siva Kumar, V
2017-01-01
Scrub typhus, or tsutsugamushi fever, is a zoonosis of rural Asia and the western Pacific islands. The causative organism, Orientia (formerly Rickettsia) tsutsugamushi, is transmitted to humans by the bite of a larval Leptotrombidium mite (chigger). Scrub typhus may have gastrointestinal presentations, such as acute acalculous cholecystitis, duodenal ulcer perforation, peritonitis and gastric ulceration. Acute pancreatitis with scrub typhus has been reported rarely. We report a patient of scrub typhus complicated by acute pancreatitis and acute kidney injury. © The Author(s) 2016.
Zheng, L; Yang, H-L; Bi, Z-W; Kou, Z-Q; Zhang, L-Y; Zhang, A-H; Yang, L; Zhao, Z-T
2015-08-01
Tai'an, a famous cultural tourist district, is a new endemic foci of scrub typhus in northern China. Frequent reports of travel-acquired cases and absence of effective vaccine indicated a significant health problem of scrub typhus in Tai'an. Thus, descriptive epidemiological methods and spatial-temporal scan statistics were used to describe the epidemic characteristics and detect the significant clusters of the high incidence of scrub typhus at the town level in Tai'an. Results of descriptive epidemiological analysis showed a total of 490 cases were reported in Tai'an with the annual average incidence ranging from 0·48 to 2·27/100 000 during 2006-2013. Females, the elderly and farmers are the high-risk groups. Monthly changes of scrub typhus cases indicated an obvious epidemic period in autumn. Spatial-temporal distribution analysis, showed significant clusters of high incidence mainly located in eastern and northern Tai'an. Our study suggests that more effective, targeted measures for local residents should be implemented in the eastern and northern areas of Tai'an in autumn. Meanwhile, it may prove beneficial for health policy makers to advise travellers to take preventive measures in order to minimize the risk of infection of scrub typhus in Tai'an.
Scrub typhus: Clinical spectrum and outcome.
Venkategowda, Pradeep M; Rao, S Manimala; Mutkule, Dnyaneshwar P; Rao, Mallela V; Taggu, Alai N
2015-04-01
Scrub typhus is one of the differential diagnoses for fever with thrombocytopenia. ARDS associated with Scrub typhus has high morbidity and mortality. To evaluate clinical features, lab values, and outcome in patients with scrub typhus and comparison in patients with or without ARDS. A prospective observational study was conducted on 109 patients with febrile illness and thrombocytopenia during a period of 12 months. All 109 patients were tested with both Immune-chromatography test and Weil felix test. Patients having either Immune-chromatography test/Weil felix test positive have been included and considered as scrub typhus positive whereas negative for both Immune-chromatography and Weil felix test were excluded. Clinical features, lab parameters, and outcome were evaluated in all patients with scrub typhus. Statistical analysis used in this study was T-test. Among 58 patients who were included (After exclusion of 51 patients among total of 109 patients) 34 patients had no ARDS and 24 patients had ARDS. The clinical feature like dyspnoea, cough, low blood pressure (MAP<65 mmHg), IVC collapsibility (by ultrasound) and laboratory parameters like decreased Hemoglobin, Hematocrit, Serum albumin, and increased serum creatinine, serum total bilirubin, SGOT, SGPT, LDH, CPK, and serum lactate were statistically significant (P < 0.0001) in scrub typhus patients group with ARDS. The higher titers of Weil-felix can be correlated with more severe form of disease according to our observation. All 34 Scrub typhus patients without ARDS recovered completely. Among 24 Scrub typhus patients with ARDS, 22 patients recovered, and 2 patients died. Scrub typhus is an important differential diagnosis in a patients having fever with thrombocytopenia. Scrub typhus associated with ARDS has high morbidity and mortality. Early diagnosis and treatment with doxycycline can prevent the occurrence of ARDS.
Severe Fever with Thrombocytopenia Syndrome in Patients Suspected of Having Scrub Typhus.
Wi, Yu Mi; Woo, Hye In; Park, Dahee; Lee, Keun Hwa; Kang, Cheol-In; Chung, Doo Ryeon; Peck, Kyong Ran; Song, Jae-Hoon
2016-11-01
To determine prevalence of severe fever with thrombocytopenia syndrome in South Korea, we examined serum samples from patients with fever and insect bite history in scrub typhus-endemic areas. During the 2013 scrub typhus season, prevalence of this syndrome among patients suspected of having scrub typhus was high (23.0%), suggesting possible co-infection.
Neuropsychiatric Manifestations of Scrub Typhus.
Mahajan, Sanjay K; Mahajan, Sanyam K
2017-01-01
Scrub typhus is caused by Orientia tsutsugamushi characterized by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system. It was thought to have been eradicated from India. Recently it is being reported from many areas of India. The clinical picture and severity of the symptoms varies widely. The neurological manifestations of scrub typhus are not uncommon but are diverse. Meningoencephalitis is classical manifestation of scrub typhus but cerebellitis, cranial nerve palsies, plexopathy, transverse myelitis, neuroleptic malignant syndrome and Guillan-Barré syndrome are other manifestations reported in literature. The availability of literature on the neurological manifestations of scrub typhus is limited to case reports mainly. This article reviews various neurological manifestations of scrub typhus reported in literature.
Neuropsychiatric Manifestations of Scrub Typhus
Mahajan, Sanjay K.; Mahajan, Sanyam K.
2017-01-01
Scrub typhus is caused by Orientia tsutsugamushi characterized by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system. It was thought to have been eradicated from India. Recently it is being reported from many areas of India. The clinical picture and severity of the symptoms varies widely. The neurological manifestations of scrub typhus are not uncommon but are diverse. Meningoencephalitis is classical manifestation of scrub typhus but cerebellitis, cranial nerve palsies, plexopathy, transverse myelitis, neuroleptic malignant syndrome and Guillan-Barré syndrome are other manifestations reported in literature. The availability of literature on the neurological manifestations of scrub typhus is limited to case reports mainly. This article reviews various neurological manifestations of scrub typhus reported in literature. PMID:28694624
Chen, Y Z; Li, F; Xu, H; Huang, L C; Gu, Z G; Sun, Z Y; Yan, G J; Zhu, Y J; Tang, C
2016-02-01
In order to provide better programs on monitoring, early warning and prevention of Scrub Typhus in the coastal beach area, temporal-spatial distribution characteristics of scrub typhus were summarized. Relationships between temporal-spatial clustering of Scrub Typhus, meteorological factors, rodent distribution and the biological characteristics in coastal beach area of Yancheng city, were studied. Reports on network-based Scrub Typhus epidemics and information on population, weather situation through monitoring those stations, from 2005 to 2014 were collected and processed, in the coastal beach area of Yancheng city. Distribution, density of the population concerned and seasonal fluctuation on rodents were monitored in coastal beach area, from April 2011 to December, 2013. METHODS as descriptive statistics, space-time permutation scantistics, autocorrelation and Cross-correlation analysis etc, were used to analyze the temporal-spatial distribution of Scrub Typhus and correlation with rodent distribution, density fluctuation and meteorological indexes. Zero-inflated Pearson (ZIP) regression model was contributed according to the distribution of related data. All methods were calculated under Excel 2003, SPSS 16.0, Mapinfo 11.0, Satscan 9.0 and Stata/SE 10.0 softwares. (1) The incidence of Scrub Typhus was gradually increasing and the highest incidence of the year was seen in 2014, as 5.81/10 million. There was an autumn peak of Scrub typhus, with the highest incidence rate as 12.02/10 million in November. The incidence rate of Scrub typhus appeared high in Binhai, Dafeng and Xiangshui, with the average incidence rates appeared as 3.30/10 million, 3.21/10 million and 2.79/10 million, respectively. There were 12 towns with high incidence rates in the coastal beach area, with incidence rate showed between 4.41/10 and 10.03/10 million. (2) There were three incidence clusters of Scrub typhus seen in 25 towns, between October 2012 and November 2012 in Dongtai, Dafeng, Sheyang areas and 5 towns between October and November, 2014 in Xiangshui area, together with another 6 towns in November of 2006, in Binhai area. (3) Apodemus agrarius appeared the dominant species in the coastal area, with the constituent ratio as 89.19%. The rodent density appeared two peaks in winter and summer in 2011 and 2013. The winter peak was seen in January and the summer peak lasting for 5-8 months. Scrub Typhus was seen 10-11 months in a year and the incidence was increasing, parallel with the peak of the rodent density. The peak incidence of Scrub Typhus showed a temperature/rainfall-related peak. Rodent density, temperature, rainfalls were correlated with the incidence of Scrub Typhus, under the Cross correlation analysis. Rains, Mean minimum temperature of a 3-month lagging were directly correlated but the duration of sunshine and relative humidity were negatively correlated with the incidence of Scrub Typhus, under the Zero-inflated Pearson (ZIP) regression model. Temporal-spatial clustering and factors as media creature and weather condition of Scrub Typhu were discovered, which provided evidence for effective measures on prevention and control of the disease.
Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea.
Kwak, Jaewon; Kim, Soojun; Kim, Gilho; Singh, Vijay P; Hong, Seungjin; Kim, Hung Soo
2015-06-29
Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN) model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered.
Scrub Typhus Incidence Modeling with Meteorological Factors in South Korea
Kwak, Jaewon; Kim, Soojun; Kim, Gilho; Singh, Vijay P.; Hong, Seungjin; Kim, Hung Soo
2015-01-01
Since its recurrence in 1986, scrub typhus has been occurring annually and it is considered as one of the most prevalent diseases in Korea. Scrub typhus is a 3rd grade nationally notifiable disease that has greatly increased in Korea since 2000. The objective of this study is to construct a disease incidence model for prediction and quantification of the incidences of scrub typhus. Using data from 2001 to 2010, the incidence Artificial Neural Network (ANN) model, which considers the time-lag between scrub typhus and minimum temperature, precipitation and average wind speed based on the Granger causality and spectral analysis, is constructed and tested for 2011 to 2012. Results show reliable simulation of scrub typhus incidences with selected predictors, and indicate that the seasonality in meteorological data should be considered. PMID:26132479
Multiple eschars in scrub typhus: a case report.
Koraluru, Munegowda; Nandigam, Manideep; Bairy, Indira; Vidyasagar, Sudha; Varma, Muralidhar
2017-01-01
Eschar in scrub typhus aids in early diagnosis and institution of appropriate therapy; however, the eschar positivity rates vary greatly in endemic regions. Multiple eschars in scrub typhus are a rare presentation. Our patient presented with fever and multiple eschars and was empirically started on doxycycline. Nested polymerase chain reaction from all the four eschars and from EDTA blood were positive for 56-kDa type-specific antigen which is specific for Orientia tsutsugamushi The patient recovered completely after 7 days of antibiotic treatment. He was from an area where scrub typhus was not observed previously. An eschar in an acute febrile patient from the "tsutsugamushi triangle" is a valuable sign in scrub typhus diagnosis. A search for multiple eschars in scrub typhus must be made by clinicians. © The Author(s) 2016.
Successfully Managed Acute Transverse Myelitis Related to Scrub Typhus and Serial Image Findings
Yun, Jae Sung; Song, Ji Soo; Choi, Eun Jung; Hwang, Jeong-Hwan; Lee, Chang-Seop; Park, Eun Hae
2017-01-01
Central nervous system involvement manifesting as meningitis or meningoencephalitis is a known complication of scrub typhus, but very few spinal cord lesions such as acute transverse myelitis (ATM) have been reported in association with this disease. Scrub typhus patients with a spinal lesion present with neurologic symptoms including dysuria, motor, and sensory weakness. Herein, we describe a rare case of ATM associated with scrub typhus. Clinical characteristics, cerebrospinal fluid cytology, Orientia tsutsugamushi serum antibody titer, and serial magnetic resonance imaging scans resulted in a diagnosis of ATM associated with scrub typhus. PMID:28115665
Successfully Managed Acute Transverse Myelitis Related to Scrub Typhus and Serial Image Findings.
Yun, Jae Sung; Song, Ji Soo; Choi, Eun Jung; Hwang, Jeong-Hwan; Lee, Chang-Seop; Park, Eun Hae
2017-03-01
AbstractCentral nervous system involvement manifesting as meningitis or meningoencephalitis is a known complication of scrub typhus, but very few spinal cord lesions such as acute transverse myelitis (ATM) have been reported in association with this disease. Scrub typhus patients with a spinal lesion present with neurologic symptoms including dysuria, motor, and sensory weakness. Herein, we describe a rare case of ATM associated with scrub typhus. Clinical characteristics, cerebrospinal fluid cytology, Orientia tsutsugamushi serum antibody titer, and serial magnetic resonance imaging scans resulted in a diagnosis of ATM associated with scrub typhus.
Lee, Min; Kim, June; Jo, Dae Sun
2017-04-01
Chloramphenicol and tetracycline are not recommended for treating scrub typhus in pediatric patients because of potential side effects, such as aplastic anemia or tooth discoloration. While clarithromycin has recently been used in adults, few reports have been published on its effects in pediatric patients. We report the clinical profiles of pediatric scrub typhus and the effects of clarithromycin on scrub typhus in children. We retrospectively analyzed medical records of 56 children with scrub typhus who were admitted between 2004 and 2013 to Chonbuk National University Hospital, Jeonju, Korea. Cases were divided into 3 groups based on thetreatment drug (chloramphenicol, azithromycin, and clarithromycin). We compared their clinical manifestations and laboratory findings. All patients exhibited fever and rash. Other common clinical manifestations were eschars (66%), lymphadenopathy (48%), upper respiratory symptoms (42%), abdominal pain (32%), and hepatosplenomegaly (14%). Elevated levels of C-reactive protein, erythrocyte sedimentation rates, aspartate transaminase, and alanine transaminase were detected in 95%, 96%, 84%, and 77% of patients, respectively. Additionally, decreased platelet and white blood cell levels were observed in 43% and 36% of patients, respectively. There were no statistical differences between the treatment groups in mean age ( P =0.114) or sex ( P =0.507). However, time to defervescence after the treatments differed significantly, being the shortest in the clarithromycin group ( P =0.019). All patients recovered without complications related to the disease or drugs. Clarithromycin was as effective as chloramphenicol and azithromycin in pediatric scrub typhus patients and may be used as a first-line treatment drug.
Tsai, Pui-Jen; Yeh, Hsi-Chyi
2013-04-29
The Taiwan area comprises the main island of Taiwan and several small islands located off the coast of the Southern China. The eastern two-thirds of Taiwan are characterized by rugged mountains covered with tropical and subtropical vegetation. The western region of Taiwan is characterized by flat or gently rolling plains. Geographically, the Taiwan area is diverse in ecology and environment, although scrub typhus threatens local human populations. In this study, we investigate the effects of seasonal and meteorological factors on the incidence of scrub typhus infection among 10 local climate regions. The correlation between the spatial distribution of scrub typhus and cultivated forests in Taiwan, as well as the relationship between scrub typhus incidence and the population density of farm workers is examined. We applied Pearson's product moment correlation to calculate the correlation between the incidence of scrub typhus and meteorological factors among 10 local climate regions. We used the geographically weighted regression (GWR) method, a type of spatial regression that generates parameters disaggregated by the spatial units of analysis, to detail and map each regression point for the response variables of the standardized incidence ratio (SIR)-district scrub typhus. We also applied the GWR to examine the explanatory variables of types of forest-land use and farm worker density in Taiwan in 2005. In the Taiwan Area, scrub typhus endemic areas are located in the southeastern regions and mountainous townships of Taiwan, as well as the Pescadore, Kinmen, and Matou Islands. Among these islands and low-incidence areas in the central western and southwestern regions of Taiwan, we observed a significant correlation between scrub typhus incidence and surface temperature. No similar significant correlation was found in the endemic areas (e.g., the southeastern region and the mountainous area of Taiwan). Precipitation correlates positively with scrub typhus incidence in 3 local climate regions (i.e., Taiwan's central western and southwestern regions, and the Kinmen Islands). Relative humidity correlates positively with incidence in Southwestern Taiwan and the Kinmen Islands. The number of wet days correlates positively with incidence in Southwestern Taiwan. The duration of sunshine correlates positively with incidence in Central Western Taiwan, as well as the Kinmen and Matou Islands. In addition, the 10 local climatic regions can be classified into the following 3 groups, based on the warm-cold seasonal fluctuations in scrub typhus incidence: (a) Type 1, evident in 5 local climate regions (Taiwan's northern, northwestern, northeastern, and southeastern regions, as well as the mountainous area); (b) Type 2 (Taiwan's central western and southwestern regions, and the Pescadore Islands); and (c) Type 3 (the Kinmen and Matou Islands). In the GWR models, the response variable of the SIR-district scrub typhus has a statistically significantly positive association with 2 explanatory variables (farm worker population density and timber management). In addition, other explanatory variables (recreational forests, natural reserves, and "other purpose" areas) show positive or negative signs for parameter estimates in various locations in Taiwan. Negative signs of parameter estimates occurred only for the explanatory variables of national protectorates, plantations, and clear-cut areas. The results of this study show that scrub typhus in Taiwan can be classified into 3 types. Type 1 exhibits no climatic effect, whereas the incidence of Type 2 correlates positively with higher temperatures during the warm season, and the incidence of Type 3 correlates positively with higher surface temperatures and longer hours of sunshine. The results also show that in the mountainous township areas of Taiwan's central and southern regions, as well as in Southeastern Taiwan, higher SIR values for scrub typhus are associated with the following variables: farm worker population density, timber management, and area type (i.e., recreational forest, natural reserve, or other purpose).
2013-01-01
Background The Taiwan area comprises the main island of Taiwan and several small islands located off the coast of the Southern China. The eastern two-thirds of Taiwan are characterized by rugged mountains covered with tropical and subtropical vegetation. The western region of Taiwan is characterized by flat or gently rolling plains. Geographically, the Taiwan area is diverse in ecology and environment, although scrub typhus threatens local human populations. In this study, we investigate the effects of seasonal and meteorological factors on the incidence of scrub typhus infection among 10 local climate regions. The correlation between the spatial distribution of scrub typhus and cultivated forests in Taiwan, as well as the relationship between scrub typhus incidence and the population density of farm workers is examined. Methods We applied Pearson’s product moment correlation to calculate the correlation between the incidence of scrub typhus and meteorological factors among 10 local climate regions. We used the geographically weighted regression (GWR) method, a type of spatial regression that generates parameters disaggregated by the spatial units of analysis, to detail and map each regression point for the response variables of the standardized incidence ratio (SIR)-district scrub typhus. We also applied the GWR to examine the explanatory variables of types of forest-land use and farm worker density in Taiwan in 2005. Results In the Taiwan Area, scrub typhus endemic areas are located in the southeastern regions and mountainous townships of Taiwan, as well as the Pescadore, Kinmen, and Matou Islands. Among these islands and low-incidence areas in the central western and southwestern regions of Taiwan, we observed a significant correlation between scrub typhus incidence and surface temperature. No similar significant correlation was found in the endemic areas (e.g., the southeastern region and the mountainous area of Taiwan). Precipitation correlates positively with scrub typhus incidence in 3 local climate regions (i.e., Taiwan’s central western and southwestern regions, and the Kinmen Islands). Relative humidity correlates positively with incidence in Southwestern Taiwan and the Kinmen Islands. The number of wet days correlates positively with incidence in Southwestern Taiwan. The duration of sunshine correlates positively with incidence in Central Western Taiwan, as well as the Kinmen and Matou Islands. In addition, the 10 local climatic regions can be classified into the following 3 groups, based on the warm-cold seasonal fluctuations in scrub typhus incidence: (a) Type 1, evident in 5 local climate regions (Taiwan’s northern, northwestern, northeastern, and southeastern regions, as well as the mountainous area); (b) Type 2 (Taiwan’s central western and southwestern regions, and the Pescadore Islands); and (c) Type 3 (the Kinmen and Matou Islands). In the GWR models, the response variable of the SIR-district scrub typhus has a statistically significantly positive association with 2 explanatory variables (farm worker population density and timber management). In addition, other explanatory variables (recreational forests, natural reserves, and “other purpose” areas) show positive or negative signs for parameter estimates in various locations in Taiwan. Negative signs of parameter estimates occurred only for the explanatory variables of national protectorates, plantations, and clear-cut areas. Conclusion The results of this study show that scrub typhus in Taiwan can be classified into 3 types. Type 1 exhibits no climatic effect, whereas the incidence of Type 2 correlates positively with higher temperatures during the warm season, and the incidence of Type 3 correlates positively with higher surface temperatures and longer hours of sunshine. The results also show that in the mountainous township areas of Taiwan’s central and southern regions, as well as in Southeastern Taiwan, higher SIR values for scrub typhus are associated with the following variables: farm worker population density, timber management, and area type (i.e., recreational forest, natural reserve, or other purpose). PMID:23627966
Thiga, Jacqueline W; Mutai, Beth K; Eyako, Wurapa K; Ng'ang'a, Zipporah; Jiang, Ju; Richards, Allen L; Waitumbi, John N
2015-04-01
Serum samples from patients in Kenya with febrile illnesses were screened for antibodies against bacteria that cause spotted fever, typhus, and scrub typhus. Seroprevalence was 10% for spotted fever group, <1% for typhus group, and 5% for scrub typhus group. Results should help clinicians expand their list of differential diagnoses for undifferentiated fevers.
A Spatiotemporal Database to Track Human Scrub Typhus Using the VectorMap Application
Kelly, Daryl J.; Foley, Desmond H.; Richards, Allen L.
2015-01-01
Scrub typhus is a potentially fatal mite-borne febrile illness, primarily of the Asia-Pacific Rim. With an endemic area greater than 13 million km2 and millions of people at risk, scrub typhus remains an underreported, often misdiagnosed febrile illness. A comprehensive, updatable map of the true distribution of cases has been lacking, and therefore the true risk of disease within the very large endemic area remains unknown. The purpose of this study was to establish a database and map to track human scrub typhus. An online search using PubMed and the United States Armed Forces Pest Management Board Literature Retrieval System was performed to identify articles describing human scrub typhus cases both within and outside the traditionally accepted endemic regions. Using World Health Organization guidelines, stringent criteria were used to establish diagnoses for inclusion in the database. The preliminary screening of 181 scrub typhus publications yielded 145 publications that met the case criterion, 267 case records, and 13 serosurvey records that could be georeferenced, describing 13,739 probable or confirmed human cases in 28 countries. A map service has been established within VectorMap (www.vectormap.org) to explore the role that relative location of vectors, hosts, and the pathogen play in the transmission of mite-borne scrub typhus. The online display of scrub typhus cases in VectorMap illustrates their presence and provides an up-to-date geographic distribution of proven scrub typhus cases. PMID:26678263
A Spatiotemporal Database to Track Human Scrub Typhus Using the VectorMap Application.
Kelly, Daryl J; Foley, Desmond H; Richards, Allen L
2015-12-01
Scrub typhus is a potentially fatal mite-borne febrile illness, primarily of the Asia-Pacific Rim. With an endemic area greater than 13 million km2 and millions of people at risk, scrub typhus remains an underreported, often misdiagnosed febrile illness. A comprehensive, updatable map of the true distribution of cases has been lacking, and therefore the true risk of disease within the very large endemic area remains unknown. The purpose of this study was to establish a database and map to track human scrub typhus. An online search using PubMed and the United States Armed Forces Pest Management Board Literature Retrieval System was performed to identify articles describing human scrub typhus cases both within and outside the traditionally accepted endemic regions. Using World Health Organization guidelines, stringent criteria were used to establish diagnoses for inclusion in the database. The preliminary screening of 181 scrub typhus publications yielded 145 publications that met the case criterion, 267 case records, and 13 serosurvey records that could be georeferenced, describing 13,739 probable or confirmed human cases in 28 countries. A map service has been established within VectorMap (www.vectormap.org) to explore the role that relative location of vectors, hosts, and the pathogen play in the transmission of mite-borne scrub typhus. The online display of scrub typhus cases in VectorMap illustrates their presence and provides an up-to-date geographic distribution of proven scrub typhus cases.
Status epilepticus in scrub typhus.
Kalita, Jayantee; Mani, Vinita E; Bhoi, Sanjeev K; Misra, Usha K
2016-07-01
Scrub typhus is an emerging infection, and there is little information about status epilepticus (SE) in scrub typhus. We report the clinical spectrum and outcome of SE in scrub typhus. In a 3-year prospective hospital-based observational study, all scrub typhus patients with SE were included. Scrub typhus was diagnosed by immunochromatography assay. SE was defined if convulsions lasted longer than 5 min. The patients' demographic, clinical, computed tomography (CT), magnetic resonance imaging (MRI), and electroencephalography (EEG) findings were noted. Response to antiepileptic drugs (AEDs) and outcome at 1 month and 1 year were recorded. Between 2012 and 2014, there were 66 patients with scrub typhus admitted with central nervous system (CNS) involvement, 10 (15.2%) of whom had SE (generalized convulsions in 5, secondary generalized in one). The median age of the patients was 34 (range 18-71) years and seven were female. The duration of SE ranged between 10 min and 48 h. SE responded to one AED in five patients, two AEDs in three patients, and more than two AEDs in two patients. Cranial MRI findings were normal. All patients recovered completely with doxycycline by 1 month and AED was withdrawn by 8 months in all. Although 15% patients with scrub typhus may have SE, they have good outcome. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.
A comparative study of hepatitis caused by scrub typhus and viral hepatitis A in South Korea.
Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Byeon, Yu Mi; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo; Han, Mi Ah
2011-11-01
We compared clinical features and laboratory findings of 104 patients with hepatitis A and 197 patients with scrub typhus. Nausea, vomiting, abdominal pain, hepatomegaly, and jaundice were common in patient with hepatitis A, and fever and headache were significantly more common in patients with scrub typhus. At presentation, an alanine aminotransferase (ALT) level ≥ 500 U/L was observed in 1% of scrub typhus patients and in 87.5% of hepatitis A patients (P < 0.001). A bilirubin level ≥ 1.3 mg/dL was observed in 16.8% of scrub typhus patients and 90.4% of hepatitis A patients. The ALT:lactate dehydrogenase ratio was ≤ 5 in 97.4% of the patients with scrub typhus and > 5 in 95.2% of those with hepatitis A (P < 0.001). Fever, headache, rash, and eschar are findings that indicate scrub typhus. An ALT level ≥ 500 U/L (adjusted odds ratio = 0.011) a bilirubin level ≥ 1.3 (adjusted odds ratio = 0.024), an ALT:lactate dehydrogenase ratio > 5, and hepatomegaly are indications of viral hepatitis A.
A Comparative Study of Hepatitis Caused by Scrub Typhus and Viral Hepatitis A in South Korea
Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Byeon, Yu Mi; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo; Han, Mi Ah
2011-01-01
We compared clinical features and laboratory findings of 104 patients with hepatitis A and 197 patients with scrub typhus. Nausea, vomiting, abdominal pain, hepatomegaly, and jaundice were common in patient with hepatitis A, and fever and headache were significantly more common in patients with scrub typhus. At presentation, an alanine aminotransferase (ALT) level ≥ 500 U/L was observed in 1% of scrub typhus patients and in 87.5% of hepatitis A patients (P < 0.001). A bilirubin level ≥ 1.3 mg/dL was observed in 16.8% of scrub typhus patients and 90.4% of hepatitis A patients. The ALT:lactate dehydrogenase ratio was ≤ 5 in 97.4% of the patients with scrub typhus and > 5 in 95.2% of those with hepatitis A (P < 0.001). Fever, headache, rash, and eschar are findings that indicate scrub typhus. An ALT level ≥ 500 U/L (adjusted odds ratio = 0.011) a bilirubin level ≥ 1.3 (adjusted odds ratio = 0.024), an ALT:lactate dehydrogenase ratio > 5, and hepatomegaly are indications of viral hepatitis A. PMID:22049041
Wardrop, Nicola A; Kuo, Chi-Chien; Wang, Hsi-Chieh; Clements, Archie C A; Lee, Pei-Fen; Atkinson, Peter M
2013-11-01
Scrub typhus is transmitted by the larval stage of trombiculid mites. Environmental factors, including land cover and land use, are known to influence breeding and survival of trombiculid mites and, thus, also the spatial heterogeneity of scrub typhus risk. Here, a spatially autoregressive modelling framework was applied to scrub typhus incidence data from Taiwan, covering the period 2003 to 2011, to provide increased understanding of the spatial pattern of scrub typhus risk and the environmental and socioeconomic factors contributing to this pattern. A clear spatial pattern in scrub typhus incidence was observed within Taiwan, and incidence was found to be significantly correlated with several land cover classes, temperature, elevation, normalized difference vegetation index, rainfall, population density, average income and the proportion of the population that work in agriculture. The final multivariate regression model included statistically significant correlations between scrub typhus incidence and average income (negatively correlated), the proportion of land that contained mosaics of cropland and vegetation (positively correlated) and elevation (positively correlated). These results highlight the importance of land cover on scrub typhus incidence: mosaics of cropland and vegetation represent a transitional land cover type which can provide favourable habitats for rodents and, therefore, trombiculid mites. In Taiwan, these transitional land cover areas tend to occur in less populated and mountainous areas, following the frontier establishment and subsequent partial abandonment of agricultural cultivation, due to demographic and socioeconomic changes. Future land use policy decision-making should ensure that potential public health outcomes, such as modified risk of scrub typhus, are considered.
Yang, Li-Ping; Liang, Si-Yuan; Wang, Xian-Jun; Li, Xiu-Jun; Wu, Yan-Ling; Ma, Wei
2015-01-01
Background Laiwu District is recognized as a hyper-endemic region for scrub typhus in Shandong Province, but the seriousness of this problem has been neglected in public health circles. Methodology/Principal Findings A disability-adjusted life years (DALYs) approach was adopted to measure the burden of scrub typhus in Laiwu, China during the period 2006 to 2012. A multiple seasonal autoregressive integrated moving average model (SARIMA) was used to identify the most suitable forecasting model for scrub typhus in Laiwu. Results showed that the disease burden of scrub typhus is increasing yearly in Laiwu, and which is higher in females than males. For both females and males, DALY rates were highest for the 60–69 age group. Of all the SARIMA models tested, the SARIMA(2,1,0)(0,1,0)12 model was the best fit for scrub typhus cases in Laiwu. Human infections occurred mainly in autumn with peaks in October. Conclusions/Significance Females, especially those of 60 to 69 years of age, were at highest risk of developing scrub typhus in Laiwu, China. The SARIMA (2,1,0)(0,1,0)12 model was the best fit forecasting model for scrub typhus in Laiwu, China. These data are useful for developing public health education and intervention programs to reduce disease. PMID:25569248
Acute transverse myelitis following scrub typhus: A case report and review of the literature.
Ryu, Hyun-Seung; Moon, Bong Ju; Park, Jae-Young; Kim, Sang-Deok; Seo, Seung-Kwon; Lee, Jung-Kil
2018-01-19
Context Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi. The disease can usually involve the lungs, heart, liver, spleen and brain through hematogenous dissemination. However, very rarely, acute transverse myelitis in the spinal cord develops from scrub typhus. We present a case of acute transverse myelitis following scrub typhus with a review of the literature. Findings A 66-year-old male visited a hospital for general myalgia, mild headache, and fever in October. He was noted to have thick, black papule skin on his abdomen, which was highly suggestive of scrub typhus. To confirm the diagnosis, O. tsutsugamushi antibody titers were examined and detected highly in serum by an indirect fluorescence antibody assay. Doxycycline, the standard treatment for scrub typhus, was administered. However, after seven days of treatment, he rapidly developed weakness in the right leg, paresthesia in both lower limbs, and voiding difficulty. Spinal magnetic resonance imaging (MRI) revealed lesions with high signal intensity involving the spinal cord at the thoracolumbar junction. Paraparesis gradually improved following steroid pulse therapy for five days. At one-year follow-up, he could walk without cane. Conclusions Orientia tsutsugamushi causes scrub typhus, which can affect not only the brain, but also the spinal cord. Although acute transverse myelitis develops rarely from scrub typhus, this should be considered as differential diagnosis in patients of fever with neurological deficit in endemic areas.
Charoenphak, Sirima; Rattanawong, Pattara; Sungkanuparph, Somnuek
2017-01-01
Scrub typhus rarely presents with acute cholecystitis. We present 2 cases of scrub typhus with cholecystitis. The first patient is a 62 year old female who presented to the hospital with fever and body aches for 1 week and right upper quadrant abdominal pain for 3 days. She gave a history of an insect bite 2 weeks previously. She was diagnosed as having acute cholecystitis and underwent cholecystectomy. She continued with fever post-operatively and physical examination revealed an eschar. She had an immunofluorescence assay (IFA) performed that revealed a high IgM titer for Orientia tsutsugamushi. She was diagnosed as having scrub typhus, treated with doxycycline and she recovered completely. The second patient also presented to the hospital with a 1 week history of fever and upper quadrant abdominal pain. She was diagnosed with having cholecystitis. Her symptoms did not improve with intravenous antibiotics and further investigation revealed elevated titers for O. tsutsugamushi and Leptospira interrogans. She was diagnosed as having a co-infection of scrub typhus and leptospirosis and treated with doxycycline. She recovered completely. Patients from scrub typhus endemic regions who present with acute cholecystitis but do not respond to traditional treatment should be tested for scrub typhus and leptospirosis and should have a careful admission physical examination looking for eschar formation, since scrub typhus may present with acute cholecystitis.
Valappil, Ashraf V; Thiruvoth, Sohanlal; Peedikayil, Jabir M; Raghunath, Praveenkumar; Thekkedath, Manojan
2017-12-01
The involvement of the central nervous system in the form of meningitis or meningoencephalitis is common in scrub typhus and is an important differential diagnosis of other lymphocytic meningitis like tuberculous meningitis (TBM). The aim of this study was to identify the clinical and laboratory parameters that may be helpful in differentiating scrub typhus meningitis from TBM. We compared of the clinical and laboratory features of 57 patients admitted with scrub typhus meningitis or TBM during a 3-year period. Patients who had abnormal cerebrospinal fluid (CSF) and positive scrub typhus enzyme-linked immunosorbent assay serology (n=28) were included in the scrub typhus meningitis group, while the TBM group included those who satisfied the consensus diagnostic criteria of TBM (n=29). Compared with the TBM group, the mean duration of symptoms was less in patients with scrub typhus meningitis, who also had a lower magnitude of neurological deficits, such as altered mental status and cranial nerve and motor deficits. Patients with scrub typhus meningitis had a lower CSF white blood-cell count (WBC) than the TBM group (130.8±213 195±175 cells/mm 3 , P=0.002), lower CSF protein elevation (125±120 vs. 195.2±108.2mg/dl, P=0.002), and higher CSF sugar (70.1±32.4 vs. 48.7±23.4mg/dl, P=0.006). Features predictive of the diagnosis of scrub typhus meningitis included the absence of neurological impairment at presentation, blood serum glutamic-oxaloacetic transaminase>40 international units (IU)/L, serum glutamic-pyruvic transaminase>60 IU/L, total blood leukocyte count>10,000/mm 3 , CSF protein<100mg/dl, CSF sugar>50mg/dl, CSF WBC<100 cells/mm 3 . All patients with scrub typhus meningitis recovered completely following doxycycline therapy CONCLUSIONS: This study suggests that, clinical features, including duration of fever, neurological deficits at presentation and laboratory parameters such as CSF pleocytosis,CSF protein elevation, CSF sugar levels and liver enzyme values are helpful in differentiating scrub typhus meningitis from tuberculous meningits. These features with scrub IgM serology may be helpful in identifying patients with scrub meningitis and in avoiding prolonged empirical antituberculous therapy in cases of lymphocytic meningitis. Copyright © 2017 Elsevier B.V. All rights reserved.
Estimating the burden of scrub typhus: A systematic review.
Bonell, Ana; Lubell, Yoel; Newton, Paul N; Crump, John A; Paris, Daniel H
2017-09-01
Scrub typhus is a vector-borne zoonotic disease that can be life-threatening. There are no licensed vaccines, or vector control efforts in place. Despite increasing awareness in endemic regions, the public health burden and global distribution of scrub typhus remains poorly known. We systematically reviewed all literature from public health records, fever studies and reports available on the Ovid MEDLINE, Embase Classic + Embase and EconLit databases, to estimate the burden of scrub typhus since the year 2000. In prospective fever studies from Asia, scrub typhus is a leading cause of treatable non-malarial febrile illness. Sero-epidemiological data also suggest that Orientia tsutsugamushi infection is common across Asia, with seroprevalence ranging from 9.3%-27.9% (median 22.2% IQR 18.6-25.7). A substantial apparent rise in minimum disease incidence (median 4.6/100,000/10 years, highest in China with 11.2/100,000/10 years) was reported through passive national surveillance systems in South Korea, Japan, China, and Thailand. Case fatality risks from areas of reduced drug-susceptibility are reported at 12.2% and 13.6% for South India and northern Thailand, respectively. Mortality reports vary widely around a median mortality of 6.0% for untreated and 1.4% for treated scrub typhus. Limited evidence suggests high mortality in complicated scrub typhus with CNS involvement (13.6% mortality), multi-organ dysfunction (24.1%) and high pregnancy miscarriage rates with poor neonatal outcomes. Scrub typhus appears to be a truly neglected tropical disease mainly affecting rural populations, but increasingly also metropolitan areas. Rising minimum incidence rates have been reported over the past 8-10 years from countries with an established surveillance system. A wider distribution of scrub typhus beyond Asia is likely, based on reports from South America and Africa. Unfortunately, the quality and quantity of the available data on scrub typhus epidemiology is currently too limited for any economical, mathematical modeling or mapping approaches.
Estimating the burden of scrub typhus: A systematic review
Bonell, Ana; Lubell, Yoel; Newton, Paul N.; Crump, John A.
2017-01-01
Background Scrub typhus is a vector-borne zoonotic disease that can be life-threatening. There are no licensed vaccines, or vector control efforts in place. Despite increasing awareness in endemic regions, the public health burden and global distribution of scrub typhus remains poorly known. Methods We systematically reviewed all literature from public health records, fever studies and reports available on the Ovid MEDLINE, Embase Classic + Embase and EconLit databases, to estimate the burden of scrub typhus since the year 2000. Findings In prospective fever studies from Asia, scrub typhus is a leading cause of treatable non-malarial febrile illness. Sero-epidemiological data also suggest that Orientia tsutsugamushi infection is common across Asia, with seroprevalence ranging from 9.3%–27.9% (median 22.2% IQR 18.6–25.7). A substantial apparent rise in minimum disease incidence (median 4.6/100,000/10 years, highest in China with 11.2/100,000/10 years) was reported through passive national surveillance systems in South Korea, Japan, China, and Thailand. Case fatality risks from areas of reduced drug-susceptibility are reported at 12.2% and 13.6% for South India and northern Thailand, respectively. Mortality reports vary widely around a median mortality of 6.0% for untreated and 1.4% for treated scrub typhus. Limited evidence suggests high mortality in complicated scrub typhus with CNS involvement (13.6% mortality), multi-organ dysfunction (24.1%) and high pregnancy miscarriage rates with poor neonatal outcomes. Interpretation Scrub typhus appears to be a truly neglected tropical disease mainly affecting rural populations, but increasingly also metropolitan areas. Rising minimum incidence rates have been reported over the past 8–10 years from countries with an established surveillance system. A wider distribution of scrub typhus beyond Asia is likely, based on reports from South America and Africa. Unfortunately, the quality and quantity of the available data on scrub typhus epidemiology is currently too limited for any economical, mathematical modeling or mapping approaches. PMID:28945755
Clinical Profile of Scrub Typhus in Pregnancy in Sub-Himalayan Region.
Kumar, Ritesh; Thakur, Surinder; Bhawani, Rajesh; Kanga, Anil; Ranjan, Asha
2016-10-01
Scrub typhus is rare in pregnancy, but it has now become an important cause of febrile illness in pregnancy in sub-Himalayan region of India. Only a few case reports have been published so far, and they show adverse maternal and fetal outcomes. No consensus has been reached till now regarding treatment. All the pregnant patients irrespective of period of gestation admitted with febrile illness with positive IgM ELISA for scrub typhus with or without eschar were included. The clinical profile was observed using a detailed history of symptoms, travel, recreation, agricultural activities, treatment record prior to admission, and a detailed examination, and the treatment outcome was noted. Fever workup including cultures, CXR, CSF analysis, serology for scrub was done. IgM scrub typhus was done by kit method manufactured by InBios Intertational, Inc. We observed in total 14 pregnant patients out of which eight were in the the second trimester and six were in the third trimester. The clinical features of the disease observed for pregnant females were the same as for nonpregnant females. There was no difference in the severity of scrub typhus between pregnant and nonpregnant women. No mortality was found in these patients. On follow-up, they had normal peripartum and postpartum periods. All were treated with azithromycin 500 mg once a day for 5 days. Although rare, scrub typhus should be considered in differential diagnosis of fever in pregnant patients especially in scrub season. Azithromycin should be the drug of choice in pregnancy as it has no adverse effect on fetus and pregnancy outcome.
Kang, Seung-Ji; Jin, Hye-Mi; Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook
2017-07-01
Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients.
Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung
2017-01-01
Background Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. Methodology/Principal findings This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. Conclusions This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients. PMID:28750012
Rapid Increase in Scrub Typhus Incidence in Mainland China, 2006-2014.
Wu, Yi-Cheng; Qian, Quan; Magalhaes, Ricardo J Soares; Han, Zhi-Hai; Haque, Ubydul; Weppelmann, Thomas A; Hu, Wen-Biao; Liu, Yun-Xi; Sun, Yan-Song; Zhang, Wen-Yi; Li, Shen-Long
2016-03-01
Scrub typhus is a vector-borne disease, which has recently reemerged in China. In this study, we describe the distribution and incidence of scrub typhus cases in China from 2006 to 2014 and quantify differences in scrub typhus cases with respect to sex, age, and occupation. The results of our study indicate that the annual incidence of scrub typhus has increased during the study period. The number of cases peaked in 2014, which was 12.8 times greater than the number of cases reported in 2006. Most (77.97%) of the cases were reported in five provinces (Guangdong, Yunnan, Anhui, Fujian, and Shandong). Our study also demonstrates that the incidence rate of scrub typhus was significantly higher in females compared to males (P < 0.001) and was highest in the 60-69 year age group, and that farmers had a higher incidence rate than nonfarmers (P < 0.001). Different seasonal trends were identified in the number of reported cases between the northern and southern provinces of China. These findings not only demonstrate that China has experienced a large increase in scrub typhus incidence, but also document an expansion in the geographic distribution throughout the country. © The American Society of Tropical Medicine and Hygiene.
Scrub typhus as a possible aetiology of Guillain-Barré syndrome: two cases.
Lee, M-S; Lee, J-H; Lee, H-S; Chang, H; Kim, Y-S; Cho, K-H; Ahn, S-H; Song, J-H; Yoo, M; Han, J-K; Park, H-Y
2009-09-01
Neurological complications of scrub typhus are reported to be rare. Peripheral nervous system involvement has been reported in only one case. We present two cases of Guillan-Barré syndrome (GBS) associated with scrub typhus. In both cases, the findings of an elevated indirect immunofluorescent antibody titer for Orientia tsutsugamushi and nerve conduction study showing sensory-motor polyneuropathy, have led us to believe that scrub typhus could be one of the antecedent illnesses associated with GBS.
Activation of the coagulation cascade in patients with scrub typhus.
Lee, Hee-Jeong; Park, Chi-Young; Park, Sang-Gon; Yoon, Na-Ra; Kim, Dong-Min; Chung, Choon-Hae
2017-09-01
This retrospective study aimed to evaluate the levels of coagulation factors and presence of disseminated intravascular coagulation (DIC) in patients with scrub typhus. We included patients confirmed to have scrub typhus at the Chosun University Hospital between September 2004 and December 2009. The DIC scores were evaluated in 365 patients and 36 healthy controls. The median concentrations of fibrinogen, d-dimer, and fibrin/fibrinogen degradation products (FDP) were compared between patients and healthy controls (p<0.001 for all tests). Patients with scrub typhus had longer prothrombin time and lower platelet counts than the controls. Major bleeding was observed in 18/365 patients with scrub typhus. Fifty-one (14.0%) patients presented with severe complications of scrub typhus. Overt DIC and thrombocytopenia (<100,000 platelets/mm 3 ) were observed more frequently in patients with bleeding and severe illness. Furthermore, median platelet counts were low in both groups. Approximately 2.7% (n=10) and 16.4% (n=60) patients with scrub typhus had overt DIC, as defined by the International Society on Thrombosis and Hemostasis DIC score (DIC1) and the DIC-scoring template with a fibrinogen/C-reactive protein-ratio (DIC2), respectively. Three (16.7%) and 10 (55.6%) patients with bleeding had overt DIC, as defined by the DIC1 and DIC2, respectively. Seven (13.7%) and 26 (51%) patients with severe illness had overt DIC, as defined by DIC1 and DIC2, respectively. In conclusion, activation of the coagulation system is an important feature of scrub typhus and is correlated with severe disease, including bleeding. This is the first study to report a relationship between DIC and scrub typhus. Copyright © 2017 Elsevier Inc. All rights reserved.
Hamaguchi, Sugihiro; Cuong, Ngo Chi; Tra, Doan Thu; Doan, Yen Hai; Shimizu, Kenta; Tuan, Nguyen Quang; Yoshida, Lay-Myint; Mai, Le Quynh; Duc-Anh, Dang; Ando, Shuji; Arikawa, Jiro; Parry, Christopher M.; Ariyoshi, Koya; Thuy, Pham Thanh
2015-01-01
A descriptive study on rickettsiosis was conducted at the largest referral hospital in Hanoi, Vietnam, to identify epidemiological and clinical characteristics of specific rickettsiosis. Between March 2001 and February 2003, we enrolled 579 patients with acute undifferentiated fever (AUF), excluding patients with malaria, dengue fever, and typhoid fever, and serologically tested for Orientia tsutsugamushi and Rickettsia typhi. Of the patients, 237 (40.9%) and 193 (33.3%) had scrub and murine typhus, respectively, and 149 (25.7%) had neither of them (non–scrub and murine typhus [non-ST/MT]). The proportion of murine typhus was highest among patients living in Hanoi whereas that of scrub typhus was highest in national or regional border areas. The presence of an eschar, dyspnea, hypotension, and lymphadenopathy was significantly associated with a diagnosis of scrub typhus (OR = 46.56, 10.90, 9.01, and 7.92, respectively). Patients with murine typhus were less likely to have these findings but more likely to have myalgia, rash, and relative bradycardia (OR = 1.60, 1.56, and 1.45, respectively). Scrub typhus and murine typhus were shown to be common causes of AUF in northern Vietnam although the occurrence of spotted fever group rickettsiae was not determined. Clinical and epidemiological information may help local clinicians make clinical diagnosis of specific rickettsioses in a resource-limited setting. PMID:25778504
Paris, Daniel H; Stephan, Femke; Bulder, Ingrid; Wouters, Diana; van der Poll, Tom; Newton, Paul N; Day, Nicholas P J; Zeerleder, Sacha
2015-01-01
Cell-mediated immunity is essential in protection against rickettsial illnesses, but the role of neutrophils in these intracellular vasculotropic infections remains unclear. This study analyzed the plasma levels of nucleosomes, FSAP-activation (nucleosome-releasing factor), and neutrophil activation, as evidenced by neutrophil-elastase (ELA) complexes, in sympatric Lao patients with scrub typhus and murine typhus. In acute scrub typhus elevated nucleosome levels correlated with lower GCS scores, raised respiratory rate, jaundice and impaired liver function, whereas neutrophil activation correlated with fibrinolysis and high IL-8 plasma levels, a recently identified predictor of severe disease and mortality. Nucleosome and ELA complex levels were associated with a 4.8-fold and 4-fold increased risk of developing severe scrub typhus, beyond cut off values of 1,040 U/ml for nucleosomes and 275 U/ml for ELA complexes respectively. In murine typhus, nucleosome levels associated with pro-inflammatory cytokines and the duration of illness, while ELA complexes correlated strongly with inflammation markers, jaundice and increased respiratory rates. This study found strong correlations between circulating nucleosomes and neutrophil activation in patients with scrub typhus, but not murine typhus, providing indirect evidence that nucleosomes could originate from neutrophil extracellular trap (NET) degradation. High circulating plasma nucleosomes and ELA complexes represent independent risk factors for developing severe complications in scrub typhus. As nucleosomes and histones exposed on NETs are highly cytotoxic to endothelial cells and are strongly pro-coagulant, neutrophil-derived nucleosomes could contribute to vascular damage, the pro-coagulant state and exacerbation of disease in scrub typhus, thus indicating a detrimental role of neutrophil activation. The data suggest that increased neutrophil activation relates to disease progression and severe complications, and increased plasma levels of nucleosomes and ELA complexes represent independent risk factors for developing severe scrub typhus.
Paris, Daniel H.; Stephan, Femke; Bulder, Ingrid; Wouters, Diana; van der Poll, Tom; Newton, Paul N.; Day, Nicholas P. J.; Zeerleder, Sacha
2015-01-01
Cell-mediated immunity is essential in protection against rickettsial illnesses, but the role of neutrophils in these intracellular vasculotropic infections remains unclear. This study analyzed the plasma levels of nucleosomes, FSAP-activation (nucleosome-releasing factor), and neutrophil activation, as evidenced by neutrophil-elastase (ELA) complexes, in sympatric Lao patients with scrub typhus and murine typhus. In acute scrub typhus elevated nucleosome levels correlated with lower GCS scores, raised respiratory rate, jaundice and impaired liver function, whereas neutrophil activation correlated with fibrinolysis and high IL-8 plasma levels, a recently identified predictor of severe disease and mortality. Nucleosome and ELA complex levels were associated with a 4.8-fold and 4-fold increased risk of developing severe scrub typhus, beyond cut off values of 1,040 U/ml for nucleosomes and 275 U/ml for ELA complexes respectively. In murine typhus, nucleosome levels associated with pro-inflammatory cytokines and the duration of illness, while ELA complexes correlated strongly with inflammation markers, jaundice and increased respiratory rates. This study found strong correlations between circulating nucleosomes and neutrophil activation in patients with scrub typhus, but not murine typhus, providing indirect evidence that nucleosomes could originate from neutrophil extracellular trap (NET) degradation. High circulating plasma nucleosomes and ELA complexes represent independent risk factors for developing severe complications in scrub typhus. As nucleosomes and histones exposed on NETs are highly cytotoxic to endothelial cells and are strongly pro-coagulant, neutrophil-derived nucleosomes could contribute to vascular damage, the pro-coagulant state and exacerbation of disease in scrub typhus, thus indicating a detrimental role of neutrophil activation. The data suggest that increased neutrophil activation relates to disease progression and severe complications, and increased plasma levels of nucleosomes and ELA complexes represent independent risk factors for developing severe scrub typhus. PMID:26317419
Predictors of Severity in Pediatric Scrub Typhus.
Narayanasamy, Dinesh Kumar; Arun Babu, Thirunavukkarasu; Vijayadevagaran, Vijayasankar; Kittu, Devi; Ananthakrishnan, Shanthi
2018-01-24
To identify the factors that can predict the severity of scrub typhus in children. This prospective study was conducted at a tertiary care teaching hospital between November 2014 to October 2016. All children <12y of age admitted with fever for more than 7d and positive IgM ELISA for scrub typhus were included in the study. These children were followed during the hospital course and their laboratory results, response to treatment and complications were documented. Cases of 'severe scrub typhus' were identified based on criteria from published adult and pediatric studies. Out of 930 children with fever for more than 7d, IgM ELISA for scrub typhus was positive in 230 children. Ninety one (40.6%) cases fulfilled the criteria of 'severe scrub typhus' in children. Out of 45 factors, 27 potential factors were studied. The multivariate analysis identified 5 factors, breathlessness (OR: 6.85, 95%CI: 2.69 to 9.87), altered sensorium (OR: 11.48, 95% CI 3.43 to 10.19), leucocytosis (OR: 3.38, 95% CI 1.12 to 10.16), hypoalbuminemia (OR: 10.78, 95% CI 2.66 to 48.76), and hyponatremia (OR: 10.08, 95% CI 2.11 to 23.42) to be significantly associated with the 'severe scrub typhus' cases. Breathlessness, altered sensorium, leucocytosis, hypoalbuminemia, and hyponatremia predict severity in childhood scrub typhus. Presence of these factors should alert the treating physician regarding the need for intensive monitoring, treatment or referral.
Rapsang, Amy G; Bhattacharyya, Prithwis
2013-01-01
Scrub typhus is an acute febrile illness caused by orientia tsutsugamushi, transmitted to humans by the bite of the larva of trombiculid mites. It causes a disseminated vasculitic and perivascular inflammatory lesions resulting in significant vascular leakage and end-organ injury. It affects people of all ages and even though scrub typhus in pregnancy is uncommon, it is associated with increased foetal loss, preterm delivery, and small for gestational age infants. After an incubation period of 6-21 days, onset is characterized by fever, headache, myalgia, cough, and gastrointestinal symptoms. A primary papular lesion which later crusts to form a flat black eschar, may be present. If untreated, serious complications may occur involving various organs. Laboratory studies usually reveal leukopenia, thrombocytopenia, deranged hepatic and renal function, proteinuria and reticulonodular infiltrate. Owing to the potential for severe complications, diagnosis, and decision to initiate treatment should be based on clinical suspicion and confirmed by serologic tests. A therapeutic trial of tetracycline or chloramphenicol is indicated in patients in whom the diagnosis of scrub typhus is suspected. The recommended treatment regimen for scrub typhus is doxycycline. Alternative regimens include tetracycline, chloramphenicol, azithromycin, ciprofloxacin, rifampicin, and roxithromycin. Treatment of pregnant women with azithromycin was successfully done without relapse and with favorable pregnancy outcomes. Hence, early diagnosis and treatment are essential in order to reduce the mortality and the complications associated with the disease. We searched the English-language literature for reports of scrub typhus in children, pregnant women, and non-pregnant patients with scrub typhus, using the MEDLINE/PubMed database, which includes citations from 1945 to the present time. We used the search terms ‘scrub typhus’, ‘scrub typhus’ and ‘pregnancy’, ‘scrub typhus’ and ‘children’, ‘scrub typhus’ and ‘complications’, ‘scrub typhus’ and ‘treatment’. PMID:23825810
Nadjm, Behzad; Thuy, Pham T; Trang, Van D; Ha, Le Dang; Kinh, Nguyen V; Wertheim, Heiman F
2014-11-01
Scrub typhus is a common cause of fever in parts of South East and Southern Asia. Little is known about the disease burden in Vietnam. A 2-year observational study of scrub typhus at a tertiary referral hospital in northern Vietnam was carried out. Diagnosis was based on a single serological test in patients with suggestive clinical symptoms. Scrub typhus was diagnosed in 3.5% (251/7226) of admissions. Cases occurred throughout the year, with incidence highest in the summer. Although complications were common, mortality was low (1.2%; 3/251). These data suggest that scrub typhus is common, with a seasonal distribution in northern Vietnam. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.
A review of the global epidemiology of scrub typhus.
Xu, Guang; Walker, David H; Jupiter, Daniel; Melby, Peter C; Arcari, Christine M
2017-11-01
Scrub typhus is a serious public health problem in the Asia-Pacific area. It threatens one billion people globally, and causes illness in one million people each year. Caused by Orientia tsutsugamushi, scrub typhus can result in severe multiorgan failure with a case fatality rate up to 70% without appropriate treatment. The antigenic heterogeneity of O. tsutsugamushi precludes generic immunity and allows reinfection. As a neglected disease, there is still a large gap in our knowledge of the disease, as evidenced by the sporadic epidemiologic data and other related public health information regarding scrub typhus in its endemic areas. Our objective is to provide a systematic analysis of current epidemiology, prevention and control of scrub typhus in its long-standing endemic areas and recently recognized foci of infection.
A review of the global epidemiology of scrub typhus
Xu, Guang; Jupiter, Daniel; Melby, Peter C.; Arcari, Christine M.
2017-01-01
Scrub typhus is a serious public health problem in the Asia-Pacific area. It threatens one billion people globally, and causes illness in one million people each year. Caused by Orientia tsutsugamushi, scrub typhus can result in severe multiorgan failure with a case fatality rate up to 70% without appropriate treatment. The antigenic heterogeneity of O. tsutsugamushi precludes generic immunity and allows reinfection. As a neglected disease, there is still a large gap in our knowledge of the disease, as evidenced by the sporadic epidemiologic data and other related public health information regarding scrub typhus in its endemic areas. Our objective is to provide a systematic analysis of current epidemiology, prevention and control of scrub typhus in its long-standing endemic areas and recently recognized foci of infection. PMID:29099844
Comparison of Scrub Typhus Meningitis with Acute Bacterial Meningitis and Tuberculous Meningitis.
Kakarlapudi, Svas Raju; Chacko, Anila; Samuel, Prasanna; Verghese, Valsan Philip; Rose, Winsley
2018-01-15
To compare scrub typhus meningitis with bacterial and tuberculous meningitis. Children aged <15 years admitted with meningitis were screened and those who fit criteria for diagnosis of scrub typhus meningitis (n=48), bacterial meningitis (n=44) and tuberculous meningitis (n=31) were included for analysis. Clinical features, investigations and outcomes were compared between the three types of meningitis. Mean age, duration of fever at presentation, presence of headache and, altered sensorium and presence of hepatomegaly/splenomegaly were statistically significantly different between the groups. Scrub typhus had statistically significant thrombocytopenia, shorter hospital stay and a better neurological and mortality outcome. Sub-acute presentation of meningitis in older age group children, and good outcome is associated with scrub typhus when compared to bacterial and tuberculous meningitis.
Epidemiology of scrub typhus and the eschars patterns in South Korea from 2008 to 2012.
Park, Ji-Hyuk; Kim, Sun-Ja; Youn, Seung-Ki; Park, Kisoo; Gwack, Jin
2014-01-01
In South Korea, scrub typhus is the most common acute febrile illness in autumn. We analyzed scrub typhus cases reported from 2008 to 2012 to describe the epidemiology of scrub typhus as well as eschar patterns. A total of 30,478 cases were reported from 2008 to 2012; the incidence rates were higher in the southern and western regions of South Korea. The common clinical symptoms of confirmed scrub typhus cases from 2010 to 2012 were fever/chills (95.2%), eschars (78.9%), and myalgia (61.7%). The primary sites of eschars were the lower extremities (19.0%), abdomen/waist (13.4%), and axilla (11.5%) in men and the shoulder/frontal chest (15.1%), lower extremities (14.5%), and abdomen/waist (13.6%) in women. Regardless of gender, eschars tended to be more on the lower extremities among the leisure activities group. Among the occupational farm work group, who usually lived in rural areas, eschars appeared most frequently on the abdomen/waist in men and on the shoulder/frontal chest in women. Eschar patterns were influenced by gender and activities. These results could facilitate the prevention of scrub typhus and clarify the current status of scrub typhus in South Korea.
Jung, Ho-Chul; Chon, Sung-Bin; Oh, Won Sup; Lee, Dong-Hyun; Lee, Ho-Jin
2015-01-01
Scrub typhus usually presents as acute undifferentiated fever. This cross-sectional study included adult patients presenting with acute undifferentiated fever defined as any febrile illness for ≤ 14 days without evidence of localized infection. Scrub typhus cases were defined by an antibody titer of a ≥ fourfold increase in paired sera, a ≥ 1:160 in a single serum using indirect immunofluorescence assay, or a positive result of the immunochromatographic test. Multiple regression analysis identified predictors associated with scrub typhus to develop a prediction rule. Of 250 cases with known etiology of acute undifferentiated fever, influenza (28.0%), hepatitis A (25.2%), and scrub typhus (16.4%) were major causes. A prediction rule for identifying suspected cases of scrub typhus consisted of age ≥ 65 years (two points), recent fieldwork/outdoor activities (one point), onset of illness during an outbreak period (two points), myalgia (one point), and eschar (two points). The c statistic was 0.977 (95% confidence interval = 0.960–0.994). At a cutoff value ≥ 4, the sensitivity and specificity were 92.7% (79.0–98.1%) and 90.9% (86.0–94.3%), respectively. Scrub typhus, the third leading cause of acute undifferentiated fever in our region, can be identified early using the prediction rule. PMID:25448236
Kang, Seung-Ji; Jin, Hye-Mi; Won, Eun Jeong; Cho, Young-Nan; Jung, Hyun-Ju; Kwon, Yong-Soo; Kee, Hae Jin; Ju, Jae Kyun; Kim, Jung-Chul; Kim, Uh Jin; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook
2016-07-01
Mucosal-associated invariant T (MAIT) cells contribute to protection against certain microorganism infections. However, little is known about the role of MAIT cells in Orientia tsutsugamushi infection. Hence, the aims of this study were to examine the level and function of MAIT cells in patients with scrub typhus and to evaluate the clinical relevance of MAIT cell levels. Thirty-eight patients with scrub typhus and 53 health control subjects were enrolled in the study. The patients were further divided into subgroups according to disease severity. MAIT cell level and function in the peripheral blood were measured by flow cytometry. Circulating MAIT cell levels were found to be significantly reduced in scrub typhus patients. MAIT cell deficiency reflects a variety of clinical conditions. In particular, MAT cell levels reflect disease severity. MAIT cells in scrub typhus patients displayed impaired tumor necrosis factor (TNF)-α production, which was restored during the remission phase. In addition, the impaired production of TNF-α by MAIT cells was associated with elevated CD69 expression. This study shows that circulating MAIT cells are activated, numerically deficient, and functionally impaired in TNF-α production in patients with scrub typhus. These abnormalities possibly contribute to immune system dysregulation in scrub typhus infection.
Astrup, Elisabeth; Janardhanan, Jeshina; Otterdal, Kari; Ueland, Thor; Prakash, John A J; Lekva, Tove; Strand, Øystein A; Abraham, O C; Thomas, Kurien; Damås, Jan Kristian; Mathews, Prasad; Mathai, Dilip; Aukrust, Pål; Varghese, George M
2014-02-01
Scrub typhus, caused by Orientia tsutsugamushi, is endemic in the Asia-Pacific region. Mortality is high if untreated, and even with treatment as high as 10-20%, further knowledge of the immune response during scrub typhus is needed. The current study was aimed at comparing plasma levels of a variety of inflammatory mediators in scrub typhus patients and controls in South India in order to map the broader cytokine profile and their relation to disease severity and clinical outcome. We examined plasma levels of several cytokines in scrub typhus patients (n = 129) compared to healthy controls (n = 31) and infectious disease controls (n = 31), both in the acute phase and after recovery, by multiplex technology and enzyme immunoassays. Scrub typhus patients were characterized by marked changes in the cytokine network during the acute phase, differing not only from healthy controls but also from infectious disease controls. While most of the inflammatory markers were raised in scrub typhus, platelet-derived mediators such as RANTES were markedly decreased, probably reflecting enhanced platelet activation. Some of the inflammatory markers, including various chemokines (e.g., interleukin-8, monocyte chemoattractant peptide-1 and macrophage inflammatory protein-1β) and downstream markers of inflammation (e.g., C-reactive protein and pentraxin-3), were also associated with disease severity and mortality during follow-up, with a particular strong association with interleukin-8. Our findings suggest that scrub typhus is characterized by a certain cytokine profile that includes dysregulated levels of a wide range of mediators, and that this enhanced inflammation could contribute to disease severity and clinical outcome.
Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo
2016-01-01
Scrub typhus is an infectious disease caused by Orientia tsutsugamushi-induced systemic vasculitis, but the involvement of the gastrointestinal tract and the endoscopic findings associated with scrub typhus are not well understood. We performed a prospective study and recommend performing esophagogastroduodenoscopy (EGD) for all possible scrub typhus patients, regardless of gastrointestinal symptoms. Gastrointestinal symptoms, endoscopic findings and clinical severity based on organ involvement and ICU admission were analyzed. Gastrointestinal symptoms occurred in up to 76.4% of scrub typhus patients. The major endoscopic findings were ulcers (43/127, 33.9%). Interestingly, 7.1% (9/127) of the patients presented with esophageal candidiasis. There was no correlation between the presence or absence of gastrointestinal symptoms and the endoscopic grade (P = 0.995). However, there was a positive correlation between the clinical severity and the endoscopic findings (P = 0.001). Sixty-three percent of the patients presented with erosion or ulcers on prospectively performed endoscopic evaluations, irrespective of gastrointestinal symptoms. Gastrointestinal symptoms did not reflect the need for endoscopy. Scrub typhus patients could have significant endoscopic abnormalities even in the absence of gastrointestinal symptoms.
Rizvi, Meher; Sultan, Asfia; Chowdhry, Madhav; Azam, Mohd; Khan, Fatima; Shukla, Indu; Khan, Haris M
2018-01-01
Scrub typhus is lesser known cause of fever of unknown origin in India. Even if there have been reports documenting the prevalence of scrub typhus in different parts of India, it is still an unknown entity, and clinicians usually do not consider it as differential diagnosis. The present study was performed to document the prevalence of scrub typhus among febrile patients in western part of Uttar Pradesh and to assess the clinical profile of infected patients on the one hand and knowledge, attitude, and practices among clinicians on the other. A total of 357 adult patients with fever of more than 5-day duration were recruited. All patients underwent complete physical examination, and detailed clinical history was elicited as per predesigned pro forma. After primary screening to rule out malaria, enteric fever, and leptospirosis infection, secondary screening for scrub typhus was done by rapid screen test and IgM ELISA. Scrub typhus infection was positive in 91 (25.5%) cases. The most common symptoms among the patients were fever (100%), pain in abdomen (79.1%), pedal edema 56 (61.5%), rash 44 (48.3%), headache 44 (48.3%), vomiting 42 (46.1%), constipation 33 (36.2%), cough 28 (30.7%), and lymphadenopathy 20 (21.9%). The median values of interleukin-8, interferon-gamma, and tumor necrosis factor-alpha in healthy controls were 15.54 pg/ml, 7.77 pg/ml, and 54.1 pg/ml, respectively, while the median values of these cytokines in scrub typhus-positive patients were 21.04 pg/ml, 8.74 pg/ml, and 73.8 pg/ml, respectively. Our results highlight that scrub typhus infection is an important cause of pyrexia of unknown origin, and active surveillance is necessary to assess the exact magnitude and distribution of the disease.
[Epidemiology of scrub typhus and influencing factors in Yunnan province, 2006-2013].
Sun, Y; Shi, C; Li, X L; Fang, L Q; Cao, W C
2018-01-10
Objective: To understand the epidemiological characteristics of scrub typhu s and influencing factors in Yunnan province, and provide further information for the prevention and control of scrub typhus. Methods: Based on the incidence data of scrub typhus reported in Yunnan from 2006 to 2013, the epidemiological characteristics of scrub typhus were analyzed and related environmental factors were identified with panel negative binomial regression model. Results: A total of 8 980 scrub typhus cases were reported during 2006-2013 in Yunnan. The average annual incidence was 2.46/100 000, with an uptrend observed. Natural focus expansion was found, affecting 71.3% of the counties in 2013. The epidemic mainly occurred in summer and autumn with the incidence peak during July-October. The annual incidence was higher in females than in males. More cases occurred in children and farmers, the proportions of cases in farmers and pre-school aged children showed an obvious increase. Panel negative binomial regression model indicated that the transmission risk of scrub typhus was positive associated with monthly temperature and monthly relative humidity. Furthermore, an "U" pattern between the risk and the increased coverage of cropland and grassland as well as an "inverted-U" pattern between the risk and increased coverage of shrub were observed. Conclusion: It is necessary to strengthen the scrub typhus surveillance in warm and moist areas as well as the areas with high coverage of cropland and grassland in Yunnan, and the health education in children and farmers who are at high risk.
2010-09-01
Korean J Paras/to/. Vol. 48, No. 3: 237-243, September 2010 DOl: JO.J3471kjp.2010.48.J.237 Serosurveillance of Scrub Typhus in Small Mammals...65th Medical BrigadeAJSAMEDDAC-Korea, Unit# 15281, APO AP 96205-5281, USA Abstract: Comprehensive quarterly serosurveillance on scrub typhus in small...rarely observed (prevalence < 1 0%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4
Won, Eun Jeong; Cho, Young-Nan; Jung, Hyun-Ju; Kwon, Yong-Soo; Kee, Hae Jin; Ju, Jae Kyun; Kim, Jung-Chul; Kim, Uh Jin; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook
2016-01-01
Background Mucosal-associated invariant T (MAIT) cells contribute to protection against certain microorganism infections. However, little is known about the role of MAIT cells in Orientia tsutsugamushi infection. Hence, the aims of this study were to examine the level and function of MAIT cells in patients with scrub typhus and to evaluate the clinical relevance of MAIT cell levels. Methodology/Principal Findings Thirty-eight patients with scrub typhus and 53 health control subjects were enrolled in the study. The patients were further divided into subgroups according to disease severity. MAIT cell level and function in the peripheral blood were measured by flow cytometry. Circulating MAIT cell levels were found to be significantly reduced in scrub typhus patients. MAIT cell deficiency reflects a variety of clinical conditions. In particular, MAT cell levels reflect disease severity. MAIT cells in scrub typhus patients displayed impaired tumor necrosis factor (TNF)-α production, which was restored during the remission phase. In addition, the impaired production of TNF-α by MAIT cells was associated with elevated CD69 expression. Conclusions This study shows that circulating MAIT cells are activated, numerically deficient, and functionally impaired in TNF-α production in patients with scrub typhus. These abnormalities possibly contribute to immune system dysregulation in scrub typhus infection. PMID:27463223
Scrub Typhus: An Emerging Neglected Tropical Disease in Nepal.
Upadhyaya, B P; Shakya, G; Adhikari, S; Rijal, N; Acharya, J; Maharjan, L; Marasini, B R
2016-05-01
Scrub typhus is a neglected tropical disease and is under reported from Nepal. The objective of this study was to investigate the sero-epidemiology of scrub typhus in patients suffering from acute febrile illness. A total of 434 specimens collected from July to November 2015 at National Public Health Laboratory (NPHL) were investigated for detection of immunoglobulin M (IgM) antibody to Orientiatsutsugamushi.The Scrub Typhus Detect TM kit (InBios, USA) was used to detect the antibodies to O.tsutsugamushi in human serum. Randomly selected 10% positive specimens were used for confirmation by dot- enzyme-linked immunosorbent assay and indirect immunofluorescence assay. Of the total, 175 (40.3%) were positive for IgM antibodies to O. tsutsugamushi. Positive results of scrub typhus were highest among female in 11-20 year followed by males in 41-50 years age group. The IgM antibodies to O. tsutusugamushi were positive in specimens of various geographical regions including 30 districts of Nepal. Positive cases were found in various ecological regions of Nepal. Scrub typhus is one of the neglected tropical diseases in Nepal. Patients with acute febrile illness should be investigated for scrub typhus with high priority. There is an urgent need of reliable and affordable diagnostic tests at all level of health facilities of Nepal. Surveillance and public health awareness about the disease transmission and preventive measures needs to be initiated.
Seroprevalence of Scrub Typhus Infection in Arunachal Pradesh, India.
Jakharia, Aniruddha; Borkakoty, Biswajyoti; Biswas, Dipankar; Yadav, Kaushal; Mahanta, Jagadish
2016-10-01
Scrub typhus is a major reason for febrile illness, caused by a bacterium Orientia tsutsugamushi, a rickettsial pathogen. Few outbreaks of scrub typhus have been reported from Arunachal Pradesh in recent past. However, there is lack of seroprevalence data from the region. In this regard, this study was undertaken using archival serum sample available from seven districts of Arunachal Pradesh. This serological study was conducted in Regional Medical Research Center for NE Region, Dibrugarh. Reactivity to IgG class of antibodies against scrub typhus was done using Scrub typhus detect IgG ELISA kit as per manufacturer's protocol. Seroprevalence of scrub typhus in seven districts of Arunachal Pradesh was found to be 40% (120/300). The age-specific scrub typhus seroprevalence rose steadily from 5.6% in children <10 years of age to 61.8% in persons aged ≥40 years (p = 0.0001). Prevalence is lowest in Papumpare (25.9%) and highest in East Siang (72.5%) (p = 0.0001). The seroprevalence in males and females was very similar, however, the female prevalence increases from age group ≥30 years (p = 0.053). Moreover, among the farmers, the seroprevalence is higher (58.3%) (p = 0.0001). As clinical symptoms overlap with other viral/bacterial infections, scrub typhus infection should be considered in differential diagnosis of any acute febrile illness in this part of the country. In view of the high prevalence, empirical therapy of doxycycline/azithromycin may be done in cases of undiagnosed fever. Active surveillance has to be done to understand exact magnitude, epidemiological aspects, and distribution of vector and disease of this reemerging neglected tropical disease.
Chin, Jung Yeon; Kang, Ki-Woon; Moon, Kyung Min; Kim, Jongwoo; Choi, Yu Jeong
2018-03-01
Scrub typhus is known as a self-limited infectious disease. Cardiac complication is uncommon and usually not life-threatening. Until now, few cases of fulminant myocarditis by scrub typhus have been reported. So, we investigated incidence and predictors of acute myocarditis in severe scrub typhus. We retrospectively reviewed 89 patients among 91 scrub typhus confirmed patients who examined an echocardiogram and cardiac biomarkers from 2005 to 2015 in the intensive care unit at our hospital. We excluded two patients who didn't have electrocardiography. Patients were divided into two groups and compared between scrub typhus with (n = 13) and without (n = 76) acute myocarditis. Age, sex, and underlying diseases were similar between the groups. The existence of eschar and duration of general ache and fever were similar between the groups. However, patients with acute myocarditis had more elevated total bilirubin, high incidence of ST elevations and paroxysmal atrial fibrillation (PAF) than those without acute myocarditis. Receiver operating characteristic analysis showed that the PAF was a predictor of myocarditis with a sensitivity of 70% and specificity of 84%. Predictive power of combination of ST-segment elevation and PAF was significantly associated with myocarditis in the multivariate analysis (odds ratio, 1.57; 95% confidence interval [CI], 1.21 to 11.7; p = 0.041) and area under the curve was 0.947 (95% CI, 0.878 to 0.983; p < 0.001). Acute myocarditis with scrub typhus may be more common than previously reported. Patients with high bilirubin and PAF are at increased risk of acute myocarditis with scrub typhus. These patients warrant closer follow-up and echocardiogram would be needed.
Chin, Jung Yeon; Kang, Ki-Woon; Moon, Kyung Min; Kim, Jongwoo; Choi, Yu Jeong
2018-01-01
Background/Aims Scrub typhus is known as a self-limited infectious disease. Cardiac complication is uncommon and usually not life-threatening. Until now, few cases of fulminant myocarditis by scrub typhus have been reported. So, we investigated incidence and predictors of acute myocarditis in severe scrub typhus. Methods We retrospectively reviewed 89 patients among 91 scrub typhus confirmed patients who examined an echocardiogram and cardiac biomarkers from 2005 to 2015 in the intensive care unit at our hospital. We excluded two patients who didn’t have electrocardiography. Patients were divided into two groups and compared between scrub typhus with (n = 13) and without (n = 76) acute myocarditis. Results Age, sex, and underlying diseases were similar between the groups. The existence of eschar and duration of general ache and fever were similar between the groups. However, patients with acute myocarditis had more elevated total bilirubin, high incidence of ST elevations and paroxysmal atrial fibrillation (PAF) than those without acute myocarditis. Receiver operating characteristic analysis showed that the PAF was a predictor of myocarditis with a sensitivity of 70% and specificity of 84%. Predictive power of combination of ST-segment elevation and PAF was significantly associated with myocarditis in the multivariate analysis (odds ratio, 1.57; 95% confidence interval [CI], 1.21 to 11.7; p = 0.041) and area under the curve was 0.947 (95% CI, 0.878 to 0.983; p < 0.001). Conclusions Acute myocarditis with scrub typhus may be more common than previously reported. Patients with high bilirubin and PAF are at increased risk of acute myocarditis with scrub typhus. These patients warrant closer follow-up and echocardiogram would be needed. PMID:28226202
Astrup, Elisabeth; Janardhanan, Jeshina; Otterdal, Kari; Ueland, Thor; Prakash, John A. J.; Lekva, Tove; Strand, Øystein A.; Abraham, O. C.; Thomas, Kurien; Damås, Jan Kristian; Mathews, Prasad; Mathai, Dilip; Aukrust, Pål; Varghese, George M.
2014-01-01
Background Scrub typhus, caused by Orientia tsutsugamushi, is endemic in the Asia-Pacific region. Mortality is high if untreated, and even with treatment as high as 10–20%, further knowledge of the immune response during scrub typhus is needed. The current study was aimed at comparing plasma levels of a variety of inflammatory mediators in scrub typhus patients and controls in South India in order to map the broader cytokine profile and their relation to disease severity and clinical outcome. Methodology/Principal Findings We examined plasma levels of several cytokines in scrub typhus patients (n = 129) compared to healthy controls (n = 31) and infectious disease controls (n = 31), both in the acute phase and after recovery, by multiplex technology and enzyme immunoassays. Scrub typhus patients were characterized by marked changes in the cytokine network during the acute phase, differing not only from healthy controls but also from infectious disease controls. While most of the inflammatory markers were raised in scrub typhus, platelet-derived mediators such as RANTES were markedly decreased, probably reflecting enhanced platelet activation. Some of the inflammatory markers, including various chemokines (e.g., interleukin-8, monocyte chemoattractant peptide-1 and macrophage inflammatory protein-1β) and downstream markers of inflammation (e.g., C-reactive protein and pentraxin-3), were also associated with disease severity and mortality during follow-up, with a particular strong association with interleukin-8. Conclusions/Significance Our findings suggest that scrub typhus is characterized by a certain cytokine profile that includes dysregulated levels of a wide range of mediators, and that this enhanced inflammation could contribute to disease severity and clinical outcome. PMID:24516677
Comparison of minocycline and azithromycin for the treatment of mild scrub typhus in northern China.
Zhao, Minxing; Wang, Ting; Yuan, Xiaoyu; Du, Weiming; Lin, Miaoxin; Shen, Yanbo
2016-09-01
Scrub typhus, caused by Orientia tsutsugamushi, has recently emerged in northern China where the disease had not been known to exist. Although doxycycline and azithromycin are the recommended agents for the treatment of scrub typhus, clinical responses depend both on the susceptibilities of various O. tsutsugamushi strains and the severity of the disease. A retrospective analysis was conducted on patients diagnosed with mild scrub typhus from August 2013 to January 2016 in the Affiliated Hospital of Nantong University, northern China. A total of 40 patients who received minocycline treatment and 34 patients who received azithromycin treatment were included in the analysis. All patients except one defervesced within 120 h after initiating antimicrobial therapy. Kaplan-Meier curves in association with log-rank test showed that the median time to defervescence was significantly shorter for the minocycline-treated group than the azithromycin-treated group (P = 0.003). There were no serious adverse events during treatment. No relapse occurred in either group during the 1-month follow-up period. In conclusion, both minocycline and azithromycin are effective and safe for the treatment of mild scrub typhus, but minocycline is more active than azithromycin against O. tsutsugamushi infection acquired in northern China. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.
Scrub typhus: radiological and clinical findings in abdominopelvic involvement.
Kim, Kun Yung; Song, Ji Soo; Park, Eun Hae; Jin, Gong Yong
2017-03-01
To describe the clinical and radiological findings of abdominopelvic involvement in scrub typhus. Abdominopelvic computed tomography (CT) of 78 patients with scrub typhus were evaluated by two readers. The presence of gallbladder wall thickening, arterial inhomogeneous enhancement of the liver, periportal edema, splenic infarction, hepatomegaly, splenomegaly, ascites, pleural effusion, and sites of lymphadenopathy were evaluated. Patients were divided into four clinical subgroups according to laboratory findings. Association between imaging findings and subgroups was analyzed by Chi squared test or Fisher's exact test. The most common CT finding was hepatomegaly (74.4%), followed by splenomegaly (66.7%). The majority of patients had at least three areas of abdominopelvic lymphadenopathy (71.8%). Pelvic lymphadenopathy was most commonly seen when eschar was found in the ipsilateral lower extremity (left, n = 5/7; right, n = 8/13). Significant association between hepatic dysfunction and perigastric lymphadenopathy was documented (p = 0.03). Scrub typhus has a spectrum of variable clinical and radiological findings mimicking those of acute hepatitis. Diffuse abdominopelvic lymphadenopathy involving the retroperitoneum and pelvic area may aid in early diagnosis of scrub typhus. Perigastric lymphadenopathy could be a sign of severe scrub typhus combined with hepatic dysfunction.
Usha, K; Kumar, E; Kalawat, Usha; Kumar, B Siddhartha; Chaudhury, A; Gopal, D V R Sai
2016-10-01
Scrub typhus is a vector-borne zoonotic infection caused by Orientiatsutsugamushi. Local epidemiology of the circulating serotypes of scrub typhus is not available from most parts of India. We conducted this study for the diagnosis of scrub typhus using IgM ELISA and to detect O. tsutsugamushi serotypes circulating in southern Andhra Pradesh, India. Samples were collected from patients clinically suspected to have scrub typhus and were subjected to IgM ELISA to measure IgM antibodies against O. tsutsugamushi. Nested polymerase chain reaction (PCR) was performed targeting strain-specific regions in ELISA-positive samples. Of a total of 663 samples, 258 (38.91%) were found to be positive by IgM ELISA. Serotypes could be detected in 230 (34.69%) samples only. Only two serotypes, Karp and Kawasaki, were found in the serum samples, with the former being predominant. The dual infection of Karp and Kawasaki serotypes was found in seven patients. Other serotypes such as Gilliam, Kuroki and Kato were not detected in the samples. The nested PCR products proved useful in presumptively identifying the endemic O. tsutsugamushi serotypes. The present study could be significant in understanding scrub typhus epidemiology in this region.
Scrub typhus associated hepatic dysfunction and abdominal CT findings
Park, Man Je; Lee, Hyoun Soo; Shim, Sang Goon; Kim, So Hee
2015-01-01
Objective: This retrospective study investigated abnormal hepatic dysfunction and abdominal computed tomography (CT) findings in scrub typhus. Methods: Three hundred forty nine adult patients were diagnosed with scrub typhus. Ninety four underwent abdominal CT. The CT images were reviewed by the attending radiologist. Patient data of history, symptoms, signs, and results of laboratory tests were collected from the electronic medical records. Results: In 349 patients with scrub typhus, elevation of aspartate aminotransferase (78.5%) and alanine aminotransferase (63.0%) were dominant compared to alkaline phosphatase (27.2%) and total bilirubin (16.1%). Abdominal CT findings of 94 patients were, in descending order of frequency, enlarged lymph node (53.2%), inhomogeneous enhancement of liver (47.9%), splenomegaly (46.8%), ascites (28.7%), low attenuation of periportal areas (27.7%), gallbladder wall thickening (17.0%), and splenic infarct (6.4%). Also, the level of aspartate aminotransferase tended to be elevated according to the number of CT findings (P= 0.028) Conclusions: We found that abdominal CT manifestations of scrub typhus with elevated aminotransferases were varied and not specific. However, knowledge of these findings may evoke the recognition of scrub typhus by clinicians in endemic areas. PMID:26101478
Lee, Jun; Kim, Dong-Min; Yun, Na Ra; Kim, Young Dae; Park, Chan Guk; Kim, Man Woo
2016-01-01
Scrub typhus is an infectious disease caused by Orientia tsutsugamushi-induced systemic vasculitis, but the involvement of the gastrointestinal tract and the endoscopic findings associated with scrub typhus are not well understood. We performed a prospective study and recommend performing esophagogastroduodenoscopy (EGD) for all possible scrub typhus patients, regardless of gastrointestinal symptoms. Gastrointestinal symptoms, endoscopic findings and clinical severity based on organ involvement and ICU admission were analyzed. Gastrointestinal symptoms occurred in up to 76.4% of scrub typhus patients. The major endoscopic findings were ulcers (43/127, 33.9%). Interestingly, 7.1% (9/127) of the patients presented with esophageal candidiasis. There was no correlation between the presence or absence of gastrointestinal symptoms and the endoscopic grade (P = 0.995). However, there was a positive correlation between the clinical severity and the endoscopic findings (P = 0.001). Sixty-three percent of the patients presented with erosion or ulcers on prospectively performed endoscopic evaluations, irrespective of gastrointestinal symptoms. Gastrointestinal symptoms did not reflect the need for endoscopy. Scrub typhus patients could have significant endoscopic abnormalities even in the absence of gastrointestinal symptoms. PMID:27195943
Use of Multiplex Real-Time PCR To Diagnose Scrub Typhus.
Tantibhedhyangkul, Wiwit; Wongsawat, Ekkarat; Silpasakorn, Saowaluk; Waywa, Duangdao; Saenyasiri, Nuttawut; Suesuay, Jintapa; Thipmontree, Wilawan; Suputtamongkol, Yupin
2017-05-01
Scrub typhus, caused by Orientia tsutsugamushi , is a common cause of acute undifferentiated febrile illness in the Asia-Pacific region. However, its nonspecific clinical manifestation often prevents early diagnosis. We propose the use of PCR and serologic tests as diagnostic tools. Here, we developed a multiplex real-time PCR assay using hydrolysis (TaqMan) probes targeting O. tsutsugamushi 47-kDa, groEL , and human interferon beta (IFN-β gene) genes to improve early diagnosis of scrub typhus. The amplification efficiency was higher than 94%, and the lower detection limit was 10 copies per reaction. We used a human gene as an internal DNA quality and quantity control. To determine the sensitivity of this PCR assay, we selected patients with confirmed scrub typhus who exhibited a clear 4-fold increase in the level of IgG and/or IgM. The PCR assay result was positive in 45 of 52 patients, indicating a sensitivity of 86.5% (95% confidence interval [CI]: 74.2 to 94.4). The PCR assessment was negative for all 136 non-scrub typhus patients, indicating a specificity of 100% (95% CI: 97.3 to 100). In addition, this test helped diagnose patients with inconclusive immunofluorescence assay (IFA) results and using single blood samples. In conclusion, the real-time PCR assay proposed here is sensitive and specific in diagnosing scrub typhus. Combining PCR and serologic tests will improve the diagnosis of scrub typhus among patients presenting with acute febrile illness. Copyright © 2017 American Society for Microbiology.
Clinical Evaluation of Rapid Diagnostic Test Kit for Scrub Typhus with Improved Performance.
Kim, Young-Jin; Park, Sungman; Premaratna, Ranjan; Selvaraj, Stephen; Park, Sang-Jin; Kim, Sora; Kim, Donghwan; Kim, Min Soo; Shin, Dong Hoon; Choi, Kyung-Chan; Kwon, Soon-Hwan; Seo, Wonjun; Lee, Nam Taek; Kim, Seung-Han; Kang, Heui Keun; Kim, Yoon-Won
2016-08-01
Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus.
1980-01-01
Rocky Mountain spotted fever (3, 12, 20, 30), typhus, and scrub typhus rickettsiae. In a sum- and scrub typhus (38). Many, however, were mary and...and M. J. Synder. 197ti murine typhus in sera from Indonesians. Trans. R. ’.oc. Prompt confirmation of Rocky Mountain spotted fever "Trop. Med Hyg
Endemic Scrub Typhus in South America.
Weitzel, Thomas; Dittrich, Sabine; López, Javier; Phuklia, Weerawat; Martinez-Valdebenito, Constanza; Velásquez, Katia; Blacksell, Stuart D; Paris, Daniel H; Abarca, Katia
2016-09-08
Scrub typhus is a life-threatening zoonosis caused by Orientia tsutsugamushi organisms that are transmitted by the larvae of trombiculid mites. Endemic scrub typhus was originally thought to be confined to the so called "tsutsugamushi triangle" within the Asia-Pacific region. In 2006, however, two individual cases were detected in the Middle East and South America, which suggested that the pathogen was present farther afield. Here, we report three autochthonous cases of scrub typhus caused by O. tsutsugamushi acquired on Chiloé Island in southern Chile, which suggests the existence of an endemic focus in South America. (Funded by the Chilean Comisión Nacional de Investigación Científica y Tecnológica and the Wellcome Trust.).
The genotypes of Orientia tsutsugamushi, identified in scrub typhus patients in northern Vietnam.
Nguyen, Hang L K; Pham, Hang T T; Nguyen, Tinh V; Hoang, Phuong Vm; Le, Mai T Q; Takemura, Taichiro; Hasebe, Futoshi; Hayasaka, Daisuke; Yamada, Akio; Hotta, Kozue
2017-03-01
There are an estimated one million patients with scrub typhus in the Asia-Pacific region. There are few reports describing the incidence of scrub typhus in Vietnam. Blood samples collected from 63 patients clinically diagnosed as having scrub typhus from July 2015 to September 2016 were subjected to genotyping of Orientia tsutsugamushi. Of these patients, 42 (67%) tested positive for O. tsutsugamushi, and the most common genotype was identified to be Karp (55%). Other genotypes, TA763, Gilliam type in Japan variant, and Kato were also found in 17%, 17% and 12% of patients, respectively. To better understand the epidemiological landscape of scrub typhus in Vietnam, a countrywide study is needed. LC110330-LC110333, LC110336-LC110351 and LC214804-LC214825. © The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Rawat, Vinita; Singh, Rajesh Kumar; Kumar, Ashok; Saxena, Sandip R; Varshney, Umesh; Kumar, Mukesh
2018-04-01
We analysed the epidemiology, clinical and laboratory data of the 168 scrub typhus cases confirmed by a combination of any one of the following: real time polymerase chain reaction (RT-PCR) and/or immunofluorescence assay (IFA) (IgM and/or IgG). The peak season for scrub typhus was from July to October. By multivariate binary logistic regression analysis, the risk of scrub typhus was about four times in those working in occupation related to forest work. Major clinical manifestations were fever (100%), myalgia (65%), cough (51%) and vomiting (46%); major complications were meningitis/meningoencephatilitis (12.5%) and multi-organ failure (MOF) and pneumonia (5.3% each). Laboratory investigations revealed raised aminotranferase levels and thrombocytopenia in most confirmed cases. We conclude that scrub typhus is an important cause of febrile illness in the Kumaon hills of Uttarakhand where this disease had not previously been considered to exist.
[Case of imported scrub typhus contracted in Myanmar].
Matsumura, Yasufumi; Shimizu, Tsunehiro
2009-05-01
Scrub typhus is widespread in rural south and southeastern Asia and the western Pacific. The scrub typhus incidence is the highest among vector-borne diseases in Japan, but imported cases are extremely rare. A 49-year-old man admitted for persistent fever, headache, and rash after returning from Myanmar had been exposed to mosquito and tick bites while doing a 12-day forest inventory in Myanmar. On admission, he had a generalized maculopapular rash but no apparent eschars characteristic of scrub typhus. Blood examination and abdominal ultrasonography showed elevated liver enzymes, thrombocytopenia, and hepatosplenomegaly. Repeated blood smears and blood cultures were negative for malaria infection and bacteremia. Dengue fever was denied by both PCR and serology. The patient deteriorated on the ninth day and suffered complications of rhabdomyolysis, pneumonia, and enteritis. Based on a tentative diagnosis of typhoid fever or rickettiosis, we administratered ceftriaxone and minocycline, which dramatically reduced clinical signs and symptoms. After discharge on day 19, immunofluorescence assay showed significantly increased antibodies for Orienta tsutsugamushi serotype Gilliam, first discovered in Myanmar. All serological results were negative for other rickettioses, leptospirosis and Q fever. Given the many travelers from Japan visiting endemic scrub typhus areas, we must recognize cases of imported scrub typhus among those travelers with fever and rash returning from endemic areas.
Prakash, J A J; Kavitha, M L; Mathai, E
2011-01-01
Scrub typhus is a zoonotic illness endemic in the Asia-Pacific region. Early diagnosis and appropriate management contribute significantly to preventing adverse outcomes including mortality. Serology is widely used for diagnosing scrub typhus. Recent reports suggest that polymerase chain reaction (PCR) could be a rapid and reliable alternative. This study assessed the utility of these tests for scrub typhus diagnosis. Nested PCR to detect the 56 kDa antigen gene of O. tsutsugamushi was performed on blood clots from 87 individuals with clinically suspected scrub typhus. Weil-Felix test and scrub typhus IgM ELISA were performed on serum samples from the same patients. As a gold standard reference test was not available, latent class analysis (LCA) was used to assess the performance of the three tests. The LCA analysis showed the sensitivity of Weil-Felix test, IgM ELISA and PCR to be 59%, 100% and 58% respectively. The specificity of ELISA was only 73%, whereas those of the Weil-Felix test and PCR were 94% and 100% respectively. Nested PCR using blood clots while specific, lacked sensitivity as compared to IgM ELISA. In resource-poor settings Weil-Felix test still remains valuable despite its moderate sensitivity.
Clinical proteomic analysis of scrub typhus infection.
Park, Edmond Changkyun; Lee, Sang-Yeop; Yun, Sung Ho; Choi, Chi-Won; Lee, Hayoung; Song, Hyun Seok; Jun, Sangmi; Kim, Gun-Hwa; Lee, Chang-Seop; Kim, Seung Il
2018-01-01
Scrub typhus is an acute and febrile infectious disease caused by the Gram-negative α-proteobacterium Orientia tsutsugamushi from the family Rickettsiaceae that is widely distributed in Northern, Southern and Eastern Asia. In the present study, we analysed the serum proteome of scrub typhus patients to investigate specific clinical protein patterns in an attempt to explain pathophysiology and discover potential biomarkers of infection. Serum samples were collected from three patients (before and after treatment with antibiotics) and three healthy subjects. One-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis followed by liquid chromatography-tandem mass spectrometry was performed to identify differentially abundant proteins using quantitative proteomic approaches. Bioinformatic analysis was then performed using Ingenuity Pathway Analysis. Proteomic analysis identified 236 serum proteins, of which 32 were differentially expressed in normal subjects, naive scrub typhus patients and patients treated with antibiotics. Comparative bioinformatic analysis of the identified proteins revealed up-regulation of proteins involved in immune responses, especially complement system, following infection with O. tsutsugamushi , and normal expression was largely rescued by antibiotic treatment. This is the first proteomic study of clinical serum samples from scrub typhus patients. Proteomic analysis identified changes in protein expression upon infection with O. tsutsugamushi and following antibiotic treatment. Our results provide valuable information for further investigation of scrub typhus therapy and diagnosis.
Scrub typhus re-emergence in India: Contributing factors and way forward.
Ranjan, Jai; Prakash, John Antony Jude
2018-06-01
Scrub typhus is a mite borne infectious disease which has re-emerged in India in the 3rd millennium after years of quiescence. In this review, the authors hypothesize the various factors responsible for resurgence of this disease. The main drivers that could have contributed to the upsurge in scrub typhus cases in past two decades are changes in land use land cover (LULC) and urbanisation which are; as a result of the population explosion, causing a strain on sanitation and also increased diversion of forest land for agricultural use. In addition, the availability of better tests, changes in antimicrobial use, climate change also could have impacted the epidemiology, which is showing an upward trend as is evidenced by increasing reports and concomitant publications from India on scrub typhus. Scrub typhus cases are supposed to increase in the coming years as factors like global warming, urbanisation, changes in LULC and rise in AMR (anti-microbial resistance) will be difficult or impossible to control. Therefore, increasing awareness of public and health care professionals regarding scrub typhus coupled with availability of rapid diagnostic assays and implementation of appropriate treatment protocols for control of AFI (acute febrile illness) especially at the community level will help mitigate the scenario in the long run. Copyright © 2018. Published by Elsevier Ltd.
Diagnostic validation of selected serological tests for detecting scrub typhus.
Koraluru, Munegowda; Bairy, Indira; Varma, Muralidhar; Vidyasagar, Sudha
2015-07-01
Clinical diagnosis of scrub typhus is often difficult because the symptoms are very similar to those of other febrile illness such as dengue, leptospirosis, malaria and other viral hemorrhagic fevers. Though better diagnostic tests are available for rickettsial diseases and scrub typhus elsewhere, the Weil-Felix test is still commonly used in India, mainly because microimmunofluorescence assays (M-IFA) were not available in India till recently and relevant staff had insufficient training. The present study was performed to investigate the performance of M-IFA, IgM ELISA, and Weil-Felix test on 546 non-repeated serum samples from subjects suspected of having scrub typhus. One hundred and forty-three of these 546 samples were positive by M-IFA; these cases were also confirmed clinically to have scrub typhus based on their dramatic responses to doxycycline therapy. IgM ELISA was positive in 122 of the 143 M-IFA positive cases and the Weil-Felix test in 96. Though the Weil-Felix test is a heterophile agglutination test, it was found in this study to have good specificity but far too little sensitivity to use as a routine diagnostic test. IgM ELISA can be a good substitute for M-IFA. Incorporation of multiple prototype antigens on M-IFA slides is likely one of the reasons for its superior performance. As newer and better diagnostic assays become available for scrub typhus diagnosis in developed countries, it will be imperative to also use such tests in other endemic countries to prevent over- or under-diagnosis of scrub typhus. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.
The clinical characteristics of pleural effusion in scrub typhus.
Kim, Hyung Ho; Chung, Jong-Hoon; Kim, Dong-Min; Yun, Na Ra; Lee, Jun; Kwon, Yong Eun; Yoon, Sung Ho; Lee, Seung Il; Han, Mi Ah
2016-06-11
The aim of this study is to identify the factors associated with the occurrence of pleural effusion and to investigate the characteristics of pleural effusion in scrub typhus. We conducted a retrospective analysis of the medical records of scrub typhus patients between January 2004 and December 2011 at Chosun University Hospital in South Korea. A total of 445 scrub typhus patients were divided into the following two groups: without (n = 352) or with pleural effusion (n = 93). The data of 18 scrub typhus patients who underwent thoracentesis were summarized. Multivariate analysis demonstrated that the following factors were associated with the occurrence of pleural effusion in scrub typhus: older age (odds ratio [OR] = 1.029, P = 0.037, confidence interval [CI] = 1.002-1.056); male gender (OR = 1.924, P = 0.020, CI = 1.109-3.340); presence of heart failure (OR = 2.628, P = 0.039, CI = 1.052-6.565); and lower albumin (OR = 0.107, P ≤ 0.001, CI = 0.058-0.196). Most pleural effusion presentations were bilateral (88 %) and small (91 %). The effusion had transudate characteristics in 7 patients and exudate characteristics in 11 patients based on Light's criteria. This study provided the first data regarding the following four independent risk factors associated with the occurrence of pleural effusion: older age; male gender; the presence of heart failure; and lower albumin. The pleural effusion presentations in scrub typhus patients were bilateral and small in most cases, with transudate and/or exudate characteristics.
Scrub typhus in rural Rajasthan and a review of other Indian studies.
Masand, Rupesh; Yadav, Ritesh; Purohit, Alok; Tomar, Balvir Singh
2016-05-01
Scrub typhus is an acute febrile illness which has been reported from various parts of India with Rajasthan recently joining the list of affected states. To report a series of paediatric scrub typhus cases from rural Rajasthan. Retrospective review of children with scrub typhus admitted to the wards and paediatric intensive care unit (PICU) of a tertiary-care hospital. The study was undertaken over an 8-month period from May to December 2013. All patients with a clinical presentation and/or serological confirmation of scrub typhus who tested negative for malaria, enteric fever, dengue, leptospirosis and urinary tract infection (UTI) were included. A range of investigations were undertaken including IgM-ELISA for scrub typhus, followed by appropriate medical management. Thirty patients satisfied the inclusion criteria. The mean (SD, range) age of the patients was 8·56 (3·43, 3-16) years. The most common clinical features were fever (n = 30, 100%), headache (n = 20, 66%), myalgia (n = 15, 50%), hepatosplenomegaly (n = 18, 60%) and pallor (n = 5, 16%). Typical features such as eschar and rash were observed in only one (3·3%) and three (10%) patients, respectively; none had generalised lymphadenopathy or conjunctival congestion. IgM-ELISA for scrub typhus was positive in 28 patients (93·3%) and 27 responded to doxycycline within 24-72 hours. One of the three patients who required PICU support responded to intravenous chloramphenicol and, of the other two (6·6%), one died of acute respiratory distress syndrome and the other owing to acute renal failure. A high index of suspicion is essential for early diagnosis and prevention of complications in scrub typhus together with prompt referral from rural areas to a higher centre. Awareness of the disease manifestations may further help to prevent excessive investigations in patients presenting with non-specific febrile illness and reduce the economic burden to the family and society in resource-constrained settings.
Scrub typhus in rural Rajasthan and a review of other Indian studies.
Masand, Rupesh; Yadav, Ritesh; Purohit, Alok; Tomar, Balvir Singh
2016-01-09
Scrub typhus is an acute febrile illness which has been reported from various parts of India with Rajasthan recently joining the list of affected states. To report a series of paediatric scrub typhus cases from rural Rajasthan. Retrospective review of children with scrub typhus admitted to the wards and paediatric intensive care unit (PICU) of a tertiary-care hospital. The study was undertaken over an 8-month period from May to December 2013. All patients with a clinical presentation and/or serological confirmation of scrub typhus who tested negative for malaria, enteric fever, dengue, leptospirosis and urinary tract infection (UTI) were included. A range of investigations were undertaken including IgM-ELISA for scrub typhus, followed by appropriate medical management. Thirty patients satisfied the inclusion criteria. The mean (SD, range) age of the patients was 8·56 (3·43, 3-16) years. The most common clinical features were fever (n = 30, 100%), headache (n = 20, 66%), myalgia (n = 15, 50%), hepatosplenomegaly (n = 18, 60%) and pallor (n = 5, 16%). Typical features such as eschar and rash were observed in only one (3·3%) and three (10%) patients, respectively; none had generalised lymphadenopathy or conjunctival congestion. IgM-ELISA for scrub typhus was positive in 28 patients (93·3%) and 27 responded to doxycycline within 24-72 hours. One of the three patients who required PICU support responded to intravenous chloramphenicol and, of the other two (6·6%), one died of acute respiratory distress syndrome and the other owing to acute renal failure. A high index of suspicion is essential for early diagnosis and prevention of complications in scrub typhus together with prompt referral from rural areas to a higher centre. Awareness of the disease manifestations may further help to prevent excessive investigations in patients presenting with non-specific febrile illness and reduce the economic burden to the family and society in resource-constrained settings.
A Systematic Review of Mortality from Untreated Scrub Typhus (Orientia tsutsugamushi).
Taylor, Andrew J; Paris, Daniel H; Newton, Paul N
2015-01-01
Scrub typhus, a bacterial infection caused by Orientia tsutsugamushi, is increasingly recognized as an important cause of fever in Asia, with an estimated one million infections occurring each year. Limited access to health care and the disease's non-specific symptoms mean that many patients are undiagnosed and untreated, but the mortality from untreated scrub typhus is unknown. This review systematically summarizes the literature on the untreated mortality from scrub typhus and disease outcomes. A literature search was performed to identify patient series containing untreated patients. Patients were included if they were symptomatic and had a clinical or laboratory diagnosis of scrub typhus and excluded if they were treated with antibiotics. The primary outcome was mortality from untreated scrub typhus and secondary outcomes were total days of fever, clinical symptoms, and laboratory results. A total of 76 studies containing 89 patient series and 19,644 patients were included in the final analysis. The median mortality of all patient series was 6.0% with a wide range (min-max) of 0-70%. Many studies used clinical diagnosis alone and had incomplete data on secondary outcomes. Mortality varied by location and increased with age and in patients with myocarditis, delirium, pneumonitis, or signs of hemorrhage, but not according to sex or the presence of an eschar or meningitis. Duration of fever was shown to be long (median 14.4 days Range (9-19)). Results show that the untreated mortality from scrub typhus appears lower than previously reported estimates. More data are required to clarify mortality according to location and host factors, clinical syndromes including myocarditis and central nervous system disease, and in vulnerable mother-child populations. Increased surveillance and improved access to diagnostic tests are required to accurately estimate the untreated mortality of scrub typhus. This information would facilitate reliable quantification of DALYs and guide empirical treatment strategies.
Payne, Kevin S; Klein, Terry A; Otto, Jean L; Kim, Heung-Chul; Chong, Sung-Tae; Ha, Si Jung; Gu, Se Hun; Jeong, Ji Hae; Baek, Luck Ju; Song, Jin-Won
2009-10-01
This study sought to identify seasonal and environmental determinants of scrub typhus, murine typhus, and leptospirosis in small mammals trapped at Dagmar North training area, Gyeonggi Province, South Korea. Small mammals received titer assays to the aforementioned diseases. Logistic regression analyses were conducted to determine whether associations existed between risk of small-mammal infection and independent variables such as season of capture, habitat, small-mammal species, and sex. Murine typhus was not detected among the animals assayed. Risk of scrub typhus infection was associated with season, habitat, and small-mammal species. Risk of leptospirosis infection was associated with season and habitat. These findings indicate determinants of infection exist for scrub typhus and leptospirosis at this training site. This information can be used for developing appropriate preventive medicine plans and coordinating troop activity during periods of reduced exposure decreasing the likelihood of disease transmission to humans.
Entomology with the U.S. Marines in Vietnam - Some Lessons Learned
2008-11-16
these areas, and capability of individual commands. malaria, dengue, encephalitis, plague, This included the provision of scrub typhus and filariasis...any, probably due to the large, mobile was not available at the time. About 22 parasite reservoir (NVA, VC & local cases of scrub typhus occurred in...of light traps was November in Danang. often a challenge. Their use in the Filariasis, Scrub Typhus & Plague. "bush" was not feasible for security
Clinical manifestations of scrub typhus.
Rajapakse, Senaka; Weeratunga, Praveen; Sivayoganathan, Sriharan; Fernando, Sumadhya Deepika
2017-02-01
The mite-borne rickettsial zoonosis scrub typhus is widely prevalent in parts of Southeast and Far East Asia, and northern Australia. The disease is an acute febrile illness, associated with rash and often an eschar, which responds dramatically to treatment with antibiotics. In some cases it results in a serious illness leading to multiple organ involvement and death. The disease manifestations are thought to result from a systemic vasculitis, caused by both direct effects of the organisms as well as an exaggerated immune response, although little is understood about its pathogenesis. A wide spectrum of clinical manifestations, affecting nearly every organ system, have been described with scrub typhus. Some of these manifestations are serious and life threatening. In this systematic review, we summarise the typical and atypical manifestations of scrub typhus reported in the literature. Awareness of these unusual manifestations will hopefully guide clinicians towards diagnosing the condition early, and initiating early appropriate antibiotics and other supportive measures. © The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Urbanization of Scrub Typhus Disease in South Korea
Park, Sang-Won; Ha, Na-Young; Ryu, Boyeong; Bang, Ji Hwan; Song, Hoyeon; Kim, Yuri; Kim, Gwanghun; Oh, Myoung-don; Cho, Nam-Hyuk; Lee, Jong-koo
2015-01-01
Background Scrub typhus is an endemic disease in Asia. It has been a rural disease, but indigenous urban cases have been observed in Seoul, South Korea. Urban scrub typhus may have a significant impact because of the large population. Methods Indigenous urban scrub typhus was epidemiologically identified in Seoul, the largest metropolitan city in South Korea, using national notifiable disease data from 2010 to 2013. For detailed analysis of clinical features, patients from one hospital that reported the majority of cases were selected and compared to a historic control group. Chigger mites were prospectively collected in the city using a direct chigger mite-collecting trap, and identified using both phenotypic and 18S rDNA sequencing analyses. Their infection with Orientia tsutsugamushi was confirmed by sequencing the 56-kDa antigen gene. Results Eighty-eight cases of urban scrub typhus were determined in Seoul. The possible sites of infection were mountainous areas (56.8%), city parks (20.5%), the vicinity of one’s own residence (17.0%), and riversides (5.7%). Eighty-seven chigger mites were collected in Gwanak mountain, one of the suspected infection sites in southern Seoul, and seventy-six (87.4%) of them were identified as Helenicula miyagawai and eight (9.2%) as Leptotrombidium scutellare. Pooled DNA extracted from H. miyagawai mites yielded O. tsutsugamushi Boryong strain. Twenty-six patients from one hospital showed low APACHE II score (3.4 ± 2.7), low complication rate (3.8%), and no hypokalemia. Conclusions We identified the presence of indigenous urban scrub typhus in Seoul, and a subgroup of them had mild clinical features. The chigger mite H. miyagawai infected with O. tsutsugamushi within the city was found. In endemic area, urban scrub typhus needs to be considered as one of the differential febrile diseases and a target for prevention. PMID:26000454
Anitharaj, Velmurugan; Stephen, Selvaraj; Pradeep, Jothimani; Park, Sungman; Kim, Seung-Han; Kim, Young Jin; Kim, Eun-Ye; Kim, Yoon-Won
2016-11-01
Scrub Typhus (ST) is being reported from different parts of India in the recent past. However, the diagnosis and confirmation of ST cases require specific serological and molecular diagnostic tests. Both rapid and conventional ELISA tests need to be properly evaluated. Evaluation of a new ST IgM Immunochromatography (ICT) test kit (InBios Scrub Typhus Detect IgM Rapid Test) and compare it with another rapid kit, conventional ELISA kit and Weil-Felix (WF) test. This prospective study was carried out in Mahatma Gandhi Medical College and Research Institute, Puducherry, during November 2015 to June 2016. Clinically suspected 220 ST patients were examined by a new kit, InBios Scrub Typhus Detect IgM Rapid Test, taking the conventional InBios Scrub Typhus Detect IgM ELISA as reference. Additional comparison was made with ImmuneMed Scrub Typhus Rapid, and WF test (single OXK titers ≥1:320). Statistical analysis was performed (Chi-square, Spearman's correlation and Kappa) using IBM SPSS Statistics 17 for Windows (SPSS Inc; Chicago, USA). Percentage Sensitivity, Specificity, Positive Predictive and Negative Predictive Values for InBios, ImmuneMed and WF were 99.25, 93.02, 95.68, 98.77; 94.87, 94.19, 96.21, 92.05 and 50.38, 95.51, 94.29, 56.67 respectively. A total of 134 patients were positive in reference standard InBios IgM ELISA. This new rapid ST IgM kit validated for the first time in India, showed good sensitivity and specificity. As a Point-of-Care (PoC) test, the kit would be helpful in both urban and remote rural parts of India.
Anitharaj, Velmurugan; Pradeep, Jothimani; Park, Sungman; Kim, Seung-Han; Kim, Young Jin; Kim, Eun-Ye; Kim, Yoon-Won
2016-01-01
Introduction Scrub Typhus (ST) is being reported from different parts of India in the recent past. However, the diagnosis and confirmation of ST cases require specific serological and molecular diagnostic tests. Both rapid and conventional ELISA tests need to be properly evaluated. Aim Evaluation of a new ST IgM Immunochromatography (ICT) test kit (InBios Scrub Typhus Detect IgM Rapid Test) and compare it with another rapid kit, conventional ELISA kit and Weil-Felix (WF) test. Materials and Methods This prospective study was carried out in Mahatma Gandhi Medical College and Research Institute, Puducherry, during November 2015 to June 2016. Clinically suspected 220 ST patients were examined by a new kit, InBios Scrub Typhus Detect IgM Rapid Test, taking the conventional InBios Scrub Typhus Detect IgM ELISA as reference. Additional comparison was made with ImmuneMed Scrub Typhus Rapid, and WF test (single OXK titers ≥1:320). Statistical analysis was performed (Chi-square, Spearman’s correlation and Kappa) using IBM SPSS Statistics 17 for Windows (SPSS Inc; Chicago, USA). Results Percentage Sensitivity, Specificity, Positive Predictive and Negative Predictive Values for InBios, ImmuneMed and WF were 99.25, 93.02, 95.68, 98.77; 94.87, 94.19, 96.21, 92.05 and 50.38, 95.51, 94.29, 56.67 respectively. A total of 134 patients were positive in reference standard InBios IgM ELISA. Conclusion This new rapid ST IgM kit validated for the first time in India, showed good sensitivity and specificity. As a Point-of-Care (PoC) test, the kit would be helpful in both urban and remote rural parts of India. PMID:28050364
Urbanization of scrub typhus disease in South Korea.
Park, Sang-Won; Ha, Na-Young; Ryu, Boyeong; Bang, Ji Hwan; Song, Hoyeon; Kim, Yuri; Kim, Gwanghun; Oh, Myoung-don; Cho, Nam-Hyuk; Lee, Jong-koo
2015-05-01
Scrub typhus is an endemic disease in Asia. It has been a rural disease, but indigenous urban cases have been observed in Seoul, South Korea. Urban scrub typhus may have a significant impact because of the large population. Indigenous urban scrub typhus was epidemiologically identified in Seoul, the largest metropolitan city in South Korea, using national notifiable disease data from 2010 to 2013. For detailed analysis of clinical features, patients from one hospital that reported the majority of cases were selected and compared to a historic control group. Chigger mites were prospectively collected in the city using a direct chigger mite-collecting trap, and identified using both phenotypic and 18S rDNA sequencing analyses. Their infection with Orientia tsutsugamushi was confirmed by sequencing the 56-kDa antigen gene. Eighty-eight cases of urban scrub typhus were determined in Seoul. The possible sites of infection were mountainous areas (56.8%), city parks (20.5%), the vicinity of one's own residence (17.0%), and riversides (5.7%). Eighty-seven chigger mites were collected in Gwanak mountain, one of the suspected infection sites in southern Seoul, and seventy-six (87.4%) of them were identified as Helenicula miyagawai and eight (9.2%) as Leptotrombidium scutellare. Pooled DNA extracted from H. miyagawai mites yielded O. tsutsugamushi Boryong strain. Twenty-six patients from one hospital showed low APACHE II score (3.4 ± 2.7), low complication rate (3.8%), and no hypokalemia. We identified the presence of indigenous urban scrub typhus in Seoul, and a subgroup of them had mild clinical features. The chigger mite H. miyagawai infected with O. tsutsugamushi within the city was found. In endemic area, urban scrub typhus needs to be considered as one of the differential febrile diseases and a target for prevention.
Bhargava, Anurag; Kaushik, Reshma; Kaushik, Rajeev Mohan; Sharma, Anita; Ahmad, Sohaib; Dhar, Minakshi; Mittal, Garima; Khanduri, Sushant; Pant, Priyannk; Kakkar, Rajesh
2016-12-01
Scrub typhus is a re-emerging mite-borne rickettsiosis, which continues to be underdiagnosed, with lethal consequences. The present study was conducted to determine the seasonality, clinical presentation and predictors of mortality in patients with scrub typhus at a tertiary care teaching hospital in northern India. Scrub typhus was suspected in patients attending the hospital as per the standard case definition and serological evidence was obtained by performing an IgM ELISA. A total of 284 patients with scrub typhus from urban and rural areas were seen, predominantly from July to November. The most common clinical presentation was a bilateral community-acquired pneumonia (CAP), which resembled pneumonia due to atypical pathogens and often progressed to acute respiratory distress syndrome (ARDS). An acute undifferentiated febrile illness (AUFI) or a febrile illness associated with altered sensorium, aseptic meningitis, shock, abdominal pain, gastrointestinal bleeding or jaundice was also seen. Eschars were seen in 17 per cent of patients, and thrombocytopenia, transaminitis and azotaemia were frequent. There were 24 deaths (8.5%) caused predominantly by ARDS and multi-organ dysfunction. The mortality in patients with ARDS was high (37%). ARDS [odds ratio (OR)=38.29, 95% confidence interval (CI): 9.93, 147.71] and acute kidney injury (OR=8.30, 95% CI: 2.21, 31.21) were the major predictors of death. The present findings indicate that scrub typhus may be considered a cause of CAP, ARDS, AUFI or a febrile illness with multisystem involvement, in Uttarakhand and Uttar Pradesh, especially from July to November. Empiric therapy of CAP may include doxycycline or azithromycin to ensure coverage of underlying unsuspected scrub typhus.
Leptospirosis Scrub Typhus and Colorado Tick Fever Like Disease in Korea
1991-01-24
leptospirosis in humanm, serological surveys will also be done in bovine and swine populations to assess the distribution, serotypes and prevalence of...34AD-A2 35 000 AD______ GRANT NO: DAND17-88-Z-8042 TITLE: LEPTOSPIROSIS , SCRUB TYPHUS AND COLORADO TICK FEVER LIKE DISEASE IN KOREA PRINCIPAL...21702-5012 63807A 63807D809 AN A315678 11. TITLE (Inc•ude Security Classfication) LEPTOSPIROSIS , SCRUB TYPHUS AND COLORADO TICK FEVER LIKE DISEASE IN
Paris, D H; Jenjaroen, K; Blacksell, S D; Phetsouvanh, R; Wuthiekanun, V; Newton, P N; Day, N P J; Turner, G D H
2008-01-01
Scrub typhus is responsible for a large proportion of undifferentiated fevers in south-east Asia. The cellular tropism and pathophysiology of the causative agent, Orientia tsutsugamushi, remain poorly understood. We measured endothelial and leucocyte activation by soluble cell adhesion molecule enzyme-linked immunosorbent assays in 242 Lao and Thai patients with scrub or murine typhus, leptospirosis, dengue, typhoid and uncomplicated falciparum malaria on admission to hospital. Soluble E-selectin (sE-selectin) levels were lowest in dengue, sL-selectin highest in scrub typhus with a high sE-selectin to sL-selectin ratio in leptospirosis patients. In scrub typhus patients elevated sL-selectin levels correlated with the duration of skin rash (P = 0·03) and the presence of eschar (P = 0·03), elevated white blood cell (WBC) count (P = 0·007), elevated lymphocyte (P = 0·007) and neutrophil counts (P = 0·015) and elevated levels of sE-selectin correlated with the duration of illness before admission (P = 0·03), the presence of lymphadenopathy (P = 0·033) and eschar (P = 0·03), elevated WBC (P = 0·005) and neutrophil counts (P = 0·0003). In comparison, soluble selectin levels in murine typhus patients correlated only with elevated WBC counts (P = 0·03 for sE-selectin and sL-selectin). Soluble intercellular adhesion molecule-1 and soluble vascular adhesion molecule-1 levels were not associated significantly with any clinical parameters in scrub or murine typhus patients. The data presented suggest mononuclear cell activation in scrub typhus. As adhesion molecules direct leucocyte migration and induce inflammatory and immune responses, this may represent O. tsutsugamushi tropism during early dissemination, or local immune activation within the eschar. PMID:18505434
Paris, D H; Jenjaroen, K; Blacksell, S D; Phetsouvanh, R; Wuthiekanun, V; Newton, P N; Day, N P J; Turner, G D H
2008-07-01
Scrub typhus is responsible for a large proportion of undifferentiated fevers in south-east Asia. The cellular tropism and pathophysiology of the causative agent, Orientia tsutsugamushi, remain poorly understood. We measured endothelial and leucocyte activation by soluble cell adhesion molecule enzyme-linked immunosorbent assays in 242 Lao and Thai patients with scrub or murine typhus, leptospirosis, dengue, typhoid and uncomplicated falciparum malaria on admission to hospital. Soluble E-selectin (sE-selectin) levels were lowest in dengue, sL-selectin highest in scrub typhus with a high sE-selectin to sL-selectin ratio in leptospirosis patients. In scrub typhus patients elevated sL-selectin levels correlated with the duration of skin rash (P = 0.03) and the presence of eschar (P = 0.03), elevated white blood cell (WBC) count (P = 0.007), elevated lymphocyte (P = 0.007) and neutrophil counts (P = 0.015) and elevated levels of sE-selectin correlated with the duration of illness before admission (P = 0.03), the presence of lymphadenopathy (P = 0.033) and eschar (P = 0.03), elevated WBC (P = 0.005) and neutrophil counts (P = 0.0003). In comparison, soluble selectin levels in murine typhus patients correlated only with elevated WBC counts (P = 0.03 for sE-selectin and sL-selectin). Soluble intercellular adhesion molecule-1 and soluble vascular adhesion molecule-1 levels were not associated significantly with any clinical parameters in scrub or murine typhus patients. The data presented suggest mononuclear cell activation in scrub typhus. As adhesion molecules direct leucocyte migration and induce inflammatory and immune responses, this may represent O. tsutsugamushi tropism during early dissemination, or local immune activation within the eschar.
Sharma, S R; Masaraf, H; Lynrah, K G; Lyngdoh, M
2015-01-01
Scrub typhus is rampant in northern, eastern, and southern India. Central nervous system involvement in the form of meningitis or meningoencephalitis is common in scrub typhus. As specific laboratory methods remain inadequate or inaccessible in developing countries, prompt diagnosis is often difficult. The aim of this study was to characterize neurological complications in scrub typhus from northeastern region of India. We did a prospective study of scrub meningoencephalitis at North Eastern Indira Gandhi Regional Institute of Medical Sciences among patients admitted to hospital between October 2009 and November 2011. The diagnosis was made based on the clinical pictures, presence of an eschar, and a positive Weil-Felix test (WFT) with a titer of >1:160 and if required a positive scrub IgM enzyme-linked immunosorbent assay. Lumbar puncture was performed in patients with headache, nuchal rigidity, altered sensorium or cranial nerve deficits, and magnetic resonance imaging (MRI) brain performed if needed. Twenty-three patients of scrub typhus meningitis that were serologically confirmed were included in the study. There were 13 males and 10 females. Fever ≥1 week was the most common manifestation (39.1%). Interestingly, none had an eschar. Median cerebrospinal fluid (CSF) cell count, lymphocyte percentage, CSF protein, CSF glucose/blood glucose, CSF ADA were 17 cells/μL, 90%, 86 mg/dL, 0.6605 and 3.6 U/mL, respectively. All patients were treated with doxycycline. There was no mortality in our study. Absence of Eschar does not rule out scrub typhus. Clinical features and CSF findings can mimic tuberculous meningitis so misdiagnosis may lead to unwarranted prolonged empirical antituberculous therapy in cases of lymphocytic meningoencephalitis. Delay in treatment can be potentially fatal. WFT still serves as a useful and affordable diagnostic tool for this disease in resource-poor countries.
Janardhanan, Jeshina; Joseph Martin, Sherry; Astrup, Elisabeth; Veeramanikandan, R; Aukrust, Pål; Abraham, Ooriapadickal C; Varghese, George M
2013-11-01
Scrub typhus is a highly prevalent bacterial infection in India and South Asia that is caused by Orientia tsutsugamushi. The innate immune response to infections is modulated by Toll-like receptors (TLRs) and heat shock proteins (HSPs). This study was done to assess the prevalence and possible association of TLR and HSP polymorphisms in scrub typhus. TLR4 Asp299Gly, TLR4 Thr399Ile, TLR2 Arg753Gln and HSP70-2 A1267G are single-nucleotide polymorphisms (SNPs) that may modulate their activities, and these SNPs were assessed in 137 scrub typhus patients and 134 controls by PCR restriction fragment length polymorphism. We found that the two TLR4 mutations, TLR4 D299G and TLR4T399I, were present in 19.5% and 22% of the study population, respectively, and was in significant linkage disequilibrium with a D' of 0.8. The TLR2 mutation was found to be rare, whereas the HSP A>G mutation was very common (77.5%). Compared with the controls, the prevalence of heterozygous genotype of the TLR4D299G SNP, but not any of the other SNPs, was significantly higher among scrub typhus patients. Further studies using a larger sample size and more candidate genes may better enable in determining the role of these associations in susceptibility and severity of scrub typhus.
Guillan-Barré syndrome following scrub typus: two case reports.
Sakai, Katsuya; Ishii, Nobuyuki; Ebihara, Yuka; Mochizuki, Hitoshi; Shiomi, Kazutaka; Nakazato, Masamitsu
2016-08-31
Case 1: A 66-year-old man was admitted because of progressive gait disturbance and dysphagia after developing red rash. He was diagnosed as Guillain-Barré syndrome (GBS) and treated by intravenous immunoglobulin therapy (IVIg). Two weeks later, he could swallow and walk without any abnormalities. Case 2: A 58-year-old woman was admitted because of gait disturbance, bilateral peripheral facial nerve palsies, and respiratory failure one week after developing fever and rash. She was diagnosed as GBS and treated with IVIg. She underwent mechanical ventilation, while she could wean off it one month later and her limb strengths improved. We confirmed both patients had scrub typhus by serological studies. Peripheral neuropathy is one of the complications of scrub typhus. In addition, this disease sometimes leads to severe GBS. GBS should be included in differential diagnosis when peripheral neuropathies develop in the course of treating scrub typhus, and we should keep in mind that scrub typhus is one of the causes of GBS.
Scrub typhus: audit of an outbreak.
Krishna, Mani Ram; Vasuki, B; Nagaraju, K
2015-06-01
To document the epidemiological, clinical and laboratory profile of all children with scrub typhus at a tertiary care centre in Chennai between September 2010 and June 2011. The case records of all children admitted and diagnosed with scrub typhus between September 2010 and June 2011 were analysed to look for salient clinical and laboratory parameters. During the study period, 52 children were admitted with scrub typhus in the authors' hospital. The presenting complaints included fever in all cases. Other symptoms included swelling of legs (50 %) and vomiting (45 %). 13 % presented with CNS symptoms. The commonest physical findings included eschar (67 %), hepatomegaly (94 %), splenomegaly (73 %) and third spacing (67 %). Salient lab parameters included packed cell volume (PCV) <30 (48 %), leucocytosis (56 %), positive C-reactive protein (CRP) (92 %), hypoalbuminemia (79 %). Common complications included acute kidney injury (10 %) and peripheral gangrene (4 %). There was no mortality in the present case series. The clinical profile of children with scrub typhus in a tertiary care centre is reported. Eschar and hepatosplenomegaly with a high CRP value is helpful in diagnosis. All patients responded well to the treatment.
Prevalence and risk factors for scrub typhus in South India.
Trowbridge, Paul; P, Divya; Premkumar, Prasanna S; Varghese, George M
2017-05-01
To determine the prevalence and risk factors of scrub typhus in Tamil Nadu, South India. We performed a clustered seroprevalence study of the areas around Vellore. All participants completed a risk factor survey, with seropositive and seronegative participants acting as cases and controls, respectively, in a risk factor analysis. After univariate analysis, variables found to be significant underwent multivariate analysis. Of 721 people participating in this study, 31.8% tested seropositive. By univariate analysis, after accounting for clustering, having a house that was clustered with other houses, having a fewer rooms in a house, having fewer people living in a household, defecating outside, female sex, age >60 years, shorter height, lower weight, smaller body mass index and smaller mid-upper arm circumference were found to be significantly associated with seropositivity. After multivariate regression modelling, living in a house clustered with other houses, female sex and age >60 years were significantly associated with scrub typhus exposure. Overall, scrub typhus is much more common than previously thought. Previously described individual environmental and habitual risk factors seem to have less importance in South India, perhaps because of the overall scrub typhus-conducive nature of the environment in this region. © 2017 John Wiley & Sons Ltd.
Distribution of Eschar in Pediatric Scrub Typhus.
Rose, Winsley; Rajan, Roshni J; Punnen, Anu; Ghosh, Urmi
2016-10-01
Identifying an eschar in scrub typhus is useful for initiation of prompt and appropriate antibiotic therapy. The distribution of eschars in all children <15 years of age admitted with confirmed scrub typhus over a 5 year period is described. Of 431 children admitted with scrub typhus, eschars were present in 176 (40.8%) children with the following distribution: head, face and neck, 33 (19.1%); axillae, 37 (21%); chest and abdomen, 21 (11.9%); genitalia, inguinal region and buttocks, 58 (33%); back, 8 (4.5%); upper extremities, 13 (7.4%); and lower extremities, 5 (2.8%). The commonest sites of eschars were scrotum (27 of 106; 25.5%) and axillae (15 of 106; 14.2%) in males and axillae (22 of 70; 31.4%) and groin (16 of 70; 22.9%) in females. Eschars were seen within skin folds in 100 of 176 (56.8%) children. Children should be carefully examined for the presence of eschar especially in the skin folds of the genitalia, axillae and groin to make an early diagnosis of scrub typhus. © The Author [2016]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Diagnostic evaluation of rapid tests for scrub typhus in the Indian population is needed.
Shivalli, Siddharudha
2016-05-12
Owing to frequent outbreaks witnessed in different parts of the country in the recent past, scrub typhus is being described as a re-emerging infectious disease in India. Differentiating scrub typhus from other endemic diseases like malaria, leptospirosis, dengue fever, typhoid, etc. is difficult due to overlapping clinical features and a lower positivity for eschars in Asian populations. Hence, the diagnosis heavily relies on laboratory tests. Costs and the need of technical expertise limit the wide use of indirect immunoperoxidase or immunofluorescence assays, ELISA and PCR. The Weil-Felix test is the most commonly used and least expensive serological test, but lacks both sensitivity and specificity. Hence, the diagnosis of scrub typhus is often delayed or overlooked. With due consideration of the cost, rapidity, single test result and simplicity of interpretation, rapid diagnostic tests have come into vogue. However, evaluation of rapid diagnostic tests for scrub typhus in the Indian population is needed to justify or discourage their use. Research studies are needed to find the most suitable test in terms of the rapidity of the result, simplicity of the procedure, ease of interpretation and cost to be used in the Indian populace.
Chang, Ko; Lee, Nan-Yao; Ko, Wen-Chien; Lin, Wei-Ru; Chen, Yen-Hsu; Tsai, Jih-Jin; Chen, Tun-Chieh; Lin, Chun-Yu; Chang, Ya-Ting; Lu, Po-Liang
2017-06-22
The clinical manifestations of scrub typhus, murine typhus and acute Q fever in the elderly are not clear. We conducted a retrospective study to identify the characteristics of the elderly aged ≥65 years with a comparison group aged 18-64 years among patients with scrub typhus, murine typhus, or acute Q fever who were serologically confirmed at three hospitals in Taiwan during 2002-2011. Among 441 cases, including 187 cases of scrub typhus, 166 acute Q fever, and 88 murine typhus, 68 (15.4%) cases were elderly patients. The elderly had a higher severe complication rate (10.3% vs. 3.5%, p = 0.022), but did not have a significantly higher mortality rate (1.47% vs. 0.54%, p = 0.396). Compared with those without severe complications, we found the elderly (p = 0.022), dyspnea (p = 0.006), less relative bradycardia (p = 0.004), less febrile illness (p = 0.004), prolonged prothrombin time (PT) (p = 0.002), higher levels of initial C-reactive protein (p = 0.039), blood leukocyte counts (p = 0.01), and lower platelet counts (p = 0.012) are significantly associated with severe complications. Only prolonged prothrombin time was associated with severe complications in multivariate analysis (p = 0.018, CI 95% 0.01-0.66). Among clinical symptoms and laboratory data, multivariate analysis revealed chills was less frequently occurred in the elderly (p = 0.012, 95% confidence interval [CI]: 1.33-9.99). The elderly cases with scrub typhus, murine typhus, or acute Q fever would be more likely to have severe complications, for which prothrombin time prolongation is an important predictor for severe complications. Copyright © 2017. Published by Elsevier B.V.
Clinico - Laboratory Profile of Scrub Typhus - An Emerging Rickettsiosis in India.
Narayanasamy, Dinesh Kumar; Arunagirinathan, Arul Kumaran; Kumar, Revathi Krishna; Raghavendran, V D
2016-11-01
To study the clinical and laboratory profile of pediatric scrub typhus in rural south India. This is a descriptive study of the clinical and laboratory features of 117 children with IgM ELISA proven scrub typhus out of 448 children, who were admitted in the Pediatric ward of a tertiary care hospital, during the study period of November 2014 through March 2015. Fever was present in all 117 children, with mean duration of fever at admission as 9 d. Gastrointestinal tract was the most commonly affected system, seen in 51 % of children. Cough (82 %), myalgia (70 %), vomiting (68 %), headache (45 %) and pain abdomen (42 %) were the most common symptoms of scrub typhus. Hepatomegaly (70), splenomegaly (53 %), pallor (50 %) and eschar (41 %) were the common clinical findings in children with scrub typhus. Out of 49 children with eschar, 32 were associated with regional lymphadenopathy, which was commonly seen in axillary, neck and groin regions. Leucocytosis (50 %), anemia (56 %), increased SGOT / SGPT (47 %), thrombocytopenia (41 %), hypoalbuminemia (40 %) and hyponatremia (40 %) were the common lab features. Shock (46 %), myocarditis (24 %) and pneumonia (16 %) were the common complications seen in these children. This study showed that early treatment for scrub typhus results in a good outcome in terms of early recovery and nil mortality. Regional lymphadenopathy is a marker of hidden or developing eschar. Total count and differential count should be interpreted on the background of the duration of fever. Since IgM ELISA, which is diagnostic of scrub typhus may not be widely available, any febrile child coming from rural area with hepatosplenomegaly, pallor, eschar, generalised / regional lymphadenopathy, anemia, leucocytosis, thrombocytopenia and increased Aspartate transaminase (AST) /Alanine aminotransferase (ALT) should be started on empirical Doxycycline or Azithromycin in order to prevent life threatening complications secondary to delay in therapy.
Mitra, Shubhanker; Gautam, Ira; Jambugulam, Mohan; Abhilash, Kundavaram Paul Prabhakar; Jayaseeelan, Vishalakshi
2017-01-01
Dengue and scrub typhus share similar clinical and epidemiological features, and are difficult to differentiate at initial presentation. Many places are endemic to both these infections where they comprise the majority of acute undifferentiated febrile illnesses. We aimed to develop a score that can differentiate scrub typhus from dengue. In this cross-sectional study, 188 cases of scrub typhus and 201 cases of dengue infection who presented to the emergency department or medicine outpatient clinic from September 2012 to April 2013 were included. Univariate followed by multivariate logistic regression analysis was performed to identify clinical features and laboratory results that were significantly different between the two groups. Each variable was assigned scores based on the strength of association and receiver operating characteristics area under the curve (ROC-AUC) was generated and compared. Six scoring models were explored to ascertain the model with the best fit. Model 2 was developed using the following six variables: oxygen saturation (>90%, ≤90%), total white blood cell count (<4000, 4001-7000 and >7000 cells/cumm), hemoglobin (≤14 and >14 g/dL), total bilirubin (<2 and ≥2 mg/dL), serum glutamic oxaloacetic transaminase (>200 and ≥200 IU/dL), and altered sensorium (present or absent). Each variable was assigned scores based on its strength of association. The AUC-ROC curve (95% confidence interval) for model 2 was 0.84 (0.79-0.89). At the cut off score of 13, the sensitivity and specificity were 85% and 77% respectively, with a higher score favoring dengue. In areas of high burden of ST and dengue, model 2 (the "clinical score to differentiate scrub typhus and dengue fever") is a simple and rapid clinical scoring system that may be used to differentiate scrub typhus and dengue at initial presentation.
Giri, Prabahs Prasun; Roy, Joydeb; Saha, Agnisekhar
2018-02-01
Scrub typhus has been globally recognized as an emerging infectious disease contributing significantly to pyrexia of unknown origin (PUO) and a potential cause of multiorgan dysfunction syndrome (MODS). We studied the incidence of scrub typhus as a cause of pediatric intensive care unit (PICU) admission and MODS in our hospital and its clinical and laboratory characteristics to measure the incidence of MODS caused by scrub typhus. This study was done in a pediatric teaching hospital in Kolkata, India. Records of patients admitted with PUO from March 2012 to December 2015 were reviewed. Rathi-Goodman-Aghai scoring system was used to identify potential ST patients and confirmed by serological testing. Clinical characteristics, laboratory findings, and treatment response were noted of those needing PICU admissions. Ninety-seven cases of scrub typhus have been identified during that period. PICU admission was needed in 30 of them (31%) which contributed 8.43% of total PICU admissions. Among these 30 patients, 16 (53%) developed MODS which contributed 18.29% of total MODS admitted in PICU. Septic shock was the most common manifestation in as many as 18 (60%) patients followed by encephalopathy in 13 (43%). Patients were treated with either doxycycline alone or in combination with azithromycin. Mean time to complete defervescence was 32 h after first dose of doxycycline. The outcome was excellent without a single mortality. Scrub typhus is an important cause of MODS in this part of the world, especially in fevers associated with features as identified and not responding to conventional antibiotics.
Ahmad, S; Dhar, M; Mittal, G; Bhat, N K; Shirazi, N; Kalra, V; Sati, H C; Gupta, V
2016-04-01
Positive serology for dengue and/or scrub typhus infection with/without positive malarial smear (designated as mixed or co-infection) is being increasingly observed during epidemics of acute undifferentiated febrile illnesses (AUFIs). We planned to study the clinical and biochemical spectrum of co-infections with Plasmodium sp., dengue virus and scrub typhus and compare these with mono-infection by the same organisms. During the period from December 2012 to December 2013, all cases presenting with AUFIs to a single medical unit of a referral centre in Garhwal region of the north Indian state of Uttarakhand were retrospectively selected and categorised aetiologically as co-infections, malaria, dengue or scrub typhus. The groups thus created were compared in terms of demographic, clinical, biochemical and outcome parameters. The co-infection group (n = 49) was associated with milder clinical manifestations, fewer, milder and non-progressive organ dysfunction, and lesser need for intensive care, mechanical ventilation and dialysis as compared to mono-infections. When co-infections were sub-grouped and compared with the relevant mono-infections, there were differences in certain haematological and biochemical parameters; however, this difference did not translate into differential outcomes. Scrub typhus mono-infection was associated with severe disease in terms of both morbidity and mortality. Malaria, dengue and scrub typhus should be routinely tested in all patients with AUFIs. Co-infections, whether true or due to serological cross-reactivity, appear to be a separate entity so far as presentation and morbidity is concerned. Further insight is needed into the mechanism and identification of the protective infection.
Zhang, Luyan; Bi, Zhenwang; Kou, Zengqiang; Yang, Huili; Zhang, Aihua; Zhang, Shoufeng; Meng, Xiangpeng; Zheng, Li; Zhang, Meng; Yang, Hui; Zhao, Zhongtang
2015-03-01
Orientia tsutsugamushi, the causative agent of scrub typhus, is an obligate intracellular bacterium and characterized by dramatic genetic diversity. To elucidate the genotypes of O. tsutsugamushi populating in patients in Shandong Province, a new epidemic zone in China, we sequenced partial of the 56-kDa type-specific antigen gene (TSA) and identified the genotypes of 43 O. tsutsugamushi samples from human patients confirmed with scrub typhus from 2010 to 2013. All of the 43 sequences are in the same clade, 39 of them are in one branch and the other four sequences, nominated as SH1002, SH1306, SH1309, and SH1307 are in four separate branches. To clarify the clinical characterizations caused by Kawasaki-related genotypes, we studied the clinical profiles of these 43 scrub typhus patients. Most patients (88.1%) were farmers lived in rural areas. They presented with fever (100.0%), headache (79.1%), dizziness (32.6%), generalized myalgia (48.8%), fatigue (53.5%), anorexia (53.5%), facial flushing (23.3%), conjunctival congestion (11.6%), skin rashes (58.1%) and lymphadenopathy (23.3%). Eschar (97.7%) was quite common in patients, which provided doctors with a luminous clue for diagnosis of scrub typhus. Thrombocytopenia was seen in 23.1% of patients, and three patients (7.0%) had bronchopneumonia. There was no death report in Shandong Province during the study period. The present study provides beneficial data for clinical, serological, and molecular diagnosis of scrub typhus infections, and also provides foundations for subsequent studies. Copyright © 2015 Elsevier B.V. All rights reserved.
Molecular detection of Orientia tsutsugamushi from suspected scrub typhus cases.
Srinivasan, Seethalakshmi; Menon, Thangam
2017-01-01
Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi. The disease is under-diagnosed in India, because of low index of suspicion and also due to its nonspecific presentation, and lack of confirmatory diagnostic tests. This study was undertaken to diagnose scrub typhus in patients with undifferentiated fevers by serology and molecular methods. A total of 68 blood samples were collected from patients clinically suspected to have scrub typhus. After transportation to the laboratory, the serum was separated from the blood and subjected to rapid card test. The ethylenediaminetetraacetic acid blood samples were subjected to DNA extraction using QIAamp DNA Mini Kit followed by nested polymerase chain reaction (nPCR). 24/68 (35.29%) cases showed the presence of antibody against scrub typhus by serology. 6/68 (8.8%) patients showed the presence of outer membrane protein antigen gene 56 kDa by nPCR. 5/24 serology positive cases showed the presence of 56 kDa outer membrane protein antigen gene by nPCR. A large number of cases positive by serology were negative by PCR which may indicate a low sensitivity of this test either due to low copy numbers or due to excess host DNA. Delay in treatment may increase disease severity and leads to higher mortality. Thus, molecular methods of diagnosis may aid in the early diagnosis of infection and enable prompt treatment. This is the first report on the diagnosis of scrub typhus in the suburbs of Chennai using molecular methods and reemphasizes the need for increased awareness of rickettsial infections in rural areas.
Scrub typhus cases in a teaching hospital in Penghu, Taiwan, 2006-2010.
Wang, Ying-Chuan; Chen, Po-Chuan; Lee, Kwai-Fong; Wu, Yu-Cheng; Chiu, Chun-Hsiang
2013-03-01
Scrub typhus is a mite-borne infectious disease caused by Orientia tsutsugamushi (previously called Rickettsia tsutsugamushi). The severity of this disease varies from only mild symptoms to death, and its manifestations are nonspecific. Therefore, clinicians may not correctly diagnose scrub typhus early enough for successful treatment. Reports of infections in travelers returning from Asia to their home countries are increasingly common. Thus, it is important that even clinicians in nonepidemic regions be alert for this disease. Here we describe the epidemiological aspects and clinical manifestations of scrub typhus encountered at a teaching hospital in Penghu, Taiwan, over the past 5 years. A total of 126 patients were confirmed to be positive for scrub typhus at the hospital from 2006 to 2010. All cases were confirmed by the Centers for Disease Control and Prevention or its contract laboratory through pathogen isolation and an indirect immunofluorescence assay. Medical records of these patients were reviewed, and demographic and clinical characteristics, laboratory data, seasonal data, geographic distribution, complications, and outcome were analyzed. The incidence of scrub typhus peaked in individuals aged 0-10 and 51-60 years, with the highest incidence among those ≤10 years of age. No significant difference was noted between sexes. Fever was the most common symptom (93.6%), followed by chills (23.8%), cough (18.3%), and headache (14.3%). Eschars were observed in 78 (61.9%) patients, with the axilla being the most frequent site (n=17; 21.8%). Most patients were retirees (n=63; 50%), followed by students (n=16; 12.7%). Patients were more likely to live in rural areas than urban areas. Scrub typhus was epidemic in the spring (April to June) and fall (October to December) in a bimodal distribution similar to that observed in Japan. Leukocytosis was not common, but most patients had abnormal C-reactive protein levels, thrombocytopenia, and elevated liver function test results. Residents of Penghu, particularly Makung City and Husi Township, as well as travelers to the region during the spring and fall seasons should be educated about the signs and symptoms of scrub typhus. All physicians who come into contact with individuals residing in or traveling to or from epidemic regions should remain alert about the manifestations of this disease.
Rickettsial Illnesses as Important Causes of Febrile Illness in Chittagong, Bangladesh
Kingston, Hugh W.; Hossain, Mosharraf; Leopold, Stije; Anantatat, Tippawan; Tanganuchitcharnchai, Ampai; Sinha, Ipsita; Plewes, Katherine; Maude, Richard J.; Chowdhury, M.A. Hassan; Paul, Sujat; Uddin, Rabiul Alam Mohammed Erfan; Siddiqui, Mohammed Abu Naser; Zahed, Abu Shahed; Abu Sayeed, Abdullah; Rahman, Mohammed Habibur; Barua, Anupam; Uddin, Mohammed Jasim; Sattar, Mohammed Abdus; Dondorp, Arjen M.; Blacksell, Stuart D.; Day, Nicholas P.J.; Ghose, Aniruddha; Hossain, Amir
2018-01-01
We conducted a yearlong prospective study of febrile patients admitted to a tertiary referral hospital in Chittagong, Bangladesh, to assess the proportion of patients with rickettsial illnesses and identify the causative pathogens, strain genotypes, and associated seasonality patterns. We diagnosed scrub typhus in 16.8% (70/416) and murine typhus in 5.8% (24/416) of patients; 2 patients had infections attributable to undifferentiated Rickettsia spp. and 2 had DNA sequence–confirmed R. felis infection. Orientia tsutsugamushi genotypes included Karp, Gilliam, Kato, and TA763-like strains, with a prominence of Karp-like strains. Scrub typhus admissions peaked in a biphasic pattern before and after the rainy season, whereas murine typhus more frequently occurred before the rainy season. Death occurred in 4% (18/416) of cases; case-fatality rates were 4% each for scrub typhus (3/70) and murine typhus (1/28). Overall, 23.1% (96/416) of patients had evidence of treatable rickettsial illnesses, providing important evidence toward optimizing empirical treatment strategies. PMID:29553921
Genotype Diversity and Distribution of Orientia tsutsugamushi Causing Scrub Typhus in Thailand
2011-07-01
typhus assay and vaccine development. Orientia tsutsugamushi, formerly known as Rickettsia tsutsug- amushi, is the causative agent of scrub typhus, a...Sunderland, MA. 13. Horinoucbi, H., et al. 1996. Genotypic identification of Rickettsia tsutsuga- mushi by restriction fragment length polymorphism... Rickettsia tsutsu· gamushi. Sequence and comparative analyses of the genes encoding TSA homologues from four antigenic variants. J. Bioi. Chern. 267:12728
Q Fever, Scrub Typhus, and Rickettsial Diseases in Children, Kenya, 2011-2012.
Maina, Alice N; Farris, Christina M; Odhiambo, Antony; Jiang, Ju; Laktabai, Jeremiah; Armstrong, Janice; Holland, Thomas; Richards, Allen L; O'Meara, Wendy P
2016-05-01
To increase knowledge of undifferentiated fevers in Kenya, we tested paired serum samples from febrile children in western Kenya for antibodies against pathogens increasingly recognized to cause febrile illness in Africa. Of patients assessed, 8.9%, 22.4%, 1.1%, and 3.6% had enhanced seroreactivity to Coxiella burnetii, spotted fever group rickettsiae, typhus group rickettsiae, and scrub typhus group orientiae, respectively.
Scrub typhus causing neonatal hepatitis with acute liver failure-A case series.
Vajpayee, Shailja; Gupta, R K; Gupta, M L
2017-05-01
Neonatal hepatitis with acute liver failure due to varied etiology including various infections is reported in the past. Scrub typhus as a cause of neonatal hepatitis has rarely been reported in literature. A high index of clinical suspicion is required for early diagnosis and timely treatment. Severity and prognosis of the disease varies widely because several different strains of Orientia tsutsugamushi exist with different virulence. Delayed diagnosis can result in complication and significant morbidity and mortality. Here, we report three cases of neonatal hepatitis with acute liver failure caused by scrub typhus to increase awareness.
Clinical significance of NGAL and KIM-1 for acute kidney injury in patients with scrub typhus.
Sun, In O; Shin, Sung Hye; Cho, A Young; Yoon, Hyun Ju; Chang, Mi Yok; Lee, Kwang Young
2017-01-01
The aim of this study is to investigate the clinical significance of neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) for acute kidney injury (AKI) in patients with scrub typhus. From 2014 to 2015, 145 patients were diagnosed with scrub typhus. Of these, we enrolled 138 patients who were followed up until renal recovery or for at least 3 months. We measured serum and urine NGAL and KIM-1 levels and evaluated prognostic factors affecting scrub typhus-associated AKI. Of the 138 patients, 25 had scrub typhus-associated AKI. The incidence of AKI was 18.1%; of which 11.6%, 4.3%, and 2.2% were classified as risk, injury, and failure, respectively, according to RIFLE criteria. Compared with patients in the non-AKI group, patients in the AKI group were older and showed higher total leukocyte counts and hypoalbuminemia or one or more comorbidities such as hypertension (72% vs 33%, p<0.01), diabetes (40% vs 14%, p<0.01), or chronic kidney disease (32% vs 1%, p<0.01). In addition, serum NGAL values (404± 269 vs 116± 78 ng/mL, P<0.001), KIM-1 values (0.80± 0.52 vs 0.33± 0.68 ng/mL, P<0.001), urine NGAL/creatinine values (371± 672 vs 27± 39 ng/mg, P<0.001) and urine KIM-1/creatinine values (4.04± 2.43 vs 2.38± 1.89 ng/mg, P<0.001) were higher in the AKI group than in the non-AKI group. By multivariate logistic regression, serum NGAL and the presence of chronic kidney disease were significant predictors of AKI. Serum NGAL might be an additive predictor for scrub typhus-associated AKI.
Ittyachen, Abraham M; Abraham, Saramma P; Krishnamoorthy, Smitha; Vijayan, Anuroopa; Kokkat, Jayamohan
2017-10-06
Scrub typhus is an acute infectious illness caused by Orientia tsutsugamushi. It is endemic to a part of the world known as the "tsutsugamushi triangle". Humans are accidental hosts in this zoonotic disease. About a third of patients admitted with scrub typhus have evidence of multi-organ dysfunction. Multi-organ dysfunction secondary to scrub typhus carries a high mortality rate. We report a 65-year old lady who was admitted in a Tertiary Care Center in the state of Kerala in India, with 7 day history of fever, myalgia and reduced urine output. Head to foot examination revealed the presence of an eschar on her chest. One week prior to the onset of her illness she had gone trekking through a hilly forest area. She was clinically suspected to have scrub typhus, which was later confirmed with laboratory tests. She developed multi-organ dysfunction syndrome secondary to this illness. Though there was an improvement in the multi-organ dysfunction, thrombocytopenia alone failed to improve. Bone marrow study was done which was suggestive of immune thrombocytopenia. Patient was given a course of steroids with which the thrombocytopenia improved. Failure of platelet count to normalize even after there has been a general improvement of other markers of multi-organ dysfunction in scrub typhus should prompt the clinician to consider other potential causes of thrombocytopenia. An unusual finding as this calls for further research to understand the molecular mechanisms behind such an event. Further, considering the close similarity in clinical presentation of several tropical illnesses, meticulous history taking and a detailed physical examination needs to be emphasized.
Sunyakumthorn, Piyanate; Somponpun, Suwit J.; Im-erbsin, Rawiwan; Anantatat, Tippawan; Jenjaroen, Kemajittra; Dunachie, Susanna J.; Lombardini, Eric D.; Burke, Robin L.; Blacksell, Stuart D.; Jones, James W.; Mason, Carl J.; Richards, Allen L.; Day, Nicholas P. J.
2018-01-01
Background Scrub typhus is an important endemic disease in tropical Asia caused by Orientia tsutsugamushi for which no effective broadly protective vaccine is available. The successful evaluation of vaccine candidates requires well-characterized animal models and a better understanding of the immune response against O. tsutsugamushi. While many animal species have been used to study host immunity and vaccine responses in scrub typhus, only limited data exists in non-human primate (NHP) models. Methodology/Principle findings In this study we evaluated a NHP scrub typhus disease model based on intradermal inoculation of O. tsutsugamushi Karp strain in rhesus macaques (n = 7). After an intradermal inoculation with 106 murine LD50 of O. tsutsugamushi at the anterior thigh (n = 4) or mock inoculum (n = 3), a series of time course investigations involving hematological, biochemical, molecular and immunological assays were performed, until day 28, when tissues were collected for pathology and immunohistochemistry. In all NHPs with O. tsutsugamushi inoculation, but not with mock inoculation, the development of a classic eschar with central necrosis, regional lymphadenopathy, and elevation of body temperature was observed on days 7–21 post inoculation (pi); bacteremia was detected by qPCR on days 6–18 pi; and alteration of liver enzyme function and increase of white blood cells on day 14 pi. Immune assays demonstrated raised serum levels of soluble cell adhesion molecules, anti-O. tsutsugamushi-specific antibody responses (IgM and IgG) and pathogen-specific cell-mediated immune responses in inoculated macaques. The qPCR assays detected O. tsutsugamushi in eschar, spleen, draining and non-draining lymph nodes, and immuno-double staining demonstrated intracellular O. tsutsugamushi in antigen presenting cells of eschars and lymph nodes. Conclusions/Significance These data show the potential of using rhesus macaques as a scrub typhus model, for evaluation of correlates of protection in both natural and vaccine induced immunity, and support the evaluation of future vaccine candidates against scrub typhus. PMID:29522521
Varghese, George M; Janardhanan, Jeshina; Mahajan, Sanjay K; Tariang, David; Trowbridge, Paul; Prakash, John A J; David, Thambu; Sathendra, Sowmya; Abraham, O C
2015-01-01
Scrub typhus, an acute febrile illness that is widespread in the Asia-Pacific region, is caused by the bacterium Orientia tsutsugamushi, which displays high levels of antigenic variation. We conducted an investigation to identify the circulating genotypes of O. tsutsugamushi in 3 scrub typhus-endemic geographic regions of India: South India, Northern India, and Northeast India. Eschar samples collected during September 2010-August 2012 from patients with scrub typhus were subjected to 56-kDa type-specific PCR and sequencing to identify their genotypes. Kato-like strains predominated (61.5%), especially in the South and Northeast, followed by Karp-like strains (27.7%) and Gilliam and Ikeda strains (2.3% each). Neimeng-65 genotype strains were also observed in the Northeast. Clarifying the genotypic diversity of O. tsutsugamushi in India enhances knowledge of the regional diversity among circulating strains and provides potential resources for future region-specific diagnostic studies and vaccine development.
Chang, Ko; Lee, Nan-Yao; Ko, Wen-Chien; Tsai, Jih-Jin; Lin, Wei-Ru; Chen, Tun-Chieh; Lu, Po-Liang; Chen, Yen-Hsu
2017-02-01
Dengue fever, rickettsial diseases, and Q fever are acute febrile illnesses with similar manifestations in tropical areas. Early differential diagnosis of scrub typhus, murine typhus, and Q fever from dengue fever may be made by understanding the distinguishing clinical characteristics and the significance of demographic and weather factors. We conducted a retrospective study to identify clinical, demographic, and meteorological characteristics of 454 dengue fever, 178 scrub typhus, 143 Q fever, and 81 murine typhus cases in three Taiwan hospitals. Case numbers of murine typhus and Q fever correlated significantly with temperature and rainfall; the scrub typhus case number was only significantly related with temperature. Neither temperature nor rainfall correlated with the case number of dengue fever. The rarity of dengue fever cases from January to June in Taiwan may be a helpful clue for diagnosis in the area. A male predominance was observed, as the male-to-female rate was 2.1 for murine typhus and 7.4 for Q fever. Multivariate analysis revealed the following six important factors for differentiating the rickettsial diseases and Q fever group from the dengue fever group: fever ≥8 days, alanine aminotransferase > aspartate aminotransferase, platelets >63,000/mL, C-reactive protein >31.9 mg/L, absence of bone pain, and absence of a bleeding syndrome. Understanding the rarity of dengue in the first half of a year in Taiwan and the six differentiating factors may help facilitate the early differential diagnosis of rickettsial diseases and Q fever from dengue fever, permitting early antibiotic treatment. Copyright © 2015. Published by Elsevier B.V.
Surveillance of potential hosts and vectors of scrub typhus in Taiwan.
Kuo, Chi-Chien; Lee, Pei-Lung; Chen, Chun-Hsung; Wang, Hsi-Chieh
2015-12-01
Scrub typhus is a lethal infectious disease vectored by larval trombiculid mites (i.e. chiggers) infected with Orientia tsutsugamushi (OT) and recent decades have witnessed an emergence of scrub typhus in several countries. Identification of chigger species and their vertebrate hosts is fundamental for the assessment of human risks to scrub typhus under environmental changes, but intensive and extensive survey of chiggers and their hosts is still lacking in Taiwan. Chiggers were collected from shrews and rodents in nine counties of Taiwan and were assayed for OT infections with nested polymerase chain reaction (PCR). PCR products were further sequenced to reveal probable OT strains. Rodents were assessed for OT exposure by immunofluorescent antibody assay. Lastly, incidence rate of scrub typhus in each county was associated with loads and prevalence of chigger infestations, seropositivity rate in rodents, and OT positivity rate in chiggers. Rattus losea was the most abundant (48.7% of 1,285 individuals) and widespread (occurred in nine counties) small mammal species and hosted the majority of chiggers (76.4% of 128,520 chiggers). Leptotrombidium deliense was the most common (64.9% of all identified chiggers) and widespread (occurred in seven counties) chigger species but was replaced by Leptotrombidium pallidum or Leptotrombidium scutellare during the cold seasons in two counties (Matsu and Kinmen) where winter temperatures were lower than other study sites. Seropositivity rate for OT exposure in 876 assayed rodents was 43.0% and OT positivity rate in 347 pools of chiggers was 55.9%, with 15 OT strains identified in the 107 successfully sequenced samples. Incidence rate of scrub typhus was positively correlated with chigger loads, prevalence of chigger infestations, seropositivity rate but not OT positivity rate in chiggers. Our study reveals R. losea as the primary host for chiggers and there exists a geographical and seasonal variation in chigger species in Taiwan. It also emphasizes the importance of recognition of chigger vectors and their vertebrate hosts for a better prediction of human risks to scrub typhus under rapid environmental changes.
Hemorrhagic Fever With Renal Syndrome (Korean Hemorrhagic Fever).
1992-04-30
serologically in 1990 and 1991 were 1,043 and 956, respectively and large outbreaks of scrub typhus, murine typhus, leptospirosis and spotted fever...and leptospirosis occured during epidemic season of HFRS in 1986 and nos. of confirmed patients serologically at our laboratory were 215 and 64, respn...ctive’ly. It ,"’s demonstrated that fieia mice and wild rats are reservoir hosts of HFRS, scrub typhus and leptospirosis in Korea. Global distribution
Jang, Mi-Ok; Jang, Hee-Chang; Kim, Uh Jin; Ahn, Joon Hwan; Kang, Seung-Ji; Jung, Sook-In; Shin, Hee-Young
2014-01-01
There are no well-matched, controlled studies comparing azithromycin with doxycycline for the treatment of complicated scrub typhus. A retrospective propensity score-matched case-control study was performed for patients who presented with complicated scrub typhus and were treated with doxycycline or azithromycin between 2001 and 2011. Data on comorbidities, clinical manifestations, laboratory studies, treatments, and outcomes were extracted for analysis. The clinical characteristics and outcomes of the azithromycin-treated group (n = 73) were compared to those of the doxycycline-treated group (n = 108). Of 181 patients, 73 from each group were matched by propensity scores. There were no significant differences in baseline characteristics between the matched groups. The treatment success and survival rates were not significantly different (89% [65/73 patients] versus 96% [70/73 patients] and 96% [70/73 patients] versus 96% [70/73 patients], respectively [P > 0.05]). No difference was observed in the time to defervescence or length of hospital stay between the two groups (P > 0.05). In complicated scrub typhus patients (n = 181), multivariate analysis showed that only APACHE II score was an independent risk factor for mortality (95% confidence interval, 1.11 to 1.56; P < 0.001). Our data suggest that outcomes of azithromycin therapy are comparable to those of doxycycline therapy in patients with complicated scrub typhus. PMID:24366734
Seroepidemiology of rickettsial infections in Northeast India.
Khan, Siraj Ahmed; Bora, Trishna; Chattopadhyay, Suchismita; Jiang, Ju; Richards, Allen L; Dutta, Prafulla
2016-08-01
Resurgence of scrub typhus was reported in Northeast India in 2010 after a gap of 67 years since World War II. However, the presence of other rickettsial infections remained unknown from this region. A seroepidemiological investigation was undertaken in the scrub typhus affected areas from 2013-2015 in Assam, Arunachal Pradesh and Nagaland to assess the exposure to other rickettsial diseases besides scrub typhus. Samples were collected from people residing in scrub typhus reporting areas. Serology was performed by an indirect ELISA for the three rickettsial agents' viz., scrub typhus group orientiae (STGO), spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR). A sample with total net absorbance ≥1.000 was considered as positive. An entomological survey was also carried out in the affected areas. Overall, 1265 human blood samples were collected, of which 30.8% (n=390), 13.8% (175) and 4.2% (53) had antibodies against STGO, SFGR and TGR respectively. Presence of antibodies against more than one of the rickettsial groups was also detected. Among the arthropods collected, chiggers of Leptotrombidium deleinse, fleas belonging to Ctenocephalides felis and Pulex irritans, ticks belonging to Rhipicephalus microplus, Haemaphysalis spp. were predominant. Candidatus Rickettsia senegalensis was detected in C. felis. Our findings confirm wide circulation of rickettsial infections and their probable vectors in the northeast region of India.Accession numbers: KU163367, KU163368, KU499847, KU499848. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
USDA-ARS?s Scientific Manuscript database
Leptotrombidium chiangraiensis Tanskul and Linthicum and Leptotrombidium imphalum Vercammen-Grandjean are important vectors of scrub typhus in ricefield habitats in northern Thailand. The developmental biology of all stages of the life cycle of two generations of mites infected with Orientia tsutsug...
Scrub Typhus Leading to Acute Encephalitis Syndrome, Assam, India.
Khan, Siraj A; Bora, Trishna; Laskar, Basanta; Khan, Abdul M; Dutta, Prafulla
2017-01-01
To determine the contribution of Orientia tsutsugamushi, the agent of scrub typhus, as a cause of acute encephalitis syndrome (AES) in Assam, India, we conducted a retrospective study of hospital patients with symptoms of AES during 2013-2015. Our findings suggest that O. tsutsugamushi infection leads to AES and the resulting illness and death.
A case series of possibly recrudescent Orientia tsutsugamushi infection presenting as pneumonia.
Im, Jae-Hyoung; Baek, Ji Hyeon; Lee, Jin-Soo; Chung, Moon-Hyun; Lee, Sun Myoung; Kang, Jae-Seung
2014-01-01
Orientia tsutsugamushi remains latent in humans after scrub typhus. Pneumonia occurs as a complication of scrub typhus in the late-phase disease. However, pneumonia may also occur as a presenting manifestation of O. tsutsugamushi infection. We reviewed the cases of 3 patients with atypical pneumonia who presented at our hospital and were later confirmed to have O. tsutsugamushi infection by serology, nested polymerase chain reaction (PCR), and cell culture. All patients were young adults with no history of scrub typhus, and none claimed to have recently been exposed to areas where scrub typhus is endemic. Two cases occurred in non-outbreak seasons. Furthermore, eschar was not observed. Pneumonia was documented within 4 days after fever onset. The immunoglobulin (Ig) G antibody titers against O. tsutsugamushi were higher than the IgM titers, although the serologic test results were less helpful in the diagnosis. Nested PCR and cell culture of blood specimens confirmed the diagnosis of O. tsutsugamushi infection. These findings suggest that pneumonia can occur as a result of recrudescence of latent O. tsutsugamushi infection.
Persistence of Orientia tsutsugamushi in humans.
Chung, Moon-Hyun; Lee, Jin-Soo; Baek, Ji-hyeon; Kim, Mijeong; Kang, Jae-Seung
2012-03-01
We investigated the persistence of viable Orientia tsutsugamushi in patients who had recovered from scrub typhus. Blood specimens were available from six patients with scrub typhus who were at 1 to 18 months after the onset of the illness. The EDTA-treated blood specimens were inoculated into ECV304 cells, and cultures were maintained for 7 months. Sequencing of the 56-kDa type-specific antigen gene of O. tsutsugamushi was performed to ascertain the homology of isolates. O. tsutsugamushi was isolated from all six patients, and nucleotide sequences of isolates serially collected from each patient were identical in all five patients in whom nucleotide sequences were compared. One patient relapsed 2 days after completion of antibiotic therapy; two patients complained of weakness for 1 to 2.5 months after the illness; one patient underwent coronary angioplasty 6 months later; and one patient suffered from a transient ischemic attack 8 months later. This finding suggests that O. tsutsugamushi causes chronic latent infection, which may be associated with certain clinical illnesses, preceded by scrub typhus. Antibiotic therapy abates the symptoms of scrub typhus, but does not eradicate O. tsutsugamushi from the human body.
Scrub typhus masquerading as HELLP syndrome and puerperal sepsis in an asymptomatic malaria patient.
Karim, Habib Md Reazaul; Bhattacharyya, Prithwis; Kakati, Sonai Datta; Borah, Tridip Jyoti; Yunus, Md
2016-01-01
Scrub typhus and malaria can involve multiple organ systems and are notoriously known for varied presentations. However, clinical malaria or scrub typhus is unusual without fever. On the other hand, altered sensorium with or without fever, dehydration, hemorrhage and hemolysis may lead to low blood pressure. Presence of toxic granules and elevated band forms in such patients can even mimic sepsis. When such a patient is in the peripartum period, it creates a strong clinical dilemma for the physician especially in unbooked obstetric cases. We present such a case where a 26-year-old unbooked female presented on second postpartum day with severe anemia, altered sensorium, difficulty in breathing along with jaundice and gum bleeding without history of fever. Rapid diagnostic test for malaria was negative and no eschar was seen. These parameters suggested a diagnosis of HELLP (Hemolysis, Elevated Liver enzymes, Low Platelet) syndrome with or without puerperal sepsis. Subsequently she was diagnosed as having asymptomatic malaria and scrub typhus and responded to the treatment of it. The biochemical changes suggestive of HELLP syndrome also subsided. We present this case to emphasize the fact that mere absence of fever and eschar does not rule out scrub typhus. It should also be considered as a differential diagnosis in patients with symptoms and signs suggesting HELLP syndrome. Asymptomatic malaria can complicate case scenario towards puerperal sepsis by giving false toxic granules and band form in such situations.
Clinical profile and outcome of children with scrub typhus from Chennai, South India.
Ganesh, Ramaswamy; Suresh, Natarajan; Pratyusha, L L; Janakiraman, Lalitha; Manickam, Mani; Andal, A
2018-06-01
Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi. We prospectively studied the clinico-laboratory profile and outcome of 358 children aged 1 day to 18 years diagnosed with scrub typhus from Chennai, South India. All children (100%) had fever. Eschar was seen in 67%. All children were treated with oral doxycycline and those with complications were treated with intravenous chloramphenicol/azithromycin. Rapid defervescence (within 48 h) after initiation of doxycline was seen in 306 (85%) and 52 (14.5%) developed complications. Multivariate logistic regression analysis revealed that children who had an elevated aspartate amino transferase (> 120 IU/L) and the presence of thrombocytopenia (platelet count less than 1 lac cells/mm 3 ) at admission had high risk of developing complications. The overall mortality rate in this series was 0.8%. Our 4-year study highlights the clinico-laboratory profile of Scrub typhus in children from Chennai, South India. Early recognition and prompt treatment reduces the complication and mortality. What is Known: • Scrub typhus is endemic to tsutsugamushi triangle, a geographical triangle extending from northern Japan in the east to Pakistan and Afghanistan in the west and northern Australia in the south. • There is paucity of data regarding its clinico-laboratory profile in neonates as well as its predictors of outcome. What is New: • Children who had an elevated AST and the presence of thrombocytopenia at admission had high risk of developing complications.
Pote, Kiran; Narang, Rahul; Deshmukh, Pradeep
2018-01-01
Differentiating scrub typhus from other acute febrile illness is difficult due to non specificity of clinical symptoms and relative absence of eschar in Indian population. The diagnosis thus relies mainly on laboratory tests. Antibody based serological tests are mainstay of scrub typhus diagnosis. Here, we evaluated the diagnostic performance of IgM ELISA, IgM IFA and ICT to detect antibodies against O. tsutsugamushi in acute serum of febrile patients. The serum samples from 600 randomly selected patients suffering from acute undifferentiated fever were tested by all the three tests mentioned above. We used latent class analysis to generate unbiased results as all the tests for scrub typhus diagnosis are imperfect and none of them can be considered as reference standard. We found that IgM ELISA with cutoff titer 0.5 OD has high diagnostic accuracy (sensitivity 99.9% and specificity 99.15) than IgM IFA (sensitivity 96.8% and specificity 99.7%) for scrub typhus diagnosis. ICT used in our study had very high specificity 100% but low sensitivity (38%) which would limit its use for acute serum samples. ICT being a screening or point of care test, has to be more sensitive while some compromise with specificity is affordable. Hence, optimal cutoff for ICT should be evaluated under different settings. IgM ELISA being simple and affordable could be an alternative diagnostic test to IgM IFA which is subjective and costly.
Roh, Jong Yul; Song, Bong Gu; Park, Won Il; Shin, Eun Hee; Park, Chan; Park, Mi-Yeoun; Chang, Kyu Sik; Lee, Wook Gyo; Lee, Hee Il; Shin, E-Hyun
2014-01-01
To clarify the geographical distribution of scrub typhus vectors in Korea, a survey of larval trombiculid mites was conducted from 2005 to 2007 by collecting wild small mammals twice a year (spring and autumn) at 24 sites nationwide. A total of 67,325 mites representing 4 genera and 14 species were collected from 783 trapped rodents, corresponding to a chigger index (number of chigger mites per rodent) of 86.0. The predominant mite species were Leptotrombidium pallidum (52.6%), Leptotrombiduim scutellare (27.1%), Leptotrombidium palpale (8.2%), Leptotrombidium orientale (5.6%), and Neotrombicula tamiyai (1.7%). However, the proportions of L. scutellare in southern areas, including endemic provinces such as Jeollabuk-Do (34.3%), Jeollanam-Do (49.0%), and Gyeongsangnam-Do (88%), were relatively higher than in central Korean regions where L. pallidum was predominant. In autumn, the ratio of L. scutellare increased to 42% while the ratio of L. pallidum decreased. The geographical distribution map of the L. scutellare chigger index was identical to the incidence pattern of scrub typhus, whereas those of overall mites and L. pallidum showed no relationship with case incidence patterns. Distribution mapping analysis shows an identical geographical distribution of L. scutellare and epidemic incidence of scrub typhus in South Korea. L. pallidum could be another vector at all other parts of the Korean peninsula, including the eastern and northern regions that have a low level of scrub typhus incidence.
Paris, Daniel H; Blacksell, Stuart D; Nawtaisong, Pruksa; Jenjaroen, Kemajittra; Teeraratkul, Achara; Chierakul, Wirongrong; Wuthiekanun, Vanaporn; Kantipong, Pacharee; Day, Nicholas P J
2011-09-01
There is an urgent need to develop rapid and accurate point-of-care (POC) technologies for acute scrub typhus diagnosis in low-resource, primary health care settings to guide clinical therapy. In this study we present the clinical evaluation of loop-mediated isothermal PCR assay (LAMP) in the context of a prospective fever study, including 161 patients from scrub typhus-endemic Chiang Rai, northern Thailand. A robust reference comparator set comprising following 'scrub typhus infection criteria' (STIC) was used: a) positive cell culture isolate and/or b) an admission IgM titer ≥1∶12,800 using the 'gold standard' indirect immunofluorescence assay (IFA) and/or c) a 4-fold rising IFA IgM titer and/or d) a positive result in at least two out of three PCR assays. Compared to the STIC criteria, all PCR assays (including LAMP) demonstrated high specificity ranging from 96-99%, with sensitivities varying from 40% to 56%, similar to the antibody based rapid test, which had a sensitivity of 47% and a specificity of 95%. The diagnostic accuracy of the LAMP assay was similar to realtime and nested conventional PCR assays, but superior to the antibody-based rapid test in the early disease course. The combination of DNA- and antibody-based detection methods increased sensitivity with minimal reduction of specificity, and expanded the timeframe of adequate diagnostic coverage throughout the acute phase of scrub typhus.
Chest radiographic manifestations of scrub typhus.
Abhilash, Kpp; Mannam, P R; Rajendran, K; John, R A; Ramasami, P
2016-01-01
Respiratory system involvement in scrub typhus is seen in 20-72% of patients. In endemic areas, good understanding and familiarity with the various radiologic findings of scrub typhus are essential in identifying pulmonary complications. Patients admitted to a tertiary care center with scrub typhus between October 2012 and September 2013 and had a chest X ray done were included in the analysis. Details and radiographic findings were noted and factors associated with abnormal X-rays were analyzed. The study cohort contained 398 patients. Common presenting complaints included fever (100%), generalized myalgia (83%), headache (65%), dyspnea (54%), cough (24.3%), and altered sensorium (14%). Almost half of the patients (49.4%) had normal chest radiographs. Common radiological pulmonary abnormalities included pleural effusion (14.6%), acute respiratory distress syndrome (14%), airspace opacity (10.5%), reticulonodular opacities (10.3%), peribronchial thickening (5.8%), and pulmonary edema (2%). Cardiomegaly was noted in 3.5% of patients. Breathlessness, presence of an eschar, platelet counts of <20,000 cells/cumm, and total serum bilirubin >2 mg/dL had the highest odds of having an abnormal chest radiograph. Patients with an abnormal chest X-ray had a higher requirement of noninvasive ventilation (odds ratio [OR]: 13.98; 95% confidence interval CI: 5.89-33.16), invasive ventilation (OR: 18.07; 95% CI: 6.42-50.88), inotropes (OR: 8.76; 95% CI: 4.35-17.62), higher involvement of other organ systems, longer duration of hospital stay (3.18 ± 3 vs. 7.27 ± 5.58 days; P< 0.001), and higher mortality (OR: 4.63; 95% CI: 1.54-13.85). Almost half of the patients with scrub typhus have abnormal chest radiographs. Chest radiography should be included as part of basic evaluation at presentation in patients with scrub typhus, especially in those with breathlessness, eschar, jaundice, and severe thrombocytopenia.
Renal Manifestation in Scrub Typhus during a Major Outbreak in Central Nepal.
Sedhain, A; Bhattarai, G R
2017-01-01
Renal involvement and acute kidney injury (AKI) are common clinical manifestations seen in scrub typhus, a vector-borne tropical disease. There are no data on renal manifestation in scrub typhus in Nepal. We conducted a prospective study to analyze the incidence, urinary abnormalities, course, severity, outcome, and the predictors of AKI in patients with scrub typhus during a major outbreak in Central Nepal. Total 1398 patients admitted with acute febrile illness were subjected for Scrub Typhus Detect™ Immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) test, of which 502 (35.90%) patients tested positive and were included in the study. Mean age of the patients was 30.37 ± 18.81 years (range, 1-79 years) with 26.29% in the pediatric age group. Female-to-male ratio was 1.26:1. Mean duration of fever was 6.8 ± 3.1 days. Mean IgM ELISA value for scrub typhus was 2.17 ± 1.70 without difference in AKI and non-AKI groups (2.17 ± 1.76 vs. 2.16 ± 1.62; P = 0.94). Urinary abnormalities were seen in 42.3% of patients. Mean serum creatinine was 1.37 ± 0.69 mg/dl with significant difference in two groups (1.85 ± 0.87 vs. 1.03 ± 0.17; P = 0.003). AKI was seen in 35.8% of patients with majority having Stage 1 AKI (68.3%) followed by Stage 2 (34.1%) and Stage 3 (1.2%). Hemodialysis was required for 3.94% of patients. In 54% of patients, AKI occurred in fifth and sixth day of fever. ICU admission was required for 18.73% of patients and 8.57% required ventilator support. Mortality rate was 1.79%, which was higher among patients with AKI (2.96% vs. 1.0%; P = 0.106). Multivariate analysis revealed that the presence of pneumonia, shock, and acute respiratory distress syndrome predicted the development of AKI.
Candasamy, Sadanandane; Ayyanar, Elango; Paily, Kummankottil; Karthikeyan, Patricia Anitha; Sundararajan, Agatheswaran; Purushothaman, Jambulingam
2016-12-01
Human cases of scrub typhus are reported every year from Puducherry and adjoining areas in southern India. However, information on the presence of causative agent, Orientia tsutsugamushi, and its vectors is lacking. Hence, the objective of the study was to find out the vector as well as pathogen distribution in rodents and shrews present in the scrub typhus-reported areas in southern India. Trombiculid mites were collected by combing rats and shrews collected using Sherman traps and identified to species level following standard taxonomical keys. The serum samples of the animals were used for Weil-Felix test and the clots containing blood cells were used for DNA extraction and polymerase chain reaction (PCR). A total of 181 animals comprising four rodent species and one shrew species were collected from 12 villages. High proportion of chiggers was collected from the shrew, Suncus murinus (79.1%) and Rattus rattus (47.6%). A total of 10,491 trombiculid mites belonging to nine species were collected. Leptotrombidium deliense, the known vector of scrub typhus pathogen, was the predominant species (71.0%) and the chigger (L. deliense) index was 41.1 per animal. Of the 50 animals screened for the pathogen, 28 showed agglutination against OX-K in Weil-Felix test indicating the presence of antibodies against O. tsutsugamushi, the causative agent of scrub typhus. PCR carried out with the DNA extracted from blood samples of two of the animals were positive for GroEl gene of O. tsutsugamushi. L. deliense index was well above the critical limit of chigger load, indicating that all the villages were receptive for high risk of transmission of scrub typhus to human. Pathogen positivity was higher among animals collected from villages recorded for higher chigger indices due to active transmission between the chigger mites and reservoir host animals. The results are suggestive of routine vector/pathogen surveillance at hot spots to initiate timely preventive measures.
Blacksell, Stuart D; Paris, Daniel H; Chierakul, Wirongrong; Wuthiekanun, Vanaporn; Teeratakul, Achara; Kantipong, Pacharee; Day, Nicholas P J
2012-03-01
Samples from 160 prospectively recruited febrile patients with typhus-like illness in an area of Thailand (Chiang Rai, northern Thailand) where scrub typhus is endemic were used to evaluate the diagnostic capabilities of four rapid immunochromatographic tests (ICTs) for the detection of Orientia tsutsugamushi IgM and total antibodies during acute scrub typhus infection. Of the 160 cases, 54 (34%) had been confirmed to have scrub typhus using the reference scrub typhus infection criteria (STIC), i.e., positive cell culture isolation, an admission IgM antibody titer of ≥1:12,800, a 4-fold rising IgM antibody titer, and/or positivity for ≥2 out of 3 PCR gene targets). The ICTs gave the following sensitivities and specificities: the Panbio IgM ICT, 46% (95% confidence interval [CI], 33 to 60) and 95% (95% CI, 89 to 98), respectively; the Standard Diagnostics IgM ICT, 68% (95% CI, 60 to 75) and 73% (95% CI, 68 to 78), respectively; the AccessBio IgM ICT, 56% (95% CI, 48 to 63) and 90% (95% CI, 87 to 94), respectively; and the AccessBio total antibody ABt ICT, 61% (95% CI, 53 to 68) and 68% (95% CI, 63 to 73), respectively. An isothermal loop amplification (LAMP) PCR assay for scrub typhus demonstrated a sensitivity of 52% (95% CI, 38 to 66) and a specificity of 94% (95% CI, 88 to 98). This study has revealed the diagnostic limitations of antibody-based assays in an acute care setting. However, the combination of ICTs with LAMP usually increased sensitivity with a minimal reduction in specificity. The best combination, the Panbio IgM ICT and LAMP, resulted in a sensitivity of 67% (95% CI, 53 to 79) and a specificity of 91% (95% CI, 83 to 95). The combination of antibody-based assays with DNA- or antigen-based tests shows promise for improved diagnostic sensitivity.
Differences in agricultural activities related to incidence of scrub typhus between Korea and Japan.
Ma, Chang-Jin; Oh, Gyung-Jae; Kang, Gong-Unn; Lee, Jeong Mi; Lee, Da-Un; Nam, Hae-Sung; Ryu, So Yeon; Lee, Young-Hoon
2017-01-01
The purpose of this study was to establish a basis for improving or strengthening the preventive strategy against scrub typhus in Korea by comparing and analyzing the difference of prevention behaviors contributing to the occurrence of scrub typhus in Japan and Korea. The survey was carried out in Jeollabuk-do, which is a high risk and high incidence area, and Fukuoka Prefecture, which is a high risk and low incidence area. The study included 406 Korean farmers and 216 Japanese farmers. Data were collected through face-to-face surveys by interviewers who had completed standardized education. Korean farmers have a higher percentage of agricultural working posture that involved contact with weeds than Japanese farmers (p<0.05). The frequency and proportion of weeding were lower in Korean farmers than in Japanese farmers (p<0.05). The level of knowledge about scrub typhus was significantly higher among Korean farmers than among Japanese farmers (p<0.05). Mostly, the behavior of agriculture work was more appropriate for Japanese farmers than for Korean farmers (p<0.05). The total average level of agricultural work was lower in Korea than in Japan, lower in men than women, and lower in part-time farmers than full-time farmers (p<0.05). This study suggests that it is reasonable to develop and provide a program that can improve the level of preventive behavior taking into consideration the characteristics of the subject in order to reduce the incidence of diseases in high-risk areas for scrub typhus.
Severe scrub typhus infection: Clinical features, diagnostic challenges and management
Peter, John Victor; Sudarsan, Thomas I; Prakash, John Anthony J; Varghese, George M
2015-01-01
Scrub typhus infection is an important cause of acute undifferentiated fever in South East Asia. The clinical picture is characterized by sudden onset fever with chills and non-specific symptoms that include headache, myalgia, sweating and vomiting. The presence of an eschar, in about half the patients with proven scrub typhus infection and usually seen in the axilla, groin or inguinal region, is characteristic of scrub typhus. Common laboratory findings are elevated liver transaminases, thrombocytopenia and leukocytosis. About a third of patients admitted to hospital with scrub typhus infection have evidence of organ dysfunction that may include respiratory failure, circulatory shock, mild renal or hepatic dysfunction, central nervous system involvement or hematological abnormalities. Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis. Serological assays are the mainstay of diagnosis as they are easy to perform; the reference test is the indirect immunofluorescence assay (IFA) for the detection of IgM antibodies. However in clinical practice, the enzyme-linked immuno-sorbent assay is done due to the ease of performing this test and a good sensitivity and sensitivity when compared with the IFA. Paired samples, obtained at least two weeks apart, demonstrating a ≥ 4 fold rise in titre, is necessary for confirmation of serologic diagnosis. The mainstay of treatment is the tetracycline group of antibiotics or chloramphenicol although macrolides are used alternatively. In mild cases, recovery is complete. In severe cases with multi-organ failure, mortality may be as high as 24%. PMID:26261776
A study of muscle involvement in scrub typhus.
Kalita, Jayantee; Misra, Usha K; Mani, Vinita E; Mahadevan, Anita; Shankar, Susrala K
2015-01-15
Patients with scrub typhus often complain of myalgia, but a comprehensive study on muscle dysfunction is lacking. We therefore report the clinical, electromyographic and muscle biopsy findings in patients with scrub typhus. Consecutive patients with scrub typhus were included, and their clinical and laboratory findings were noted. The patients with myalgia or weakness and elevated serum creatine kinase (CK) were considered to have muscle involvement. Electromyography (EMG) and muscle biopsy were done in some patients. Patients were treated with doxycycline 200mg daily for 7 days, and their clinical and biochemical outcome on discharge and one month were evaluated. 13 out of 33 (39.4%) patients had muscle involvement and their CK levels ranged between 287 and 3166 (859 ± 829) U/L. EMG revealed short duration polyphasic potentials, and muscle histopathology revealed evidence of vasculitis. There were significant correlations between severity of weakness and CK levels (r = -0.6; p < 0.001), platelet counts (r = 0.4; p = 0.04), duration of illness (r = -0.4; p = 0.01) and disability on discharge (r = -0.4; p = 0.04). Patients with muscle involvement had more severe illness evidenced by a lower Glasgow Coma Scale score (p < 0.001), thrombocytopenia (p = 0.05) and greater disability on discharge (p = 0.007), when compared to those without muscle involvement. All the patients had complete recovery following doxycycline therapy, and CK levels also normalized. Muscle dysfunction was present in 39% patients with scrub typhus. Although muscle histopathology showed evidence of vasculitis, patients responded to doxycycline. Copyright © 2014 Elsevier B.V. All rights reserved.
Differences in agricultural activities related to incidence of scrub typhus between Korea and Japan
2017-01-01
OBJECTIVES The purpose of this study was to establish a basis for improving or strengthening the preventive strategy against scrub typhus in Korea by comparing and analyzing the difference of prevention behaviors contributing to the occurrence of scrub typhus in Japan and Korea. METHODS The survey was carried out in Jeollabuk-do, which is a high risk and high incidence area, and Fukuoka Prefecture, which is a high risk and low incidence area. The study included 406 Korean farmers and 216 Japanese farmers. Data were collected through face-to-face surveys by interviewers who had completed standardized education. RESULTS Korean farmers have a higher percentage of agricultural working posture that involved contact with weeds than Japanese farmers (p<0.05). The frequency and proportion of weeding were lower in Korean farmers than in Japanese farmers (p<0.05). The level of knowledge about scrub typhus was significantly higher among Korean farmers than among Japanese farmers (p<0.05). Mostly, the behavior of agriculture work was more appropriate for Japanese farmers than for Korean farmers (p<0.05). The total average level of agricultural work was lower in Korea than in Japan, lower in men than women, and lower in part-time farmers than full-time farmers (p<0.05). CONCLUSIONS This study suggests that it is reasonable to develop and provide a program that can improve the level of preventive behavior taking into consideration the characteristics of the subject in order to reduce the incidence of diseases in high-risk areas for scrub typhus. PMID:29121711
2009-01-01
leptospirosis in South Vietnam. A study in 150 patients. Annals of Internal Medicine. 1973 Aug;79(2):167-73. 3. Berman SJ, Kundin WD. Scrub typhus in South...Berman SJ. Scrub typhus . In: Hoeprich PD, Jordan MC, Ronald AR, eds. Infectious Diseases 5th ed. Philadelphia: JB Lippincott, 1994. Chapter 113
Sivarajan, Sunuraj; Shivalli, Siddharudha; Bhuyan, Debomallya; Mawlong, Michael; Barman, Rittwick
2016-10-05
India is an integral component of "tsutsugamushi triangle" which depicts a part of the globe endemic to scrub typhus. Owing to frequent outbreaks witnessed in different parts of the country in the recent past, scrub typhus is described as a re-emerging infectious disease in India. The present study aimed to study the clinical and paraclinical profile, complications and predictors of outcome among 90 cases of scrub typhus diagnosed in a hospital of north-eastern India from Sept 2011 to Aug 2012. A longitudinal study was conducted in a hospital of Meghalaya, India between Sept 2011 and Aug 2012. Diagnosis of scrub typhus was arrived by SD BIOLINE tsutsugamushi (solid phase immunochromatographic assay) rapid diagnostic test for antibodies (IgM, IgG or IgA). Descriptive analyses of age, gender, geographic area, symptoms and signs, treatment, laboratory findings, complications, and outcome were conducted. Relative risk (RR) with 95 % confidence interval (CI) was computed for Multiple Organ Dysfunction Syndrome (MODS) and mortality. Binary logistic regression was applied to the significant correlates (P < 0.05) on univariate analysis to identify the predictors of MODS and mortality in scrub typhus. As many as 662 clinically suspected scrub typhus patients were tested and 90 (13.6 %) were diagnosed to have scrub typhus. Out of 90 patients, 52.2 % (n = 47) were males and their mean (SD) age was 36.29 (13.38) years. Fever of <7 days (n = 75, 83.3 %), myalgia (n = 56, 62.2 %), pain abdomen (n = 24, 26.7 %), headache (n = 24, 26.7 %), nausea/vomiting (n = 21, 23.3 %), dry cough (n = 21, 23.3 %), hepatomegaly (n = 24, 26.7 %), splenomegaly (n = 22, 24.4 %), and lymphadenopathy (n = 20, 22.2 %) were the predominant clinical features. Eschar was seen in 10 patients (11.1 %). One third (n = 30) of the patients developed at least one systemic complication. Acute hepatitis (n = 15, 16.7 %), pneumonitis (n = 14, 15.6 %), and acute kidney injury (n = 11, 12.2 %) were the common complications. MODS was seen in 14.4 % (n = 13) and 38.5 % (n = 5) of the patients with MODS died. Overall, case fatality rate was 5.15 % (n = 5). On univariate analysis, platelets <100 000/mm 3 , serum creatinine >1.5 mg/dl, and transaminase (AST, ALT or both) >500 U/L were associated with MODS (P < 0.001) and mortality (P < 0.05). In addition, serum bilirubin >3 mg/dl was also associated with MODS (P < 0.001). On applying binary logistic regression, serum creatinine >1.5 mg/dl was a predictor of MODS (OR: 76.1, 95 % CI: 4.9-1175.6) and mortality (OR: 18.03, 95 % CI: 1.38-235.1). In this study setting, approximately one-seventh (13.6 %) of the acute undifferentiated febrile illness were due to scrub typhus. Systemic complications were common (33.3 %). Serum creatinine >1.5 mg/dl was a predictor of MODS and mortality.
Hwang, Kyungo; Jang, Ha Nee; Lee, Tae Won; Cho, Hyun Seop; Bae, Eunjin; Chang, Se-Ho; Park, Dong Jun
2017-03-15
Renal involvement in scrub typhus ranges from simple urinary abnormalities to acute kidney injury (AKI) leading to death. This study evaluated the incidence, predictors and prognosis of AKI associated with scrub typhus according to the RIFLE (risk, injury, failure, loss, end-stage kidney disease) criteria. We retrospectively evaluated the medical records of patients diagnosed with scrub typhus from January 2001 to November 2013 in Gyeongsang National University Hospital. During the study period, 510 patients were diagnosed with scrub typhus and the incidence of AKI was 35.9%. There were 132 (25.9%) patients at risk, 37 (7.3%) with injury and 14 (2.7%) with failure. In comparison with the non-AKI group, the AKI group was older (73.9 vs 63.4 years, p<0.001) and had more comorbidities such as hypertension, diabetes mellitus and chronic kidney disease (CKD). AKI frequently occurs in hypertensive patients taking angiotensin receptor blockers or ACE inhibitors (p=0.002), and in patients with diabetes with higher glycated haemoglobin levels (p=0.033). Haematuria and proteinuria were more frequent in the AKI group. There was no relationship between the severity of proteinuria and occurrence of AKI. Intensive care unit admission and death were more frequent in the AKI group. The renal function of most patients with AKI recovered without sequelae, except for 1 patient who had underlying CKD. Multivariate analysis showed that age, presence of CKD, serum albumin level and time to hospital presentation after symptom onset were independent predictors of AKI in patients with scrub typhus. Our current results suggest that the presence of underlying CKD, older age, lower serum albumin level and time to hospital presentation after symptom onset were important risk factors to determine occurrence of AKI. Whether earlier diagnosis and treatment in patients with the above risk factors reduce the incidence and severity of AKI deserves to be investigated. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
[Spatial analysis of autumn-winter type scrub typhus in Shandong province, 2006-2014].
Yang, H; Bi, Z W; Kou, Z Q; Zheng, L; Zhao, Z T
2016-05-01
To discuss the spatial-temporal distribution and epidemic trends of autumn-winter type scrub typhus in Shandong province, and provide scientific evidence for further study for the prevention and control of the disease. The scrub typhus surveillance data during 2006-2014 were collected from Shandong Disease Reporting Information System. The data was analyzed by using software ArcGIS 9.3(ESRI Inc., Redlands, CA, USA), GeoDa 0.9.5-i and SatScan 9.1.1. The Moran' s I, log-likelihood ratio(LLR), relative risk(RR)were calculated and the incidence choropleth maps, local indicators of spatial autocorrelation cluster maps and space scaning cluster maps were drawn. A total of 4 453 scrub typhus cases were reported during 2006-2014, and the annual incidence increased with year. Among the 17 prefectures(municipality)in Shandong, 13 were affected by scrub typhus. The global Moran's I index was 0.501 5(P<0.01). The differences in local Moran' s I index among 16 prefectures were significant(P<0.01). The " high-high" clustering areas were mainly Wulian county, Lanshan district and Juxian county of Rizhao, Xintai county of Tai' an, Gangcheng and Laicheng districts of Laiwu, Yiyuan county of Zibo and Mengyin county of Linyi. Spatial scan analysis showed that an eastward moving trend of high-risk clusters and two new high-risk clusters were found in Zaozhuang in 2014. The centers of the most likely clusters were in the south central mountainous areas during 2006-2010 and in 2012, eastern hilly areas in 2011, 2013 and 2014, and the size of the clusters expanded in 2008, 2011, 2013 and 2014. One spatial-temporal cluster was detected from October 1, 2014 to November 30, 2014, the center of the cluster was in Rizhao and the radius was 222.34 kilometers. A positive spatial correlation and spatial agglomerations were found in the distribution of autumn-winter type scrub typhus in Shandong. Since 2006, the epidemic area of the disease has expanded and the number of high-risk areas has increased. Moreover, the eastward moving and periodically expanding trends of high-risk clusters were detected.
Jang, Mi-Ok; Kim, Ji Eun; Kim, Uh Jin; Ahn, Joon Hwan; Kang, Seung-Ji; Jang, Hee-Chang; Jung, Sook-In; Park, Kyung-Hwa
2014-01-01
Age can affect the clinical features and severity of infectious disorders, such as scrub typhus. We performed this study to examine differences between elderly and non-elderly scrub typhus patients, and to identify risk factors predictive of disease outcomes. This retrospective study included patients admitted to a tertiary hospital with scrub typhus between 2001 and 2011. A total of 615 patients were enrolled in this study, 328 of which were >65 years of age. Of the elderly patients, 46.0% (151/328) experienced at least one complication compared to only 23.0% (66/287) in younger patients. A linear trend was observed between age and complication rates (p=0.002). The most common complication in elderly patients was acute kidney injury (75, 22.9%). Treatment failure was reported in 10 elderly patients (3.0%) compared to one non-elderly patient (0.3%). Mental confusion and dyspnea of clinical manifestations at admission were common in elderly patients. Frequency of fever, rash, and eschar were similar in both groups. The following four factors were significantly associated with severe scrub typhus in elderly patients: (1) white blood cell (WBC) counts>10,000/mm(3) (OR=2.569, CI=1.298-5.086), (2) MDRD GFR<60mL/min (OR=3.525, CI=1.864-6.667), (3) albumin≤3.0g/dL (OR=4.976, CI=2.664-9.294), and (4) acute physiology and chronic health evaluation II (APACHE II) score>10 points (OR=3.304, CI=1.793-60.87). Complications and mortality were more common in elderly patients, often associated with delays in diagnosis and treatment. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Rickettsia Felis in Xenopsylla Cheopis, Java, Indonesia
2006-08-01
Sardjono TW, Yanuwiadi B, Hernowati TE, et al. Seroepidemiological evidence for murine and scrub typhus in Malang, Indonesia. Am J Trop Med Hyg. 1997;57...and Allen L. Richards* Rickettsia typhi and R. felis, etiologic agents of murine typhus and fleaborne spotted fever, respectively, were detected in...Indonesia and nat- urally occurring R. felis in Oriental rat fleas. Murine typhus (endemic typhus , fleaborne typhus ),caused by Rickettsia typhi, is
Janardhanan, Jeshina; Trowbridge, Paul; Varghese, George M
2014-12-01
Scrub typhus is an acute febrile illness that, if untreated, can result in considerable morbidity and mortality. One of the primary reasons for delays in the treatment of this potentially fatal infection is the difficulty in diagnosing the condition. Diagnosis is often complicated because of the combination of non-specific symptoms that overlap with other infections commonly found in endemic areas and the poor available diagnostics. In the majority of the endemic settings, diagnosis still relies on the Weil-Felix test, which is neither sensitive nor specific. Other methods of testing have become available, but at this time, these remain insufficient to provide the rapid point-of-care diagnostics that would be necessary to significantly change the management of this infection by providers in endemic areas. This article reviews the currently available diagnostic tools for scrub typhus and their utility in the clinical setting.
Risk of Relapse Associated with Doxycycline Therapy for Scrub Typhus
1981-01-01
143150-9 202 Rickettsiae ard Rickettsial Diseases I. INTRODUCTION Chloramphenicol (Chloromycetin) or oxytetracycline (Terra- mycin) are the drugs...doses of oxytetracycline in a double blind, randomized trial conducted in a population of scrub typhus patients who were exposed in the Pescadores... oxytetracycline , 500 mg every 6 hrs for 7 days (OXY, 23 patients). Drug and placebo were manufactured in such a way and administered every 6 hrs for 7
Clinical Predictors of Multiple Organ Dysfunction Syndromes in Pediatric patients with Scrub Typhus.
Zhao, Dongying; Zhang, Yongjun; Yin, Zhaoqing; Zhao, Jing; Yang, Defeng; Zhou, Qun
2017-06-01
Scrub typhus can produce multiple organ dysfunction syndrome (MODS). Early recognition of the patients at risk of MODS would be helpful in providing timely management and reducing the mortality. In all, 449 children with scrub typhus were enrolled at three hospitals in Yunnan, China from January 2010 to January 2015. The patients' clinical status of organ system dysfunction was evaluated on the day of discharge from hospital by using standard criteria. The patients were classified into MODS present (64 cases, 14.3%) or MODS absent (385 cases, 85.7%). Multivariate logistic regression analyses revealed that the prognostic factors for MODS included skin rash (odds ratio, OR = 3.3, p = 0.037), time interval form treatment to defervescence (OR = 1.2, p = 0.035), hemoglobin (OR = 0.54, p = 0.041), platelet counts (OR = 0.06, p < 0.001), aspartate-aminotransferase (OR = 4.7, p = 0.011) and total bilirubin (OR = 2.3, p = 0.013). By describing risk factors resulting in MODS in pediatric scrub typhus, our study provides clinicians with important information to improve the clinical monitoring and prognostication of MODS. © The Author [2016]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Scrub Typhus: A Clinico-Laboratory Differentiation of Children with and without Meningitis.
Bhat, Nowneet Kumar; Pandita, Neerul; Saini, Manju; Dhar, Minakshi; Ahmed, Sohaib; Shirazi, Nadia; Wasim, Sanober; Shirke, Rupali; Chandar, Vipan
2016-06-01
Neurological involvement in the form of meningitis or meningoencephalitis, although well documented in scrub typhus, has not been extensively studied in the pediatric population. We report the clinical and laboratory profile of 96 children with scrub typhus and compared those with and without meningitis. Twenty seven (28%) children had clinical and laboratory evidence of meningitis. The most frequent presenting features were fever (100%), meningeal signs (66.6%), nausea and vomiting (56.3%), seizures (55.5%) and altered sensorium (51.8%). The children with meningitis presented early and had significantly lower respiratory and renal impairments when compared with the non-meningitis group. Cerebrospinal fluid (CSF) analysis revealed elevated total leukocyte count (86.73 ± 94.50 cells/mm(3)), mononuclear pleocytosis (lymphocyte percentage of 76.85 ± 15.86), elevated proteins (108.33 ± 52.63 mg%) and normal CSF glucose (64.18 ± 15.92 mg%). We conclude that meningitis is a common and early complication of childhood scrub typhus. The CSF reveals a lymphocytic pleocytosis, raised proteins and a normal glucose level. These children respond promptly to appropriate antibiotics as do children without meningitis. © The Author [2016]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Scrub Typhus: An Emerging Threat
Chakraborty, Sayantani; Sarma, Nilendu
2017-01-01
Scrub typhus is caused by Orientia tsutsugamushi (formerly Rickettsia) and is transmitted to humans by an arthropod vector of the Trombiculidae family (Leptotrombidium deliense and L. akamushi). It is the most common re-emerging Rickettsial infection in India and many other South East Asian countries. In fact, scrub typhus is confined geographically to the Asia Pacific region, a billion people are at risk and nearly a million cases are reported every year. Scrub typhus appears particularly to be distributed in the tsutsugamushi triangle which is distributed over a very wide area of 13 million km2 bound by Japan in the east, through China, the Philippines, tropical Australia in the south, and west through India, Pakistan, possibly to Tibet to Afghanistan, and southern parts of the USSR in the north. Eschar is the characteristic lesion that starts as a vesicular lesion at the site of mite feeding. Later, an ulcer forms with black necrotic center and an erythematous border along with regional lymphadenopathy. Other features are fever, maculopapular rash starting from the trunk, and spreading to the limbs. It may affect the central nervous system, cardiovascular system, renal, respiratory, and gastrointestinal systems. Serious complication in the form of myocarditis, pneumonia, meningoencephalitis, acute renal failure, gastrointestinal bleeding, and even acute respiratory distress syndrome may develop. Tetracycline or chloramphenicol remains the main stay of therapy. PMID:28979009
Gupta, Nitin; Chaudhry, Rama; Kabra, Sushil K; Lodha, Rakesh; Mirdha, Bijay Ranjan; Das, Bimal Kumar; Dey, Aparajit Ballay; Sreenivas, Vishnubhatla
2017-03-24
The major brunt of scrub typhus is borne by developing countries like India but the disease remains neglected. The rapid progression of this infection to serious complications and associated mortality calls for improved diagnostics. The immunoglobulin (Ig)M immunofluorescence assay (IFA), with all of its limitations remains the gold standard. Of 218 suspected cases from patients enrolled in a 2-year study, 30 cases of scrub typhus were detected by IgM IFA, using a 1:64 dilution. The sensitivities of the IgM enzyme-linked immunosorbent assay, IgM rapid flow assay (RFA), and IgG RFA were found to be 97%, 87%, and 77%, respectively. Their respective specificities were 100%, 100%, and 92%, respectively. The sensitivity and specificity of a nested PCR assay targeting a gene encoding a 56-kDa protein were found to be 50% and 100%, respectively.
Smadel, Joseph E.; Rights, Fred L.; Jackson, Elizabeth B.
1946-01-01
A complement-fixing antigen specific for scrub typhus occurs in the body fluids and tissues of infected mice, white rats, and cotton rats. The specific serological substance is demonstrable only in those animals which develop a rapidly fatal disease after an incubation period of a few days. Such an experimental infection is induced in mice and rats by the intravenous injection of suspensions of yolk sac rich in R. orientalis. Ether extraction is an important step in the preparation of a complement-fixing antigen from tissues of mice dying with scrub typhus. The Imphal No. 8 and Calcutta strains of R. orientalis are indistinguishable on the basis of complement fixation and cross-immunity tests. The complement-fixing antigen in body fluids of infected mice and rats and in our preparations of tissues from such animals occurs as a soluble antigen. Under the proper conditions the soluble antigen can be stored or dehydrated without loss of serological activity. PMID:19871518
Sacral Herpes Zoster Associated with Voiding Dysfunction in a Young Patient with Scrub Typhus.
Hur, Jian
2015-06-01
When a patient presents with acute voiding dysfunction without a typical skin rash, it may be difficult to make a diagnosis of herpes zoster. Here, we present a case of scrub typhus in a 25-year-old man with the complication of urinary dysfunction. The patient complained of loss of urinary voiding sensation and constipation. After eight days, he had typical herpes zoster eruptions on the sacral dermatomes and hypalgesia of the S1-S5 dermatomes. No cases of dual infection with varicella zoster virus and Orientia tsutsugamushi were found in the literature. In the described case, scrub typhus probably induced sufficient stress to reactivate the varicella zoster virus. Early recognition of this problem is imperative for prompt and appropriate management, as misdiagnosis can lead to long-term urinary dysfunction. It is important that a diagnosis of herpes zoster be considered, especially in patients with sudden onset urinary retention.
Sacral Herpes Zoster Associated with Voiding Dysfunction in a Young Patient with Scrub Typhus
2015-01-01
When a patient presents with acute voiding dysfunction without a typical skin rash, it may be difficult to make a diagnosis of herpes zoster. Here, we present a case of scrub typhus in a 25-year-old man with the complication of urinary dysfunction. The patient complained of loss of urinary voiding sensation and constipation. After eight days, he had typical herpes zoster eruptions on the sacral dermatomes and hypalgesia of the S1-S5 dermatomes. No cases of dual infection with varicella zoster virus and Orientia tsutsugamushi were found in the literature. In the described case, scrub typhus probably induced sufficient stress to reactivate the varicella zoster virus. Early recognition of this problem is imperative for prompt and appropriate management, as misdiagnosis can lead to long-term urinary dysfunction. It is important that a diagnosis of herpes zoster be considered, especially in patients with sudden onset urinary retention. PMID:26157595
Frances, S P; Watcharapichat, P; Phulsuksombati, D; Tanskul, P
2001-12-01
Monthly collections of rodents were conducted in Phitsanulok Province, central Thailand in 1993 to investigate the role of the mite Blankaartia acuscurellaris as a vector of scrub typhus. Overall, a total of 41 rodents were collected and examined for the presence of the red colored larvae of B. acuscutellaris and yellow larvae of Leptotrombidium deliense and Ascoshoengastia sp. A total of 787 B. acuscutellaris and 1390 yellow larvae were placed into pools, triturated and isolation of Orientia tsutsugamushi attempted in laboratory mice. The sera of 8 of the collected rodents had elevated antibodies to O. tsutsugamushi indicating active infections; however, O. tsutsugamushi was not isolated from rodent tissues or pools of larvae. The results of this survey suggest that B. acuscutellaris may not be an important vector of scrub typhus, but more studies are needed in endemic areas.
Chao, Chien-Chung; Zhangm, Zhiwen; Weissenberger, Giulia; Chen, Hua-Wei; Ching, Wei-Mei
2017-03-01
Scrub typhus (ST) is an infection caused by Orientia tsutsugamushi. Historically, ST was ranked as the second most important arthropod-borne medical problem only behind malaria during World War II and the Vietnam War. The disease occurs mainly in Southeast Asia and has been shown to emerge and reemerge in new areas, implying the increased risk for U.S. military and civilian personnel deployed to these regions. ST can effectively be treated by doxycycline provided the diagnosis is made early, before the development of severe complications. Scrub Typhus Detect is a lateral flow rapid test based on a mixture of recombinant 56-kDa antigens with broad reactivity. The performance of this prototype product was evaluated against indirect immunofluorescence assay, the serological gold standard. Using 249 prospectively collected samples from Thailand, the sensitivity and specificity for IgM was found to be 100% and 92%, respectively, suggesting a high potential of this product for clinical use. This product will provide a user friendly, rapid, and accurate diagnosis of ST for clinicians to provide timely and accurate treatments of deployed personnel. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.
Kim, Gwanghun; Ha, Na-Young; Min, Chan-Ki; Kim, Hong-Il; Yen, Nguyen Thi Hai; Lee, Keun-Hwa; Oh, Inbo; Kang, Jae-Seung; Choi, Myung-Sik; Kim, Ik-Sang
2017-01-01
Background Scrub typhus is a mite-borne febrile disease caused by O. tsutsugamushi infection. Recently, emergence of scrub typhus has attracted considerable attention in several endemic countries in Asia and the western Pacific. In addition, the antigenic diversity of the intracellular pathogen has been a serious obstacle for developing effective diagnostics and vaccine. Methodology/Principal findings To understand the evolutionary pathway of genotypic diversification of O. tsutsugamushi and the environmental factors associated with the epidemiological features of scrub typhus, we analyzed sequence data, including spatiotemporal information, of the tsa56 gene encoding a major outer membrane protein responsible for antigenic variation. A total of 324 tsa56 sequences covering more than 85% of its open reading frame were analyzed and classified into 17 genotypes based on phylogenetic relationship. Extensive sequence analysis of tsa56 genes using diverse informatics tools revealed multiple intragenic recombination events, as well as a substantially higher mutation rate than other house-keeping genes. This suggests that genetic diversification occurred via frequent point mutations and subsequent genetic recombination. Interestingly, more diverse bacterial genotypes and dominant vector species prevail in Taiwan compared to other endemic regions. Furthermore, the co-presence of identical and sub-identical clones of tsa56 gene in geographically distant areas implies potential spread of O. tsutsugamushi genotypes. Conclusions/Significance Fluctuation and diversification of vector species harboring O. tsutsugamushi in local endemic areas may facilitate genetic recombination among diverse genotypes. Therefore, careful monitoring of dominant vector species, as well as the prevalence of O. tsutsugamushi genotypes may be advisable to enable proper anticipation of epidemiological changes of scrub typhus. PMID:28248956
An outbreak investigation of scrub typhus in Western Province, Solomon Islands, 2014.
Marks, Michael; Joshua, Cynthia; Longbottom, Jenny; Longbottom, Katherine; Sio, Alison; Puiahi, Elliot; Jilini, Greg; Stenos, John; Dalipanda, Tenneth; Musto, Jennie
2016-01-01
To identify the etiology and risk factors of undifferentiated fever in a cluster of patients in Western Province, Solomon Islands, May 2014. An outbreak investigation with a case control study was conducted. A case was defined as an inpatient in one hospital in Western Province, Solomon Islands with high fever (> 38.5 °C) and a negative malaria microscopy test admitted between 1 and 31 May 2014. Asymptomatic controls matched with the cases residentially were recruited in a ratio of 1:2. Serum samples from the subjects were tested for rickettsial infections using indirect micro-immunofluorescence assay. Nine cases met the outbreak case definition. All cases were male. An eschar was noted in five cases (55%), and one developed pneumonitis. We did not identify any environmental factors associated with illness. Serum samples of all five follow-up cases (100%) had strong-positive IgG responses to scrub typhus. All but one control (10%) had a moderate response against scrub typhus. Four controls had low levels of antibodies against spotted fever group rickettsia, and only one had a low-level response to typhus group rickettsia. This outbreak represents the first laboratory-confirmed outbreak of scrub typhus in the Western Province of Solomon Islands. The results suggest that rickettsial infections are more common than currently recognized as a cause of an acute febrile illness. A revised clinical case definition for rickettsial infections and treatment guidelines were developed and shared with provincial health staff for better surveillance and response to future outbreaks of a similar kind.
Chang, Po-Hsiung; Cheng, Yu-Pin; Chang, Po-Sheng; Lo, Chiao-Wei; Lin, Lung-Huang; Lu, Chin-Fang; Chung, Wen-Hung
2018-04-24
Scrub typhus is becoming a clinically important cause of acute undifferentiated febrile illness in Taiwan. The incubation period is between 6 and 21 days after exposure. It is transmitted by chiggers (larva of trombiculid mite) in long grasses and in dirt-floor homes, with infection characterized by a flu-like illness of fever, headache, and myalgia lasting approximately 1 week. It has various systemic manifestations, including GI symptoms. In some, the illness progresses to multiorgan dysfunction syndrome and death. We report on a 13-year-old boy who lived in Taipei City and who had initially tentative diagnosis of acute pyrexia of unknown origin with high fever up to 40.3°C for 1 week, but later had thrombocytopenia and diffuse abdominal pain with peritoneal sign suspected acute appendicitis. During the clinical course, septic shock and disseminated intravascular coagulopathy (DIC) were noted. There were skin rash in his trunk and extremities and an eschar with black crust surrounded by a scaling erythematous rim on his right buttock. In addition, we got the information of his travel history in Green Island and Orchid Island for 10 days.With the correct antibiotics, vancomycin, meropenem, and doxycycline, the patient was getting better and corresponding with high level of granulysin and tumor necrosis factor-alpha. The diagnosis of scrub typhus was confirmed by the biopsy of eschar and high quantitative real-time polymerase chain reaction values of Orientia tsutsugamushi (16sRNA and 56 kDa) tested by Centers for Disease Control and Prevention, Taiwan. Histopathological findings of the eschar revealed the leukocytoclastic vasculitis, crust and thrombus formation with many gram-negative microorganisms, O. tsutsugamushi demonstrated by 47 kDa monoclonal antibody immunohistochemical stain and electromicroscopy. After the careful selection of appropriate antibiotics including meropenem, vancomycin, and doxycycline, he recovered and was subsequently discharged 7 days after admission. This case highlights that scrub typhus infection can mimic acute abdomen and septic shock with DIC. This rare presentation of acute abdomen and septic shock with thrombocytopenia and DIC caused by scrub typhus should remind physicians to be alert to the possibility of acute abdomen and febrile illness resulting from scrub typhus.
Kollars, T M; Kengluecha, A; Khlaimanee, N; Tanskul, P
2001-01-01
Eggs from seven colony lines of the chigger mite Leptotrombidium imphalum (Vercammen-Grandjean & Langston) were examined for infection with Orientia tsutsugamushi (Hyashi), the etiologic agent of scrub typhus. The polymerase chain reaction (PCR) using primers OtP 56.809 and OtM 56.1221, which amplify a 291 bp region of the P56 gene of O. tsutsugamushi, was used to detect scrub typhus within single eggs. All seven chigger mite lines produced infected eggs with varying rates of infection (Li1 = 8.1%, n = 124; Li2 = 45.6%, n = 90; Li3 = 30.1%, n = 144; Li4 = 31.7%, n = 145; Li5 = 21.3%, n = 136; Li6 = 41.6% n = 77; Li7 = 22.5%, n = 110). The 3 wk with the highest infection rates for each line using Fourier analysis were as follows: Li1 = 2, 7, 14; Li2 = 4, 6, 12; Li3 = 3, 6, 12; Li4 = 4, 6, 12; Li5 = 5, 7, 14; Li7 = 4, 6, 12. Li6 only had nine measurements over time; therefore, Li6 was excluded from individual analysis. Infection rates of scrub typhus in eggs occurred in a 2-wk 2-d cycle, using Fourier analysis of combined data. Not only did infection rates vary among the progeny of females, but temporal variation also occurred.
Typhus-like Fevers of Unknown Ætiology, with Special Reference to the Malay States
Fletcher, William
1930-01-01
Typhus exanthematicus, Rocky Mountain fever, and the tsutsugamushi disease have been classified in the “typhus group” by Megaw, as louse-typhus, tick-typhus, and mite-typhus. He has added a fourth-class, comprising typhus-like fevers, with unknown vectors. It is the diseases of this class with which this paper is concerned. Endemic typhus (Brill's disease) is very closely related to typhus fever; the Weil-Felix reaction is positive, typhus-like vascular lesions are present, and there is cross-immunity with typhus. In the exanthematic fever of Marseilles the relationship is more superficial; there is neither cross-immunity nor vascular lesion, and the Weil-Felix reaction is negative. Some, e.g., the scrub-typhus of Malaya (vector probably a mite), are more nearly related to tsutsugamushi than to typhus; others, e.g., Indian “tick-typhus” (vector probably a tick), to Rocky Mountain fever. All are non-contagious, non-epidemic, warm-weather diseases. They are unassociated with dirt, squalor, or lice, and are restricted to definite foci. Probably rodents or other animals are the reservoirs of the virus. On the question of identity with typhus, health authorities decide that notification is unnecessary; typhus introduced into America spreads, Brill's disease does not. These typhus-like diseases are not the same in all the countries where they occur. There are two main groups: (1) an urban group, more closely related to typhus, in which the Weil-Felix reaction is positive; (2) a rural group, more closely related to tsutsugamushi and Rocky Mountain fever, in which the Weil-Felix reaction is negative. There is a special non-indologenic strain of B. proteus, which is agglutinated in some of the fevers belonging to the second group. Tropical typhus in the Malay States: (1) urban form, or “shop-typhus,” resembling Brill's disease; (2) rural form or “scrub-typhus.” Peculiar association with oil-palms and coarse grass. PMID:19987538
Acute undifferentiated fever in India: a multicentre study of aetiology and diagnostic accuracy.
Mørch, Kristine; Manoharan, Anand; Chandy, Sara; Chacko, Novin; Alvarez-Uria, Gerardo; Patil, Suvarna; Henry, Anil; Nesaraj, Joel; Kuriakose, Cijoy; Singh, Ashita; Kurian, Siby; Gill Haanshuus, Christel; Langeland, Nina; Blomberg, Bjørn; Vasanthan Antony, George; Mathai, Dilip
2017-10-04
The objectives of this study were to determine the proportion of malaria, bacteraemia, scrub typhus, leptospirosis, chikungunya and dengue among hospitalized patients with acute undifferentiated fever in India, and to describe the performance of standard diagnostic methods. During April 2011-November 2012, 1564 patients aged ≥5 years with febrile illness for 2-14 days were consecutively included in an observational study at seven community hospitals in six states in India. Malaria microscopy, blood culture, Dengue rapid NS1 antigen and IgM Combo test, Leptospira IgM ELISA, Scrub typhus IgM ELISA and Chikungunya IgM ELISA were routinely performed at the hospitals. Second line testing, Dengue IgM capture ELISA (MAC-ELISA), Scrub typhus immunofluorescence (IFA), Leptospira Microscopic Agglutination Test (MAT), malaria PCR and malaria immunochromatographic rapid diagnostic test (RDT) Parahit Total™ were performed at the coordinating centre. Convalescence samples were not available. Case definitions were as follows: Leptospirosis: Positive ELISA and positive MAT. Scrub typhus: Positive ELISA and positive IFA. Dengue: Positive RDT and/or positive MAC-ELISA. Chikungunya: Positive ELISA. Bacteraemia: Growth in blood culture excluding those defined as contaminants. Malaria: Positive genus-specific PCR. Malaria was diagnosed in 17% (268/1564) and among these 54% had P. falciparum. Dengue was diagnosed in 16% (244/1564). Bacteraemia was found in 8% (124/1564), and among these Salmonella typhi or S. paratyphi constituted 35%. Scrub typhus was diagnosed in 10%, leptospirosis in 7% and chikungunya in 6%. Fulfilling more than one case definition was common, most frequent in chikungunya where 26% (25/98) also had positive dengue test. Malaria and dengue were the most common causes of fever in this study. A high overlap between case definitions probably reflects high prevalence of prior infections, cross reactivity and subclinical infections, rather than high prevalence of coinfections. Low accuracy of routine diagnostic tests should be taken into consideration when approaching the patient with acute undifferentiated fever in India.
Chen, Hongliu; Ning, Zong; Qiu, Ying; Liao, Yuanli; Chang, Haihua; Ai, Yuanyuan; Wei, Yinghua; Deng, Yiming; Shen, Ying
2017-08-01
This study aimed to investigate whether von Willebrand factor (vWF) and high mobility group box 1 (HMGB1) are associated with the severity and clinical outcome of scrub typhus and to seek novel biomarkers for surveillance and prediction of the prognosis of this infection. Serum concentrations of vWF and HMGB1 were measured twice by ELISA for scrub typhus patients (n=103), once prior to doxycycline therapy and then on day 7 of doxycycline therapy; concentrations were measured once for healthy controls (n=32). Among the total 103 patients enrolled, 38 had disease complicated by multiple organ dysfunction syndrome (MODS). Serum concentrations of vWF and HMGB1 were significantly higher in all the patients than in the healthy controls, both prior to doxycycline treatment and on day 7 of doxycycline treatment (p<0.01). Furthermore, serum levels of vWF, HMGB1, and creatinine (SCr) in the patients with MODS increased distinctly, while the platelet (PLT) count diminished markedly compared to the levels in patients without MODS (p<0.01). The concentration of vWF was positively correlated with that of HMGB1 (r=0.764, p<0.001) and SCr (r=0.528, p<0.001), but negatively correlated with the PLT count (r=-0.632, p<0.001). Both HMGB1 and vWF were significantly associated with mortality in scrub typhus (area under the curve (AUC)=0.864, p=0.001, and AUC=0.862, p=0.001, respectively). Elevated levels of vWF and HMGB1 are associated with the severity and clinical outcome of scrub typhus. These represent possible new biomarkers for use in the assessment and prognostic prediction of this infection. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Clinical profile and improving mortality trend of scrub typhus in South India.
Varghese, George M; Trowbridge, Paul; Janardhanan, Jeshina; Thomas, Kurien; Peter, John V; Mathews, Prasad; Abraham, Ooriapadickal C; Kavitha, M L
2014-06-01
Scrub typhus, a bacterial zoonosis caused by Orientia tsutsugamushi, may cause multiorgan dysfunction syndrome (MODS) and is associated with significant mortality. This study was undertaken to document the clinical and laboratory manifestations and complications and to study time trends and factors associated with mortality in patients with scrub typhus infection. This retrospective study, done at a university teaching hospital, included 623 patients admitted between 2005 and 2010 with scrub typhus. The diagnosis was established by a positive IgM ELISA and/or pathognomonic eschar with PCR confirmation where feasible. The clinical and laboratory profile, course in hospital, and outcome were documented. Factors associated with mortality were analyzed using multivariate logistic regression analysis. The most common presenting symptoms were fever (100%), nausea/vomiting (54%), shortness of breath (49%), headache (46%), cough (38%), and altered sensorium (26%). An eschar was present in 43.5% of patients. Common laboratory findings included elevated transaminases (87%), thrombocytopenia (79%), and leukocytosis (46%). MODS was seen in 34% of patients. The overall case-fatality rate was 9.0%. Features of acute lung injury were observed in 33.7%, and 29.5% required ventilatory support. On multivariate analysis, shock requiring vasoactive agents (relative risk (RR) 10.5, 95% confidence interval (CI) 4.2-25.7, p<0.001), central nervous system (CNS) dysfunction (RR 5.1, 95% CI 2.4-10.7, p<0.001), and renal failure (RR 3.6, 95% CI 1.7-7.5, p=0.001) were independent predictors of mortality. Over 4 years, a decreasing trend was observed in the mortality rate. Scrub typhus can manifest with potentially life-threatening complications such as lung injury, shock, and meningoencephalitis. MODS occurred in a third of our patients. The overall case-fatality rate was 9%, with shock, renal failure, and CNS associated with a higher mortality. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Thipmontree, Wilawan; Tantibhedhyangkul, Wiwit; Silpasakorn, Saowaluk; Wongsawat, Ekkarat; Waywa, Duangdao; Suputtamongkol, Yupin
2016-10-05
Scrub typhus is endemic in Thailand. Of the 495 patients with acute undifferentiated fever studied in Maharat Nakhon Ratchasima Hospital, Nakhon Ratchasima, Thailand, from June 1, 2011, to December 31, 2012, 146 patients (29.5%) had confirmed scrub typhus. The majority of cases were male, farmers, with the mean (±standard deviation) age of 54.1 ± 15.2 years. A total of 59 patients (40.4%) had eschar lesion. The commonest sites for an eschar in male patients were the perineum, inguinal, and buttock area; whereas in females, it was the head and neck area. Abnormal electrocardiogram was found in 39 of 79 patients (49.4%) with sinus tachycardia being the most frequent finding (17, 21.5%). A total of 73 patients (50%) had at least one complication. Myocarditis was the cause of complete heart block in a scrub typhus patient, and he fully recovered after receiving intravenous chloramphenicol treatment. The case fatality rate was 6.2% (nine deaths).The independent predictors for fatal outcome were age over 65 years (odds ratio [OR] = 14.49, 95% confidence interval [CI] = 1.26-166.44, P = 0.03), acute kidney injury (OR = 12.75, 95% CI = 1.77-92.07, P = 0.01), and hyperbilirubinemia (OR = 24.82, 95% CI = 2.12-286.61, P = 0.01). Early diagnosis and prompt appropriate treatment can improve the patient's outcome. © The American Society of Tropical Medicine and Hygiene.
Varghese, George M; Janardhanan, Jeshina; Trowbridge, Paul; Peter, John V; Prakash, John A J; Sathyendra, Sowmya; Thomas, Kurien; David, Thambu S; Kavitha, M L; Abraham, Ooriapadickal C; Mathai, Dilip
2013-11-01
This study sought to document the clinical and laboratory manifestations, genetic variability, and outcomes of scrub typhus, an often severe infection caused by Orientia tsutsugamushi, in South India. Patients admitted to a large teaching hospital with IgM ELISA-confirmed scrub typhus were evaluated. Clinical examination with a thorough search for an eschar, laboratory testing, chest X-ray, and outcome were documented and analyzed. Additionally, a 410-bp region of the 56-kDa type-specific antigen gene of O. tsutsugamushi was sequenced and compared with isolates from other regions of Asia. Most of the 154 patients evaluated presented with fever and non-specific symptoms. An eschar was found in 86 (55%) patients. Mild hepatic involvement was seen in most, with other organ involvement including respiratory, cardiovascular, and renal. Multi-organ dysfunction was noted in 59 (38.3%), and the fatality rate was 7.8%. Hypotension requiring vasoactive agents was found to be an independent predictor of mortality (p<0.001). The phylogeny of 26 samples showed 17 (65%) clustering with the Kato-like group and eight (31%) with the Karp-like group. The presentation of scrub typhus can be variable, often non-specific, but with potentially severe multi-organ dysfunction. Prompt recognition is key to specific treatment and good outcomes. Further study of the circulating strains is essential for the development of a successful vaccine and sensitive point-of-care testing. Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Otterdal, Kari; Janardhanan, Jeshina; Astrup, Elisabeth; Ueland, Thor; Prakash, John A J; Lekva, Tove; Abraham, O C; Thomas, Kurien; Damås, Jan Kristian; Mathews, Prasad; Mathai, Dilip; Aukrust, Pål; Varghese, George M
2014-11-01
Scrub typhus is endemic in the Asia-Pacific region. Mortality is high even with treatment, and further knowledge of the immune response during this infection is needed. This study was aimed at comparing plasma levels of monocyte/macrophage and endothelial related inflammatory markers in patients and controls in South India and to explore a possible correlation to disease severity and clinical outcome. Plasma levels of ALCAM, VCAM-1, sCD163, sCD14, YKL-40 and MIF were measured in scrub typhus patients (n = 129), healthy controls (n = 31) and in infectious disease controls (n = 31), both in the acute phase and after recovery, by enzyme immunoassays. Patients had markedly elevated levels of all mediators in the acute phase, differing from both healthy and infectious disease controls. During follow-up levels of ALCAM, VCAM-1, sCD14 and YKL-40 remained elevated compared to levels in healthy controls. High plasma ALCAM, VCAM-1, sCD163, sCD14, and MIF, and in particular YKL-40 were all associated with disease severity and ALCAM, sCD163, MIF and especially YKL-40, were associated with mortality. Our findings show that scrub typhus is characterized by elevated levels of monocyte/macrophage and endothelial related markers. These inflammatory markers, and in particular YKL-40, may contribute to disease severity and clinical outcome. Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
Kalra, Varun; Ahmad, Sohaib; Shrivastava, Vikas; Mittal, Garima
2016-05-01
A single diagnostic test for acute undifferentiated febrile illnesses (AUFI) is elusive. This pilot study was undertaken on the premise that leucocytes, being the main cells of defence, undergo quantitative, structural and functional changes in AUFI. We evaluated the potential of volume, conductivity and scatter (VCS) parameters of leucocytes, generated with the haemogram report by the Coulter auto-analyzer, in differentiating the common etiologies of AUFI. The haematological and VCS data obtained from 800 controls and 200 cases of AUFI (50 cases each of acute malaria, dengue, scrub typhus and enteric fever) were retrieved for analysis. The cases and controls differed significantly with respect to relative numbers and the VCS parameters of neutrophils, lymphocytes and monocytes (p<0.05). The neutrophil and lymphocyte were significantly voluminous in acute malaria and scrub typhus as compared to dengue and enteric fevers (p<0.05). Enteric fever significantly enhanced the conductivity of neutrophils as compared to other subgroups while lymphocyte conductivity significantly differed from dengue and scrub typhus. Lymphocyte and neutrophil scatter values in malaria and scrub typhus were comparable but differed significantly from that in enteric fever. Etiology-specific changes occur in leucocytes, both in numbers and their VCS properties which can be identified without additional cost. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Problem Oriented Differential Diagnosis of Tropical Diseases
1989-09-01
glomerulonephritis. 13. Varicella ( chicken pox ): rare complication. II. Nephrotic syndrome A distinctive lesion associated with nephrotic syndrome in West...hypersensitivity reactions, Stevens-Johnson syndrome, toxic nephrosis, and hypoglycemia. Studies in Mexico have shown that bismuth subsalicylate tablets are...typhus fever 7 14 Murine typhus 14 26 Q fever 10 21 Rickettsial pox 3 14 Rocky mountain spotted fever 6 21 Scrub typhus 2 10 Tick-borne rickettsioses
Ching, W.-M.; Rowland, D.; Zhang, Z.; Bourgeois, A. L.; Kelly, D.; Dasch, G. A.; Devine, P. L.
2001-01-01
The variable 56-kDa major outer membrane protein of Orientia tsutsugamushi is the immunodominant antigen in human scrub typhus infections. We developed a rapid immunochromatographic flow assay (RFA) for the detection of immunoglobulin M (IgM) and IgG antibodies to O. tsutsugamushi. The RFA employs a truncated recombinant 56-kDa protein from the Karp strain as the antigen. The performance of the RFA was evaluated with a panel of 321 sera (serial bleedings of 85 individuals suspected of scrub typhus) which were collected in the Pescadore Islands, Taiwan, from 1976 to 1977. Among these 85 individuals, IgM tests were negative for 7 cases by both RFA and indirect fluorescence assay (IFA) using Karp whole-cell antigen. In 29 cases specific responses were detected by the RFA earlier than by IFA, 44 cases had the same detection time, and 5 cases were detected earlier by IFA than by RFA. For IgG responses, 4 individuals were negative with both methods, 37 cases exhibited earlier detection by RFA than IFA, 42 cases were detected at the same time, and 2 cases were detected earlier by IFA than by RFA. The sensitivities of RFA detection of antibody in sera from confirmed cases were 74 and 86% for IgM and IgG, respectively. When IgM and IgG results were combined, the sensitivity was 89%. A panel of 78 individual sera collected from patients with no evidence of scrub typhus was used to evaluate the specificity of the RFA. The specificities of the RFA were 99% for IgM and 97% for IgG. The sensitivities of IFA were 53 and 73% for IgM and IgG, respectively, and were 78% when the results of IgM and IgG were combined. The RFA test was significantly better than the IFA test for the early detection of antibody to scrub typhus in primary infections, while both tests were equally sensitive with reinfected individuals. PMID:11238230
Approaches to vaccines against Orientia tsutsugamushi.
Valbuena, Gustavo; Walker, David H
2012-01-01
Scrub typhus is a severe mite-borne infection caused by Orientia tsutsugamushi, an obligately intracellular bacterium closely related to Rickettsia. The disease explains a substantial proportion of acute undifferentiated febrile cases that require hospitalization in rural areas of Asia, the North of Australia, and many islands of the Pacific Ocean. Delayed antibiotic treatment is common due to the lack of effective commercially available diagnostic tests and the lack of specificity of the early clinical presentation. The systemic infection of endothelial cells that line the vasculature with Orientia can lead to many complications and fatalities. In survivors, immunity does not last long, and is poorly cross-reactive among numerous strains. In addition, chronic infections are established in an unknown number of patients. All those characteristics justify the pursuit of a prophylactic vaccine against O. tsutsugamushi; however, despite continuous efforts to develop such a vaccine since World War II, the objective has not been attained. In this review, we discuss the history of vaccine development against Orientia to provide a clear picture of the challenges that we continue to face from the perspective of animal models and the immunological challenges posed by an intracellular bacterium that normally triggers a short-lived immune response. We finish with a proposal for development of an effective and safe vaccine for scrub typhus through a new approach with a strong focus on T cell-mediated immunity, empirical testing of the immunogenicity of proteins encoded by conserved genes, and assessment of protection in relevant animal models that truly mimic human scrub typhus.
Approaches to vaccines against Orientia tsutsugamushi
Valbuena, Gustavo; Walker, David H.
2013-01-01
Scrub typhus is a severe mite-borne infection caused by Orientia tsutsugamushi, an obligately intracellular bacterium closely related to Rickettsia. The disease explains a substantial proportion of acute undifferentiated febrile cases that require hospitalization in rural areas of Asia, the North of Australia, and many islands of the Pacific Ocean. Delayed antibiotic treatment is common due to the lack of effective commercially available diagnostic tests and the lack of specificity of the early clinical presentation. The systemic infection of endothelial cells that line the vasculature with Orientia can lead to many complications and fatalities. In survivors, immunity does not last long, and is poorly cross-reactive among numerous strains. In addition, chronic infections are established in an unknown number of patients. All those characteristics justify the pursuit of a prophylactic vaccine against O. tsutsugamushi; however, despite continuous efforts to develop such a vaccine since World War II, the objective has not been attained. In this review, we discuss the history of vaccine development against Orientia to provide a clear picture of the challenges that we continue to face from the perspective of animal models and the immunological challenges posed by an intracellular bacterium that normally triggers a short-lived immune response. We finish with a proposal for development of an effective and safe vaccine for scrub typhus through a new approach with a strong focus on T cell-mediated immunity, empirical testing of the immunogenicity of proteins encoded by conserved genes, and assessment of protection in relevant animal models that truly mimic human scrub typhus. PMID:23316486
Eamsobhana, Praphathip; Yoolek, Adisak; Kongkaew, Wittaya; Lerdthusnee, Kriangkrai; Khlaimanee, Nittaya; Parsartvit, Anchana; Malainual, Nat; Yong, Hoi-Sen
2009-03-01
Scrub typhus, a rickettsial disease transmitted by several species of Leptotrombidium chiggers (larvae), is endemic in many areas of Asia. The disease is best prevented by the use of personal protective measures, including repellents. In this study commercially produced aromatic, essential oils of 13 plant species and ethanol (control) were tested in the laboratory for repellency against host-seeking chiggers of Leptotrombidium imphalum Vercammen-Grandjean and Langston (Acari: Trombiculidae). A rapid, simple and economic in vitro test method was used by exposing the chigger for up to 5 min. Repellency was based on relative percentages of chiggers attracted to test and control substances. Four of the 13 essential oils showed promise as effective repellent against L. imphalum chiggers. Syzygium aromaticum (clove) oil exhibited 100% repellency at 5% concentration (dilution with absolute ethanol), whereas Melaleuca alternifolia (tea tree) oil exhibited 100% repellency at 40% concentration. Undiluted oils of Zingiber cassamunar (plai) and Eucalyptus globules (blue gum) exhibited 100% repellency. Of the remaining nine essential oils, only 100% Pelargonium graveolens (geranium) exhibited >50% repellency (viz. 57%). Styrax torkinensis (benzoin) oil did not exhibit any repellency. These findings show that several aromatic, essential oils of plants may be useful as chigger repellent for the prevention of scrub typhus. Syzygium aromaticum oil may be safer and more economical to prevent chigger attacks than commercially available synthetic chemicals, such as DEET that may have harmful side effects.
Trung, Nguyen Vu; Hoi, Le Thi; Thuong, Nguyen Thi Hong; Toan, Tran Khanh; Huong, Tran Thi Kieu; Hoa, Tran Mai; Fox, Annette; Kinh, Nguyen van; van Doorn, H Rogier; Wertheim, Heiman F L; Bryant, Juliet E; Nadjm, Behzad
2017-05-01
AbstractRickettsial infections are recognized as important causes of fever throughout southeast Asia. Herein, we determined the seroprevalence to rickettsioses within rural and urban populations of northern Vietnam. Prevalence of individuals with evidence of prior rickettsial infections (IgG positive) was surprisingly low, with 9.14% (83/908) testing positive to the three major rickettsial serogroups thought to circulate in the region. Prevalence of typhus group rickettsiae (TG)-specific antibodies (6.5%, 58/908) was significantly greater than scrub typhus group orientiae (STG)- or spotted fever group rickettsiae (SFG)-specific antibodies ( P < 0.05). The majority of TG seropositives were observed among urban rather than rural residents ( P < 0.05). In contrast, overall antibody prevalence to STG and SFG were both very low (1.1%, 10/908 for STG; 1.7%, 15/908 for SFG), with no significant differences between rural and urban residents. These results provide data on baseline population characteristics that may help inform development of Rickettsia serological testing criteria in future clinical studies.
Le Viet, Nhiem; Laroche, Maureen; Thi Pham, Hoa L; Viet, Nho L; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe
2017-02-01
Scrub typhus is a rickettsiosis which is caused by Orientia tsutsugamushi and occurs throughout the Asia-Pacific region. Molecular diagnosis of rickettsioses using eschar swabs has recently emerged, and may be very useful for the diagnosis of these diseases in tropical settings. Quantitative polymerase chain reaction (qPCR) was used to detect O. tsutsugamushi DNA in whole blood and eschar swab specimens of 67 patients who were clinically suspected of scrub typhus in Quang Nam province, Vietnam. Among the 20 patients for whom both eschar and whole blood were obtained, 17 (85%) of the eschar specimens and 5 (25%) of the whole blood specimens tested positive for O. tsutsugamushi. Genetic analysis of the 56-kDa TSA gene sequences demonstrated that the 14 sequences obtained in this study, including 12 eschar swabs and 2 whole blood specimens, were related to 4 groups: Karp, Kawasaki, Gilliam (JG-v and TG-v) and TA716. The majority (9/14; 64.4%) of contemporary O. tsutsugamushi genotypes in Quang Nam province were related to the Karp group. These results suggest that polyclonal antigen pools used for serological testing in the future should contain at least Karp, Kawasaki, Gilliam and TA716 antigens for Vietnamese patients, as well as patients who have traveled to Vietnam. qPCR after eschar swabbing should be considered for molecular diagnosis of scrub typhus in endemic patients as well as in travelers, since it is easy to perform and appears very useful for the rapid detection of Orientia tsutsugamushi in the early phase of infection.
Frances, S P; Khlaimanee, N
1996-03-01
Laboratory tests were conducted to compare the response of noninfected Leptotrombidium deliense Sambon and Leptotrombidium fletcheri (Womersley & Heaslip) and L. deliense naturally infected with Rickettsia tsutsugamushi, the etiologic agent of scrub typhus, to 8 chemical repellents and toxicants. Low concentrations of permethrin, dimethylphthalate, diethyl methylbenzamide, benzyl benzoate, di-n-propyl 2,5-pyridine-dicarboxylate, 1-(3-Cyclohexen-1-yl-carbonyl)-2-methylpiperidine (AI3-37220), 2-hydroxymethyl-cyclohexyl acetic acid lactone, and a high concentration of dibutylphthalate (DBP) were toxic for noninfected larvae of both species tested. The median effective knockdown time for all chemicals, except 1% AI3-37220 and 5% permethrin, were longer against infected L. deliense than uninfected larvae of the same species. However, the results indicate that low concentrations of all chemicals, except DBP, should be effective against 2 important vectors of scrub typhus.
Revisiting doxycycline in pregnancy and early childhood--time to rebuild its reputation?
Cross, Ruby; Ling, Clare; Day, Nicholas P J; McGready, Rose; Paris, Daniel H
2016-01-01
Doxycycline is highly effective, inexpensive with a broad therapeutic spectrum and exceptional bioavailability. However these benefits have been overshadowed by its classification alongside the tetracyclines - class D drugs, contraindicated in pregnancy and in children under 8 years of age. Doxycycline-treatable diseases are emerging as leading causes of undifferentiated febrile illness in Southeast Asia. For example scrub typhus and murine typhus have an unusually severe impact on pregnancy outcomes, and current mortality rates for scrub typhus reach 12-13% in India and Thailand. The emerging evidence for these important doxycycline-treatable diseases prompted us to revisit doxycycline usage in pregnancy and childhood. A systematic review of the available literature on doxycycline use in pregnant women and children revealed a safety profile of doxycycline that differed significantly from that of tetracycline; no correlation between the use of doxycycline and teratogenic effects during pregnancy or dental staining in children was found. The change of the US FDA pregnancy classification scheme to an evidence-based approach will enable adequate evaluation of doxycycline in common tropical illnesses and in vulnerable populations in clinical treatment trials, dosage-optimization pharmacokinetic studies and for the empirical treatment of undifferentiated febrile illnesses, especially in pregnant women and children.
Chigger (Acarina:Trombiculidae) surveys of the west coast beaches of Sabah and Sarawak.
Dohany, A L; Phang, O W; Rapmund, G
1977-06-01
Leptotrombidium (Leptotrombidium) arenicola Traub, a vector of scrub typhus, had previously been found to occur in the coastal vegetation behind the edge of open sand along the beaches of Peninsular Malaysia. Surveys of the west coast beaches of Sabah and Sarawak were conducted to determine if this species occurs in similar habitat in East Malaysia on the island of Borneo. Leptotrombidium (L.) arenicola was not collected from the eighteen sites studied. Of the 11,982 mite larvae collected, 55 per cent were L.(L.) deliense (Walch), a well-known, widespread vector of scrub typhus.
Kalal, B S; Puranik, P; Nagaraj, S; Rego, S; Shet, A
2016-01-01
Rickettsial infections are re-emerging. In India, they are now being reported from several areas where they were previously unknown. The objective of this study was to describe the epidemiology, clinical profile and outcome of serologically-confirmed scrub typhus and spotted fever among children in a tertiary care hospital in Bengaluru. Hospitalised children aged <18 years, with clinical features suggestive of rickettsial disease admitted between January 2010 and October 2012 were included prospectively. Diagnosis was based on scrub typhus and spotted fever-specific IgM and IgG by enzyme-linked immunosorbent assay (ELISA). Of 103 children with clinical features suggestive of rickettsial illness, ELISA test confirmed 53 cases for scrub typhus, 23 cases for spotted fever group and 14 with mixed infection. The average age was 7.3 (±3.9) years and 44 (71.0%) children were male. Majority of cases were from Karnataka (50%), Andhra Pradesh (32.3%) and Tamil Nadu (17.7%). Common clinical features included fever (100%, average duration 11 days), nausea and vomiting (44%), rash (36%); eschar was rare. Compared to the ELISA test, Weil-Felix test (OX-K titre of 1:80) had a sensitivity and specificity of 88.7% and 43.9%, respectively. Treatment with chloramphenicol or doxycycline was given to the majority of the children. Complications included meningoencephalitis (28%), shock (10%), retinal vasculitis (10%) and purpura fulminans (7%). These findings suggest that the burden of rickettsial infection among children in India is high, with a substantially high complication rate. Rickettsial-specific ELISA tests can help in early diagnosis and early institution of appropriate treatment that may prevent life-threatening complications.
Le Viet, Nhiem; Laroche, Maureen; Thi Pham, Hoa L.; Viet, Nho L.; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe
2017-01-01
Background Scrub typhus is a rickettsiosis which is caused by Orientia tsutsugamushi and occurs throughout the Asia-Pacific region. Molecular diagnosis of rickettsioses using eschar swabs has recently emerged, and may be very useful for the diagnosis of these diseases in tropical settings. Methodology/Principal findings Quantitative polymerase chain reaction (qPCR) was used to detect O. tsutsugamushi DNA in whole blood and eschar swab specimens of 67 patients who were clinically suspected of scrub typhus in Quang Nam province, Vietnam. Among the 20 patients for whom both eschar and whole blood were obtained, 17 (85%) of the eschar specimens and 5 (25%) of the whole blood specimens tested positive for O. tsutsugamushi. Genetic analysis of the 56-kDa TSA gene sequences demonstrated that the 14 sequences obtained in this study, including 12 eschar swabs and 2 whole blood specimens, were related to 4 groups: Karp, Kawasaki, Gilliam (JG-v and TG-v) and TA716. The majority (9/14; 64.4%) of contemporary O. tsutsugamushi genotypes in Quang Nam province were related to the Karp group. Conclusions These results suggest that polyclonal antigen pools used for serological testing in the future should contain at least Karp, Kawasaki, Gilliam and TA716 antigens for Vietnamese patients, as well as patients who have traveled to Vietnam. qPCR after eschar swabbing should be considered for molecular diagnosis of scrub typhus in endemic patients as well as in travelers, since it is easy to perform and appears very useful for the rapid detection of Orientia tsutsugamushi in the early phase of infection. PMID:28241043
Trung, Nguyen vu; Hoi, Le Thi; Thuong, Nguyen Thi Hong; Toan, Tran Khanh; Huong, Tran Thi Kieu; Hoa, Tran Mai; Fox, Annette; van Kinh, Nguyen; van Doorn, H. Rogier; Wertheim, Heiman F. L.; Bryant, Juliet E.; Nadjm, Behzad
2017-01-01
Rickettsial infections are recognized as important causes of fever throughout southeast Asia. Herein, we determined the seroprevalence to rickettsioses within rural and urban populations of northern Vietnam. Prevalence of individuals with evidence of prior rickettsial infections (IgG positive) was surprisingly low, with 9.14% (83/908) testing positive to the three major rickettsial serogroups thought to circulate in the region. Prevalence of typhus group rickettsiae (TG)–specific antibodies (6.5%, 58/908) was significantly greater than scrub typhus group orientiae (STG)– or spotted fever group rickettsiae (SFG)–specific antibodies (P < 0.05). The majority of TG seropositives were observed among urban rather than rural residents (P < 0.05). In contrast, overall antibody prevalence to STG and SFG were both very low (1.1%, 10/908 for STG; 1.7%, 15/908 for SFG), with no significant differences between rural and urban residents. These results provide data on baseline population characteristics that may help inform development of Rickettsia serological testing criteria in future clinical studies. PMID:28500808
Kim, Choon-Mee; Cho, Min Keun; Yun, Na-Ra; Kim, Seok Won; Jang, Sook Jin; Ahn, Young-Joon; Lim, Donghoon
2015-01-01
We retrospectively evaluated the accuracy of conventional PCR targeting the 16S rRNA gene (16S C-PCR) using the Ot-16sRF1/Ot-16sRR1 primers for diagnosing scrub typhus. The diagnosis of Orientia tsutsugamushi infection by 16S C-PCR presented an increased sensitivity of 87.0% and specificity of 100% compared with those obtained with other targets and is thus a simple and clinically useful method with good diagnostic accuracy. PMID:26491185
Revisiting doxycycline in pregnancy and early childhood – time to rebuild its reputation?
Cross, Ruby; Ling, Clare; Day, Nicholas P. J.; McGready, Rose; Paris, Daniel H.
2016-01-01
ABSTRACT Introduction: Doxycycline is highly effective, inexpensive with a broad therapeutic spectrum and exceptional bioavailability. However these benefits have been overshadowed by its classification alongside the tetracyclines – class D drugs, contraindicated in pregnancy and in children under 8 years of age. Doxycycline-treatable diseases are emerging as leading causes of undifferentiated febrile illness in Southeast Asia. For example scrub typhus and murine typhus have an unusually severe impact on pregnancy outcomes, and current mortality rates for scrub typhus reach 12-13% in India and Thailand. The emerging evidence for these important doxycycline-treatable diseases prompted us to revisit doxycycline usage in pregnancy and childhood. Areas Covered: A systematic review of the available literature on doxycycline use in pregnant women and children revealed a safety profile of doxycycline that differed significantly from that of tetracycline; no correlation between the use of doxycycline and teratogenic effects during pregnancy or dental staining in children was found. Expert Opinion: The change of the US FDA pregnancy classification scheme to an evidence-based approach will enable adequate evaluation of doxycycline in common tropical illnesses and in vulnerable populations in clinical treatment trials, dosage-optimization pharmacokinetic studies and for the empirical treatment of undifferentiated febrile illnesses, especially in pregnant women and children. PMID:26680308
Tay, Sun Tee; Mohamed Zan, Hafizatul Anis; Lim, Yvonne A L; Ngui, Romano
2013-01-01
Limited data is available on the current status of scrub typhus infection in the aboriginal population in Malaysia. This study was aimed to provide recent data on the degree of exposure of 280 individuals from seven aboriginal subgroups to Orientia tsutsugamushi (causative agent of scrub typhus) in West Malaysia. The environment, socioeconomic and behavioural risk factors associated with the disease were also investigated. The antibody prevalence to O. tsutsugamushi ranged from 0 to 36.4% in seven subgroups, with high prevalence rates noted in subgroups involved in agricultural activity and the lowest prevalence rates noted in subgroups whose main occupations were associated to fishing. Univariate analysis indicated populations with age above 18 years (OR = 1.15, 95% CI = 1.02-1.30, P = 0.015), working (OR = 1.99, 95% CI = 1.01-3.92, P = 0.044), working at agriculture area (OR = 1.18, 95% CI = 0.98-1.42, P = 0.031), receiving household income less than US$ 166.7 (RM500) per month (OR = 2.43, 95% CI = 1.16-5.11, P = 0.016) and having close contact with animal pets (OR = 4.06, 95% CI = 1.20-13.76, P = 0.016) are significantly associated with exposure to O. tsutsugamushi. Multivariate analysis confirms that participants who are above 18 years old, receiving household income less than US$ 166.7 (RM500) per month and having close contact with animal pets are 3.6 times (95% CI = 1.81-7.03, P<0.001), 1.3 times (95% CI = 1.14-1.64, P = 0.002) and 1.2 times (95% CI = 1.05-1.06, P = 0.006) more likely to have exposure to O. tsutsugamushi, respectively. The present study indicates that scrub typhus is still an important disease in the aboriginal population in Malaysia. Awareness about the disease and education on the preventive measures are important in reducing the risk of acquiring scrub typhus in the population studied.
Blacksell, Stuart D.; Tanganuchitcharnchai, Ampai; Jintaworn, Suthatip; Kantipong, Pacharee; Richards, Allen L.; Day, Nicholas P. J.
2016-01-01
The enzyme-linked immunosorbent assay (ELISA) has been proposed as an alternative serologic diagnostic test to the indirect immunofluorescence assay (IFA) for scrub typhus. Here, we systematically determine the optimal sample dilution and cutoff optical density (OD) and estimate the accuracy of IgM ELISA using Bayesian latent class models (LCMs). Data from 135 patients with undifferentiated fever were reevaluated using Bayesian LCMs. Every patient was evaluated for the presence of an eschar and tested with a blood culture for Orientia tsutsugamushi, three different PCR assays, and an IgM IFA. The IgM ELISA was performed for every sample at sample dilutions from 1:100 to 1:102,400 using crude whole-cell antigens of the Karp, Kato, and Gilliam strains of O. tsutsugamushi developed by the Naval Medical Research Center. We used Bayesian LCMs to generate unbiased receiver operating characteristic curves and found that the sample dilution of 1:400 was optimal for the IgM ELISA. With the optimal cutoff OD of 1.474 at a sample dilution of 1:400, the IgM ELISA had a sensitivity of 85.7% (95% credible interval [CrI], 77.4% to 86.7%) and a specificity of 98.1% (95% CrI, 97.2% to 100%) using paired samples. For the ELISA, the OD could be determined objectively and quickly, in contrast to the reading of IFA slides, which was both subjective and labor-intensive. The IgM ELISA for scrub typhus has high diagnostic accuracy and is less subjective than the IgM IFA. We suggest that the IgM ELISA may be used as an alternative reference test to the IgM IFA for the serological diagnosis of scrub typhus. PMID:27008880
1977-09-01
admitted and that scrub typh us remains the most comon cause of fever . A single oral dose of 200 mg of doxy cycline was shown to be as effective as a...the S rural population of Malaysia. Tetracycline eliminates fever and S other symptoms more rapidly than chioramphenicol, and relapses are not...since an eschar and rash are not seen in the majority of Malaysian cases, and common clinical features of scrub typhus , such as fever , headache and
Ding, Lei; Li, Zhong; Wang, Xian-jun; Ding, Shu-jun; Zhang, Meng; Zhao, Zhong-tang
2012-04-01
To explore the epidemic features of scrub typhus between year 2006 and 2010 in Shandong Province. Based on the data collected through Diseases Reporting Information System between year 2006 and 2010 in Shandong province, 1291 cases of scrub typhus were selected. The study described the population distribution features of the scrub typhus patients, and explored the temporal and spatial distribution features of the disease by applying the methods of spatial thematic mapping, inverse distance weighted, spatial autocorrelation analysis, spatial clustering analysis, temporal clustering analysis and spatial variation analysis in temporal trends based on Geographic Information software (ArcGIS 9.3) and Spatial Clustering Software (SatScan 7.0). The onset age of the 1291 patients ranged between 1 and 92 years old.639 out of 1291 patients were over 55 years old, accounting for 49.5%.640 patients were male and the other 651 patients were female, occupying 49.6% and 50.4% respectively. The gender ratio was 1:1.02. Patients were found in farmers, workers, students and preschool children. However, most of the cases were farmers, up to 84.8% (1095/1291). Global Moran's I index was 0.324 (P < 0.01). The local Moran's I index in 8 locations were proved to have statistical significance (P < 0.01); all of which were H-H clustering areas. Gangcheng (38 cases), Laicheng (154 cases), Xintai (160 cases) and Donggang (105 cases) were important locations, whose local Moran's I index were 2.111, 1.642, 1.277 and 0.775 respectively. The clustering period of scrub typhus in respective year were as follows: 2006.09.23 - 2006.11.20 (202 cases), 2007.10.02 - 2007.11.11 (197 cases), 2008.09.30 - 2008.11.07 (302 cases), 2009.09.25 - 2009.11.10 (204 cases), and 2010.10.05 - 2010.11.13 (226 cases), whose RR values were separately 45.55, 34.60, 50.64, 53.09 and 79.84 (P < 0.01). Two spatial clustering area were found in the study, one was the area centered Taian and Xintai with radiation radius at 58.28 km (542 cases) and the other one was the area centered Rizhao and Donggang with radiation radius at 22.68 km (134 cases), whose RR values were 4.52 and 3.96 (P < 0.01). The spatial features of the two clustering areas were inland low hills area and coastal hills area. The highest annual growth rate of the disease was 45.04%, found in the area centered Linyi and Mengyin counties, with the radiation radius at 45.82 km. The RR value was 3.68 (P < 0.01). The majority of the scrub typhus patients were middle-aged and elderly farmers. The epidemic peak was between the last 10 days of September and the first 10 days of November. A positive spatial correlation of the disease was found; and most cases clustered in inland low hills area and costal hills area; especially the area around Linyi and Mengyin, with the highest annual growth rates of the disease.
Sumonwiriya, Manutsanun; Paris, Daniel H; Sunyakumthorn, Piyanate; Anantatat, Tippawan; Jenjaroen, Kemajittra; Chumseng, Suchintana; Im-Erbsin, Rawiwan; Tanganuchitcharnchai, Ampai; Jintaworn, Suthatip; Blacksell, Stuart D; Chowdhury, Fazle R; Kronsteiner, Barbara; Teparrukkul, Prapit; Burke, Robin L; Lombardini, Eric D; Richards, Allen L; Mason, Carl J; Jones, James W; Day, Nicholas P J; Dunachie, Susanna J
2017-09-01
Scrub typhus is a febrile infection caused by the obligate intracellular bacterium Orientia tsutsugamushi, which causes significant morbidity and mortality across the Asia-Pacific region. The control of this vector-borne disease is challenging due to humans being dead-end hosts, vertical maintenance of the pathogen in the vector itself, and a potentially large rodent reservoir of unclear significance, coupled with a lack of accurate diagnostic tests. Development of an effective vaccine is highly desirable. This however requires better characterization of the natural immune response of this neglected but important disease. Here we implement a novel IFN-γ ELISpot assay as a tool for studying O. tsutsugamushi induced cellular immune responses in an experimental scrub typhus rhesus macaque model and human populations. Whole cell antigen for O. tsutsugamushi (OT-WCA) was prepared by heat inactivation of Karp-strain bacteria. Rhesus macaques were infected intradermally with O. tsutsugamushi. Freshly isolated peripheral blood mononuclear cells (PBMC) from infected (n = 10) and uninfected animals (n = 5) were stimulated with OT-WCA, and IFN-γ secreting cells quantitated by ELISpot assay at five time points over 28 days. PBMC were then assayed from people in a scrub typhus-endemic region of Thailand (n = 105) and responses compared to those from a partially exposed population in a non-endemic region (n = 14), and to a naïve population in UK (n = 12). Mean results at Day 0 prior to O. tsutsugamushi infection were 12 (95% CI 0-25) and 15 (2-27) spot-forming cells (SFC)/106 PBMC for infected and control macaques respectively. Strong O. tsutsugamushi-specific IFN-γ responses were seen post infection, with ELISpot responses 20-fold higher than baseline at Day 7 (mean 235, 95% CI 200-270 SFC/106 PBMC), 105-fold higher at Day 14 (mean 1261, 95% CI 1,097-1,425 SFC/106 PBMC), 125-fold higher at Day 21 (mean 1,498, 95% CI 1,496-1,500 SFC/106 PBMC) and 118-fold higher at Day 28 (mean 1,416, 95% CI 1,306-1,527 SFC/106 PBMC). No significant change was found in the control group at any time point compared to baseline. Humans from a scrub typhus endemic region of Thailand had mean responses of 189 (95% CI 88-290) SFC/106 PBMC compared to mean responses of 40 (95% CI 9-71) SFC/106 PBMC in people from a non-endemic region and 3 (95% CI 0-7) SFC/106 PBMC in naïve controls. In summary, this highly sensitive assay will enable field immunogenicity studies and further characterization of the host response to O. tsutsugamushi, and provides a link between human and animal models to accelerate vaccine development.
Studies on Typhus and Spotted Fever.
1986-09-01
Rocky Mountain spotted fever , scrub typhus, trench fever, R. prowazekil, R. mooseri, R. Canada, R...rickettsia- static action: erythromycin and rifampin. Although erythromycin aiready had proven to be unreliable in the treatment of Rocky Mountain spotted fever , the...DC. 9. DuPont, H. L., R. B. Hornick, A. T. Dawkins, G. G. heiner. I. B. Fabrikant, C. L. Wisseman. Jr, and T. E. Woodward. 1VU1. Rocky Mountain spotted fever :
2006-06-01
fever, relapsing fever, scrub typhus , and visceral leishmaniasis were either principal or contributing factors affecting overall mortal- ity and...human health. In 26 of 52 retro- spectively analyzed wars from 480 BC to 2002 AD, vector-borne diseases like plague, louse-borne typhus , malaria, yellow
Qi, Yong; Yin, Qiong; Shao, Yinxiu; Cao, Min; Li, Suqin; Chen, Hongxia; Shen, Wanpeng; Rao, Jixian; Li, Jiameng; Li, Xiaoling; Sun, Yu; Lin, Yu; Deng, Yi; Zeng, Wenwen; Zheng, Shulong; Liu, Suyun; Li, Yuexi
2018-05-01
Orientia tsutsugamushi is an obligate intracellular pathogen that causes scrub typhus. Diagnosing scrub typhus remains a challenge, and a sensitive, specific, simple, and rapid diagnostic test is still needed. A recombinase polymerase amplification (RPA) assay combined with a lateral flow (LF) test targeting the 56-kDa gene of a Karp-like strain of O. tsutsugamushi was developed and optimized. The detection limits, sensitivity, specificity, and simulative clinical performance were evaluated. Primers and probe were screened to establish the RPA assay, and the reaction conditions were optimized. The detection limit was 10 copies/reaction in detecting plasmid DNA and 12 copies/reaction in detecting genomic DNA. The RPA-LF method could differentiate O. tsutsugamushi from other phylogenetically related bacteria. The sensitivity was 100% and specificity was over 90%, when evaluated using infected animal samples or simulative clinical samples. Furthermore, the method was completed in 20min at 37°C followed by a 3-5min incubation at room temperature for the development of an immunochromatographic strip, and the results could be determined visually. This method is promising for wide-ranging use in basic medical units considering that it requires minimal instruments and infrastructure and is highly time-efficient, sensitive, and specific for diagnosing scrub typhus. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Endoscopic Characteristics Comparison of Helicobacter pylori and Orientia tsutsugamushi Infection
Kim, Dong-Min; Yun, Na Ra; Sul, Hyoung; Kim, Choon-Mee
2017-01-01
Abstract Background Aside from Helicobacter pylori, another cause for the development or worsening of gastrointestinal ulcers is scrub typhus, an acute febrile disease caused by Orientia tsutsugamushi. We aimed to compare the endoscopic characteristics of peptic ulcers caused by these infectious agents. Methods This retrospective case–control study involved patients who underwent upper gastrointestinal endoscopy at Chosun University Hospital in Korea. Results In total, 141 patients with peptic ulcer were included in the study. Compared with patients with O. tsutsugamushi infection (n = 62; age, 63.8 ± 12.1 years; male sex, 42%), those with H. pylori infection (n = 79; age, 53.0 ± 14.8 years; male sex, 81%) were younger and more likely to be male (P < 0.001 for both). Patients with O. tsutsugamushi infection were more likely to have multiple lesions (40/62, 64.5% vs. 37/79, 46.8%; P = 0.042) and irregular-shaped lesions (27/62, 43.6% vs. 20/79, 25.3%; P = 0.031). Patients with H. pylori infection had higher incidence of hemorrhagic ulcers (26/79, 32.9% vs. 8/62, 12.9%; P = 0.007), and lesions occurred most often in the duodenum (43.0%), followed by the antrum (36.7%), body (34.2%), and angle (12.7%) of the stomach. In patients with O. tsutsugamushi infection, lesions occurred most often in the antrum (70.97%) of the stomach. In both groups, gastric ulcer lesions occurred most often in the antrum, followed by the body and angle of the stomach (36.7% vs. 70.97%, 34.2% vs. 22.6%, and 12.7% vs. 14.5% for gastric ulcers associated with H. pylori and O. tsutsugamushi infection, respectively). Patients with O. tsutsugamushiinfection had significantly higher incidence of ulcers on the antrum (70.97% vs. 36.7%, P < 0.001) and the greater curvature (45.2% vs. 24.0%, P = 0.012). Finally, 35.5% of patients with gastric ulcer caused by scrub typhus also had duodenal ulcer. Conclusion This is the first study to compare endoscopic features of peptic ulcers caused by H. pylori and O. tsutsugamushi. Peptic ulcers in patients with H. pylori infection occurred predominantly in the antrum/body/lesser curvature and presented with single, round/oval lesions, while ulcers in patients with scrub typhus occurred predominantly in the antrum/greater curvature and presented with multiple, irregular lesions. Scrub typhus should be considered as a cause of duodenal ulcer in scrub typhus-endemic areas. Disclosures All authors: No reported disclosures.
Tay, Sun Tee; Mohamed Zan, Hafizatul Anis; Lim, Yvonne A. L.; Ngui, Romano
2013-01-01
Background Limited data is available on the current status of scrub typhus infection in the aboriginal population in Malaysia. This study was aimed to provide recent data on the degree of exposure of 280 individuals from seven aboriginal subgroups to Orientia tsutsugamushi (causative agent of scrub typhus) in West Malaysia. The environment, socioeconomic and behavioural risk factors associated with the disease were also investigated. Methods/Findings The antibody prevalence to O. tsutsugamushi ranged from 0 to 36.4% in seven subgroups, with high prevalence rates noted in subgroups involved in agricultural activity and the lowest prevalence rates noted in subgroups whose main occupations were associated to fishing. Univariate analysis indicated populations with age above 18 years (OR = 1.15, 95% CI = 1.02–1.30, P = 0.015), working (OR = 1.99, 95% CI = 1.01–3.92, P = 0.044), working at agriculture area (OR = 1.18, 95% CI = 0.98–1.42, P = 0.031), receiving household income less than US$ 166.7 (RM500) per month (OR = 2.43, 95% CI = 1.16–5.11, P = 0.016) and having close contact with animal pets (OR = 4.06, 95% CI = 1.20–13.76, P = 0.016) are significantly associated with exposure to O. tsutsugamushi. Multivariate analysis confirms that participants who are above 18 years old, receiving household income less than US$ 166.7 (RM500) per month and having close contact with animal pets are 3.6 times (95% CI = 1.81–7.03, P<0.001), 1.3 times (95% CI = 1.14–1.64, P = 0.002) and 1.2 times (95% CI = 1.05–1.06, P = 0.006) more likely to have exposure to O. tsutsugamushi, respectively. Conclusion The present study indicates that scrub typhus is still an important disease in the aboriginal population in Malaysia. Awareness about the disease and education on the preventive measures are important in reducing the risk of acquiring scrub typhus in the population studied. PMID:23936576
Kim, Si Heon; Jang, Jae Yeon
2010-09-01
Infectious diseases are known to be affected by climate change. We investigated if the infectious diseases were related to meteorological factors in Korea. Scrub typhus, hemorrhagic fever with renal syndrome (HFRS), leptospirosis, malaria and Vibrio vulnificus sepsis among the National Notifiable Infectious Diseases were selected as the climate change-related infectious diseases. Temperature, relative humidity and precipitation were used as meteorological factors. The study period was from 2001 through 2008. We examined the seasonality of the diseases and those correlations with meteorological factors. We also analyzed the correlations between the incidences of the diseases during the outbreak periods and monthly meteorological factors in the hyper-endemic regions. All of the investigated diseases showed strong seasonality; malaria and V. vulnificus sepsis were prevalent in summer and scrub typhus, HFRS and leptospirosis were prevalent in the autumn. There were significant correlations between the monthly numbers of cases and all the meteorological factors for malaria and V. vulnificus sepsis, but there were no correlation for the other diseases. However, the incidence of scrub typhus in hyper-endemic region during the outbreak period was positively correlated with temperature and humidity during the summer. The incidences of HFRS and leptospirosis had positive correlations with precipitation in November and temperature and humidity in February, respectively. V. vulnificus sepsis showed positive correlations with precipitation in April/May/July. In Korea, the incidences of the infectious diseases were correlated with meteorological factors, and this implies that the incidences could be influenced by climate change.
Kuo, Chi-Chien; Huang, Jing-Lun; Shu, Pei-Yun; Lee, Pei-Lung; Kelt, Douglas A; Wang, Hsi-Chieh
2012-09-01
The increase in global travel and trade has facilitated the dissemination of disease vectors. Globalization can also indirectly affect vector-borne diseases through the liberalization of cross-border trade, which has far-reaching, worldwide effects on agricultural practices and may in turn influence vectors through the modification of the ecological landscape. While the cascading effect of economic globalization on vector-borne diseases, sometimes acting synergistically with regional agricultural policy, could be substantial and have significant economic, agricultural, and public health implications, research into this remains very limited. We evaluated how abandonment of rice paddies in Taiwan after joining the World Trade Organization, along with periodic plowing, an agricultural policy to reduce farm pests in abandoned fields can unexpectedly influence risks to diseases transmitted by ticks and chiggers (larval trombiculid mites), which we collected from their small-mammal hosts. Sampling was limited to abandoned (fallow) and plowed fields due to the challenge of trapping small mammals in flooded rice paddies. Striped field mice (Apodemus agrarius) are the main hosts for both vectors. They harbored six times more ticks and three times more chiggers in fallow than in plowed plots. The proportion of ticks infected with Rickettsia spp. (etiologic agent of spotted fever) was three times higher in fallow plots, while that of Orientia tsutsugamushi (scrub typhus) in chiggers was similar in both treatments. Fallow plots had more ground cover and higher vegetation than plowed ones. Moreover, ticks and chiggers in both field types were dominated by species known to infest humans. Because ticks and chiggers should exhibit very low survival in flooded rice paddies, we propose that farm abandonment in Taiwan, driven by globalization, may have inadvertently led to increased risks of spotted fever and scrub typhus. However, periodic plowing can unintentionally mitigate vector burdens. Economic globalization can have unexpected consequences on disease risk through modification of the agricultural landscape, but the outcome may also be influenced by agricultural policies, calling for further research on vector-borne diseases and their control from broader perspectives.
Spicer, P E; Taufa, T; Benjamin, A L
2007-01-01
A medical investigation was carried out in April 2001 into an outbreak of a mysterious haemorrhagic disease and deaths in the remote picturesque Strickland River area of Papua New Guinea (PNG). The area is in part of the Southern Highlands and West Sepik Provinces and situated downstream from the Porgera Joint Venture gold mine. 9 villages were visited and 140 persons, consisting of immediate blood relatives of the deceased (cases) and others in the village picked at random (controls), were physically examined. Specimens of blood, urine and faeces were collected from each person for laboratory tests in PNG and Australia. Positive sera for dengue (15%) and Japanese encephalitis (JE) (6%) were identified. Surprisingly, a number of the sera were positive for scrub typhus (Orientia tsutsugamushi) (28%) and spotted fever (Rickettsia australis) (11%). The last reported cases of scrub typhus in PNG were during World War Two among the allied troops. This is the first time spotted fever (R. australis) has been reported in PNG. These conditions may have been the cause of the deaths described by the villagers. However, there were significantly more dengue-positive results among relatives of the deceased than non-relatives though no such difference was found with rickettsial infections: haemorrhagic dengue fever is thus the most likely cause of this recurring outbreak. Mining did not appear to be a direct causal factor for the deaths in the area.
Mite vectors (Acari: Trombiculidae) of scrub typhus in a new endemic area in northern Kyoto, Japan.
Takahashi, Mamoru; Misumi, Hitoko; Urakami, Hiroshi; Nakajima, Satoko; Furui, Sataro; Yamamoto, Seigo; Furuya, Yumiko; Misumi, Motohiro; Matsumoto, Isao
2004-01-01
Between 1983 and 1999, 27 human cases of scrub typhus (two fatal) occurred in the Nodagawa River basin of northern Kyoto, Japan, an area where no cases had been previously reported. Antibody screening of infected patients' sera showed that nine of 15 patients had high titers against the Gilliam type of Orientia tsutsugamushi (Hayashi). To determine the vector mite transmitting the disease, we studied rodent and chigger populations in and near a rice field alongside the Nodagawa River between 1996 and 1999. The most common rodent species was Microtus montebelli (Milne-Edwards), representing 73.3% (33/45) of the population. The mite index (average number of mites per infested host) was highest (190.8) in Leptotrombidium pallidum Nagayo, Mitamura & Tamiya parasitizing on M. montebelli, followed by Leptotrombidium intermedium (Nagayo, Mitamura & Tamiya) (174.9) on the same host species. Orientia tsutsugamushi was isolated from 60.5% (23/38) of rodents and from 71.2% (37/52) of pools of engorged L. pallidum. The Gilliam type of O. tsutsugamushi was most prevalent in rodents, and in engorged L. pallidum and it was the only type recovered from 10 isolates inoculated into L 929 cells for indirect immunofluorescence examination. Orientia tsutsugamushi infected 14.3% (181/1263) and 14.8% (306/2066) of engorged and unfed L. pallidum larvae, respectively, and was also detected in 0.055% (2/3634) of unfed L. intermedium, although previous studies suggest that this mite rarely bites humans. These results show that L. pallidum is the primary vector species of scrub typhus in this new endemic area in Japan.
Ogawa, Motohiko; Satoh, Masaaki; Saijo, Masayuki; Ando, Shuji
2017-01-05
Scrub typhus is a mite-borne rickettsiosis caused by infection of Orientia tsutsugamushi, which is endemic to several Asia-Pacific Rim countries, including Japan. Although micro-indirect immunofluorescent assay (micro-IFA) is the standard method for the serological diagnosis of scrub typhus, enzyme-linked immunosorbent assay (ELISA) is considered to be more objective, by providing digitized results as opposed to being subject to the judgment of the evaluator as in micro-IFA. Therefore, the aim of this study was to develop a broad-ranging ELISA using the five major prevalent serotypes of O. tsutsugamushi in Japan as the antigens. Furthermore, in contrast to previous studies that used purified microorganisms via ultracentrifugation, we directly used the infected cells, and evaluated the diagnostic accuracy of this simplified method to that of micro-IFA. Evaluation of paired patient sera against the five serotypes showed that the accuracy of ELISA relative to micro-IFA was 87.4 and 79.5% for immunoglobulin (Ig)M and IgG assays, respectively, at the optimized cut-off value. Further evaluation of patient sera against the expected serotype of the infecting strain showed that the accuracy of ELISA compared to micro-IFA increased to 100 and 97.4% in the IgM and IgG assays, respectively. This suggests that use of the five prevalent serotypes contributed to the increase of the accuracy of ELISA. When applying the criteria of serological diagnosis for paired sera samples to ELISA, all 19 patients were diagnosed as positive; a ≥4-fold elevation of the antibody titer was observed in 15 of 19 patients that were positive, and very high antibody titers were observed in both paired sera samples of the remaining four patients. In addition, all samples of healthy subjects and patients with other types of rickettsiosis were diagnosed as negative using these criteria. Our results suggest the excellent performance of the new broad-ranging and convenient ELISA, which appears to be applicable for the diagnosis of scrub typhus patients infected with the wide variety of prevalent strains in Japan. Furthermore, the ELISA is more objective than the micro-IFA, and can therefore provide more accurate diagnoses in Japan.
2010-02-01
archived samples, we assessed the diagnostic capacity of a rapid immunochromatographic test (ICT) for the detection of Orientia tsutsugamushi IgM and...illness in the Asia-Pacific region. As very few health facilities have accessible accurate diagnostic tests , the diagnosis of scrub fever must be based...develop- ment of rapid , diagnostic tests by the use of immunochromato- graphic test (ICf) technologies has provided a mechanism for point-of-care
Scrub Typhus in a Tertiary Care Hospital in North India.
Sharma, Navneet; Biswal, Manisha; Kumar, Abhay; Zaman, Kamran; Jain, Sanjay; Bhalla, Ashish
2016-08-03
Scrub typhus, a zoonotic disease caused by the bacterium Orientia tsutsugamushi, has become endemic in many parts of India. We studied the clinical profile of this infection in 228 patients that reported to this tertiary care center from July 2013 to December 2014. The median age of patients was 35 years (interquartile range = 24.5-48.5 years), and 111 were males and 117 females. A high-grade fever occurred in 85%, breathlessness in 42%, jaundice in 32%, abdominal pain in 28%, renal failure in 11%, diarrhea in 10%, rashes in 9%, and seizures in 7%. Common laboratory abnormalities at presentation were a deranged hepatic function in 61%, anemia in 54%, leukopenia in 15%, and thrombocytopenia in 90% of our patients. Acute kidney injury (32%), acute respiratory distress syndrome (ARDS) (25%), and disseminated intravascular coagulation (DIC) (16%) were the commonest complications. A hepatorenal syndrome was seen in 38% and multiple organ dysfunction syndrome (MODS) in 20% patients. The overall case fatality rate was 13.6%. In univariate analysis, ARDS requiring mechanical ventilation, acute kidney injury requiring hemodialysis, hypotension requiring inotropic support, central nervous system dysfunction at presentation, and MODS were inversely associated with survival. Survival was significantly higher in patients that presented with a duration of fever < 10 days compared with those that presented ≥ 12 days (P < 0.05) after onset. In conclusion, scrub typhus has become a leading infectious disease in north India and an important cause of infectious fever. An increasing awareness of this disease coupled with prompt management will go a long way in reducing both morbidity and mortality from this disease. © The American Society of Tropical Medicine and Hygiene.
Aetiology of acute encephalitis syndrome in Uttar Pradesh, India from 2014 to 2016.
Jain, Parul; Prakash, Shantanu; Khan, Danish N; Garg, Ravindra Kumar; Kumar, Rashmi; Bhagat, Amit; Ramakrishna, V; Jain, Amita
2017-01-01
It is imperative to know the aetiology of acute encephalitis syndrome (AES) for patient management and policy making. The present study was carried out to determine the prevalence of common aetiological agents of AES in Uttar Pradesh (UP) state of India. Serum and/or CSF samples were collected from AES patients admitted at Gandhi Memorial and Associated Hospital, King George's Medical University, Lucknow, a tertiary care centre, UP during 2014-16. Cerebrospinal fluid (CSF) and serum samples from cases were tested for IgM antibodies against Japanese encephalitis virus (anti-JEV), and dengue virus (anti-DENV) by ELISA; and for enterovirus, herpes simplex virus (HSV) and varicella zoster virus (VZV) by real-time PCR. Serum samples of cases having sufficient CSF volume, were also tested for anti-scrub typhus IgM antibodies and for Neisseria meningitides, Streptococcus pneumoniae and Haemophilus influenzae. JEV and DENV (8% each) were the most common identified aetiology from the 4092 enrolled patients. Enterovirus, HSV and VZV, each were detected in <1% AES cases. Co-positivity occurred in 48 cases. Scrub typhus (31.8%) was the most common aetiology detected. Haemophilus influenzae and S. pneumoniae were detected in 0.97 and 0.94% cases, respectively, however, N. meningitides was not detected in any of the cases. About 40% of the JEV/DENV positive AES cases were adults. The gap between the total number of AES cases and those with JEV/ DENV infection increased during monsoon and post-monsoon seasons. Scrub typhus, JEV and DENV are the main aetiological agents of AES in UP. DENV and JEV can no longer be considered paediatric diseases. The prevalence of non-JEV/DENV aetiology of AES increases in the monsoon and post-monsoon seasons.
A RICKETTSIAL INFECTION IN CANADIAN VOLES
Baker, James A.
1946-01-01
From apparently normal voles captured on Grosse Isle, Province of Quebec, Canada, an infective agent has been grown in embryonated eggs, and by inoculation an inapparent infection was established in voles, mice, guinea pigs, hamsters, and rats. No growth of the agent was obtained in the absence of living cells, and the manner of its development in the yolk sac of embryonated eggs, as well as morphological, epidemiological, and pathogenic features, indicates a rickettsial nature. The inability to transmit infection by either cage or intrauterine contact points to a vector, and mites are shown to have a probable part in the epidemiology. Mice infected with the vole agent resist lethal doses of the Karp strain of scrub typhus, and certain epidemiological, morphological, and immunological features support the relationship indicated by the mouse tests. It is therefore concluded that voles on this island have an inapparent infection due to a rickettsia that may be related to the rickettsia of scrub typhus. PMID:19871552
Chao, Chien-Chung; Huber, Erin S; Porter, Terrisita B; Zhang, Zhiwen; Ching, Wei-Mei
2011-06-01
Orientia tsutsugamushi, the etiologic agent of scrub typhus, has a highly expressed and immunodominant 56-kD outer membrane protein. This protein is one of the leading candidates for diagnosis and vaccine development for scrub typhus. Previous studies using recombinant 56-kD protein (r56s) derived from Karp strain (Kpr56) in a mouse model have shown good homologous protection but only moderate to poor heterologous protection. We evaluated the cross-reactivity of recombinant 56-kD proteins from Karp, Kato, Gilliam, TA763, and three chimeric 56-kD proteins. Not all r56s are equally reactive with strain-specific serum samples. These data provide a first glance of how reactive these r56s are toward the antiserum of different strains and which r56 exhibits the broadest reactivity. A formulation of this combination has the potential to provide broad protection against the heterologous challenge and to be used in a highly sensitive diagnostic assay.
Seroepidemiololgy of rickettsioses in Sri Lanka: a patient based study
2011-01-01
Background Rickettsioses are emerging infections in Sri Lanka as shown by the increase in the number of clinically diagnosed rickettsial patients being reported to the Epidemiology Unit, Sri Lanka. However, mapping the disease for the whole island with laboratory confirmed cases has not been previously carried out. Methods 615 samples received from 23 hospital representing 8 provinces were tested using ELISA or IFA methods and clinical data was collected using a validated questionnaire. Results Rash was found among more spotted fever seropositive patients than scrub typhus seropositive patients while the opposite was true for the presence of eschar. Spotted fever and scrub typhus was found in a geographically restricted manner. Consistent temporal patterns were seen for the presentation of patients with rickettsioses in Kandy and Kurunegala districts for 2009 and 2010. Conclusions This study expanded knowledge on the distribution of rickettsioses in Sri Lanka and their clinical profiles which in turn helps in the clinical diagnosis of these infections. PMID:22118601
Janardhanan, Jeshina; Prakash, John Antony Jude; Abraham, Ooriapadickal C; Varghese, George M
2014-05-01
A nested polymerase chain reaction (PCR) targeting the 56-kDa antigen gene is currently the most commonly used molecular technique for confirmation of scrub typhus and genotyping of Orientia tsutsugamushi. In this study, we have compared the commonly used nested PCR (N-PCR) with a single-step conventional PCR (C-PCR) for amplification and genotyping. Eschar samples collected from 24 patients with scrub typhus confirmed by IgM enzyme-linked immunosorbent assay were used for DNA extraction following which amplifications were carried out using nested and C-PCR methods. The amplicons were sequenced and compared to other sequences in the database using BLAST. Conventional PCR showed a high positivity rate of 95.8% compared to the 75% observed using N-PCR. On sequence analysis, the N-PCR amplified region showed more variation among strains than the C-PCR amplified region. The C-PCR, which is more economical, provided faster and better results compared to N-PCR. Copyright © 2014 Elsevier Inc. All rights reserved.
2010-01-01
Province, Republic of Korea, 2001-2005 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR (S) 5d. PROJECT NUMBER 5e. TASK...rodent-borne disease surveillance, including rodent bionom- ics, ecology, and hantaviruses , conducted at other U.S. and Korean operated military...2005 as described by O’Guinn et al (2008), as a result of a hantavirus case reported in October 2000 in a U.S. soldier who trained at these sites
Desert Operations Tactics, Techniques, and Procedures. Southwest Asia Focus
1990-11-01
6-5 CONTAM IN ATION TRAN SFER ...................................................................... 6-7 PRINCIPLES OF CONTAMINATION AVOIDANCE...6-14 Decontam ination Principles ....................................................................... 6-14 Aircraft Spraydown...moisture or food, lice, mites, and flies can be extremely unpleasant and carry diseases such as scrub typhus and dysentery. The stings of many
Endemic Scrub Typhus–like Illness, Chile
Balcells, M. Elvira; Rabagliati, Ricardo; García, Patricia; Poggi, Helena; Oddó, David; Concha, Marcela; Abarca, Katia; Jiang, Ju; Richards, Allen L.; Fuerst, Paul A.
2011-01-01
We report a case of scrub typhus in a 54-year-old man who was bitten by several terrestrial leeches during a trip to Chiloé Island in southern Chile in 2006. A molecular sample, identified as related to Orientia tsutsugamushi based on the sequence of the16S rRNA gene, was obtained from a biopsy specimen of the eschar on the patient’s leg. Serologic analysis showed immunoglobulin G conversion against O. tsutsugamushi whole cell antigen. This case and its associated molecular analyses suggest that an Orientia-like agent is present in the Western Hemisphere that can produce scrub typhus–like illness. The molecular analysis suggests that the infectious agent is closely related, although not identical, to members of the Orientia sp. from Asia. PMID:21888791
Harris, Patrick N A; Oltvolgyi, Csongor; Islam, Aminul; Hussain-Yusuf, Hazizul; Loewenthal, Mark R; Vincent, Gemma; Stenos, John; Graves, Stephen
2016-06-01
Scrub typhus is caused by the obligate intracellular bacterium Orientia tsutsugamushi and is endemic to many countries in the Asia-Pacific region, including tropical Australia. We describe a recent large outbreak amongst military personnel in north Queensland. A total of 45 clinical cases were identified (36% of all potentially exposed individuals). This occurred despite existing military protocols stipulating the provision of doxycycline prophylaxis. Doxycycline resistance in O. tsutsugamushi has been described in South-East Asia, but not Australia. In one case, O. tsutsugamushi was cultured from eschar tissue and blood. Using quantitative real-time PCR to determine susceptibility to doxycycline for the outbreak strain, a minimum inhibitory concentration (MIC) of ≤0.04 μg/mL was found, indicating susceptibility to this agent. It seems most probable that failure to adhere to adequate prophylaxis over the duration of the military exercise accounted for the large number of cases encountered rather than doxycycline resistance. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.
New Genotypes of Orientia tsutsugamushi Isolated from Humans in Eastern Taiwan
Lin, Chin-Hui; Chen, Tren-Yi; Chen, Li-Kuang
2012-01-01
Scrub typhus, an acute febrile illness, is caused by the obligate intracellular bacterium Orientia tsutsugamushi. In our study, O. tsutsugamushi was rapidly detected and typed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis of the 56-kDa type-specific antigen (TSA) gene. To investigate the genotypes of clinical variants of O. tsutsugamushi, we collected 3223 blood samples from eastern Taiwanese patients with suspected scrub typhus from 2002 to 2008. In total, 505 samples were found to be positive for scrub typhus infection by PCR, and bacteria were isolated from 282 of them. Four prototype genotype strains (Karp, Kato, Kawasaki and Gilliam) and eleven different Taiwanese genotype isolates (Taiwan-A, -B, -C, -D, -E, -G, -H, -J, -N, -O and -P) were identified by RPLF analysis. Taiwan-H, the major genotype in eastern Taiwan, exhibited prevalence and isolation rates of 47.3% (239/505) and 42.6% (120/282), respectively. We also assessed the genetic relatedness of the 56-kDa TSA gene among eight Taiwan-H isolates, thirteen other Taiwanese isolates and 104 DNA sequences deposited in the GenBank database using MEGA version 5.0 and PHYLIP version 3.66. We found that the Taiwan-H isolates formed into a new cluster, which was designated the Taiwan Gilliam-variant (TG-v) cluster to distinguish it from the Japanese Gilliam-variant (JG-v) cluster. According to Simplot analysis, TG-v is a new recombinant strain among Gilliam, Ikeda and Kato. Moreover, the Gilliam-Kawasaki cluster had the highest percentage of RFLP cases and was the most frequently isolated type in eastern Taiwan (50.1%, 253/505; 44.0%, 124/282). These findings shed light on the genetic evolution of O. tsutsugamushi into different strains and may be useful in vaccine development and epidemic disease control in the future. PMID:23071693
Mathematical Modeling for Scrub Typhus and Its Implications for Disease Control.
Min, Kyung Duk; Cho, Sung Il
2018-03-19
The incidence rate of scrub typhus has been increasing in the Republic of Korea. Previous studies have suggested that this trend may have resulted from the effects of climate change on the transmission dynamics among vectors and hosts, but a clear explanation of the process is still lacking. In this study, we applied mathematical models to explore the potential factors that influence the epidemiology of tsutsugamushi disease. We developed mathematical models of ordinary differential equations including human, rodent and mite groups. Two models, including simple and complex models, were developed, and all parameters employed in the models were adopted from previous articles that represent epidemiological situations in the Republic of Korea. The simulation results showed that the force of infection at the equilibrium state under the simple model was 0.236 (per 100,000 person-months), and that in the complex model was 26.796 (per 100,000 person-months). Sensitivity analyses indicated that the most influential parameters were rodent and mite populations and contact rate between them for the simple model, and trans-ovarian transmission for the complex model. In both models, contact rate between humans and mites is more influential than morality rate of rodent and mite group. The results indicate that the effect of controlling either rodents or mites could be limited, and reducing the contact rate between humans and mites is more practical and effective strategy. However, the current level of control would be insufficient relative to the growing mite population. © 2018 The Korean Academy of Medical Sciences.
Lai, Chung-Hsu; Chang, Lin-Li; Lin, Jiun-Nong; Chen, Wei-Fang; Kuo, Li-Li; Lin, Hsi-Hsun; Chen, Yen-Hsu
2013-01-01
Q fever is serologically cross-reactive with other intracellular microorganisms. However, studies of the serological status of Mycoplasma pneumoniae and Chlamydophila pneumoniae during Q fever are rare. We conducted a retrospective serological study of M. pneumoniae and C. pneumoniae by enzyme-linked immunosorbent assay (ELISA), a method widely used in clinical practice, in 102 cases of acute Q fever, 39 cases of scrub typhus, and 14 cases of murine typhus. The seropositive (57.8%, 7.7%, and 0%, p<0.001) and seroconversion rates (50.6%, 8.8%, and 0%, p<0.001) of M. pneumoniae IgM, but not M. pneumoniae IgG and C. pneumoniae IgG/IgM, in acute Q fever were significantly higher than in scrub typhus and murine typhus. Another ELISA kit also revealed a high seropositivity (49.5%) and seroconversion rate (33.3%) of M. pneumoniae IgM in acute Q fever. The temporal and age distributions of patients with positive M. pneumoniae IgM were not typical of M. pneumoniae pneumonia. Comparing acute Q fever patients who were positive for M. pneumoniae IgM (59 cases) with those who were negative (43 cases), the demographic characteristics and underlying diseases were not different. In addition, the clinical manifestations associated with atypical pneumonia, including headache (71.2% vs. 81.4%, p=0.255), sore throat (8.5% vs. 16.3%, p=0.351), cough (35.6% vs. 23.3%, p=0.199), and chest x-ray suggesting pneumonia (19.3% vs. 9.5%, p=0.258), were unchanged between the two groups. Clinicians should be aware of the high seroprevalence of M. pneumoniae IgM in acute Q fever, particularly with ELISA kits, which can lead to misdiagnosis, overestimations of the prevalence of M. pneumoniae pneumonia, and underestimations of the true prevalence of Q fever pneumonia.
Lai, Chung-Hsu; Chang, Lin-Li; Lin, Jiun-Nong; Chen, Wei-Fang; Kuo, Li-Li; Lin, Hsi-Hsun; Chen, Yen-Hsu
2013-01-01
Q fever is serologically cross-reactive with other intracellular microorganisms. However, studies of the serological status of Mycoplasma pneumoniae and Chlamydophila pneumoniae during Q fever are rare. We conducted a retrospective serological study of M. pneumoniae and C. pneumoniae by enzyme-linked immunosorbent assay (ELISA), a method widely used in clinical practice, in 102 cases of acute Q fever, 39 cases of scrub typhus, and 14 cases of murine typhus. The seropositive (57.8%, 7.7%, and 0%, p<0.001) and seroconversion rates (50.6%, 8.8%, and 0%, p<0.001) of M. pneumoniae IgM, but not M. pneumoniae IgG and C. pneumoniae IgG/IgM, in acute Q fever were significantly higher than in scrub typhus and murine typhus. Another ELISA kit also revealed a high seropositivity (49.5%) and seroconversion rate (33.3%) of M. pneumoniae IgM in acute Q fever. The temporal and age distributions of patients with positive M. pneumoniae IgM were not typical of M. pneumoniae pneumonia. Comparing acute Q fever patients who were positive for M. pneumoniae IgM (59 cases) with those who were negative (43 cases), the demographic characteristics and underlying diseases were not different. In addition, the clinical manifestations associated with atypical pneumonia, including headache (71.2% vs. 81.4%, p=0.255), sore throat (8.5% vs. 16.3%, p=0.351), cough (35.6% vs. 23.3%, p=0.199), and chest x-ray suggesting pneumonia (19.3% vs. 9.5%, p=0.258), were unchanged between the two groups. Clinicians should be aware of the high seroprevalence of M. pneumoniae IgM in acute Q fever, particularly with ELISA kits, which can lead to misdiagnosis, overestimations of the prevalence of M. pneumoniae pneumonia, and underestimations of the true prevalence of Q fever pneumonia. PMID:24147043
Chao, Chien-Chung; Belinskaya, Tatyana; Zhang, Zhiwen; Ching, Wei-Mei
2015-01-01
Sensitive, specific and rapid diagnostic tests for the detection of Orientia tsutsugamushi (O. tsutsugamushi) and Rickettsia typhi (R. typhi), the causative agents of scrub typhus and murine typhus, respectively, are necessary to accurately and promptly diagnose patients and ensure that they receive proper treatment. Recombinase polymerase amplification (RPA) assays using a lateral flow test (RPA-nfo) and real-time fluorescent detection (RPA-exo) were developed targeting the 47-kDa gene of O. tsutsugamushi or 17 kDa gene of R. typhi. The RPA assay was capable of detecting O. tsutsugamushi or R. typhi at levels comparable to that of the quantitative PCR method. Both the RPA-nfo and RPA-exo methods performed similarly with regards to sensitivity when detecting the 17 kDa gene of R. typhi. On the contrary, RPA-exo performed better than RPA-nfo in detecting the 47 kDa gene of O. tsutsugamushi. The clinical performance of the O. tsutsugamushi RPA assay was evaluated using either human patient samples or infected mouse samples. Eight out of ten PCR confirmed positives were determined positive by RPA, and all PCR confirmed negative samples were negative by RPA. Similar results were obtained for R. typhi spiked patient sera. The assays were able to differentiate O. tsutsugamushi and R. typhi from other phylogenetically related bacteria as well as mouse and human DNA. Furthermore, the RPA-nfo reaction was completed in 20 minutes at 37°C followed by a 10 minute incubation at room temperature for development of an immunochromatographic strip. The RPA-exo reaction was completed in 20 minutes at 39°C. The implementation of a cross contamination proof cassette to detect the RPA-nfo fluorescent amplicons provided an alternative to regular lateral flow detection strips, which are more prone to cross contamination. The RPA assays provide a highly time-efficient, sensitive and specific alternative to other methods for diagnosing scrub typhus or murine typhus.
Chao, Chien-Chung; Belinskaya, Tatyana; Zhang, Zhiwen; Ching, Wei-Mei
2015-01-01
Sensitive, specific and rapid diagnostic tests for the detection of Orientia tsutsugamushi (O. tsutsugamushi) and Rickettsia typhi (R. typhi), the causative agents of scrub typhus and murine typhus, respectively, are necessary to accurately and promptly diagnose patients and ensure that they receive proper treatment. Recombinase polymerase amplification (RPA) assays using a lateral flow test (RPA-nfo) and real-time fluorescent detection (RPA-exo) were developed targeting the 47-kDa gene of O. tsutsugamushi or 17 kDa gene of R. typhi. The RPA assay was capable of detecting O. tsutsugamushi or R. typhi at levels comparable to that of the quantitative PCR method. Both the RPA-nfo and RPA-exo methods performed similarly with regards to sensitivity when detecting the 17 kDa gene of R. typhi. On the contrary, RPA-exo performed better than RPA-nfo in detecting the 47 kDa gene of O. tsutsugamushi. The clinical performance of the O. tsutsugamushi RPA assay was evaluated using either human patient samples or infected mouse samples. Eight out of ten PCR confirmed positives were determined positive by RPA, and all PCR confirmed negative samples were negative by RPA. Similar results were obtained for R. typhi spiked patient sera. The assays were able to differentiate O. tsutsugamushi and R. typhi from other phylogenetically related bacteria as well as mouse and human DNA. Furthermore, the RPA-nfo reaction was completed in 20 minutes at 37oC followed by a 10 minute incubation at room temperature for development of an immunochromatographic strip. The RPA-exo reaction was completed in 20 minutes at 39oC. The implementation of a cross contamination proof cassette to detect the RPA-nfo fluorescent amplicons provided an alternative to regular lateral flow detection strips, which are more prone to cross contamination. The RPA assays provide a highly time-efficient, sensitive and specific alternative to other methods for diagnosing scrub typhus or murine typhus. PMID:26161793
Endemic Scrub Typhus-like Illness, Chile
2011-09-01
from Asia. The primary hosts for Rickettsia species are arthropods that can also act as disease vectors for humans and other vertebrates. Ticks...are vectors for most rickettsioses caused by spotted fever group rickettsiae . Alternative vectors for rickettsiae are well known, including fl eas as...sample recovered from a paraffi n- embedded sample for electron microscopy, showed round and oval rickettsia -like microorganisms, maximum diameter
2007-01-01
periphery of the lake grows emergent aquatic vegetation such as typhus and different sedge varieties. 3.2.2 Aquatic/Fishery Resources 3.2.2.1...that 98.1 percent of Eielson native wetlands are of low quality. Most of these wetlands are classified as black spruce or alder/willow scrub /shrub
STUDIES ON SCRUB TYPHUS (TSUTSUGAMUSHI DISEASE)
Rights, Fred L.; Smadel, Joseph E.
1948-01-01
Antigenic differences among strains of R. tsutsugamushi are sufficiently great that vaccines prepared from certain strains fail to induce resistance in mice to infection with other strains. Although the results of cross-vaccination tests indicate varying degrees of relationship between a number of the strains, there is no correlation between source of the rickettsia and antigenic pattern of the agent. PMID:18904219
Unsworth, Nathan B.; Graves, Stephen R.; Faa, Antony G.; Cox, G. Erika; Dyer, John R.; Boutlis, Craig S.; Lane, Amanda M.; Shaw, Matthew D.; Robson, Jennifer; Nissen, Michael D.
2007-01-01
Australia has 4 rickettsial diseases: murine typhus, Queensland tick typhus, Flinders Island spotted fever, and scrub typhus. We describe 7 cases of a rickettsiosis, with an acute onset and symptoms of fever (100%), headache (71%), arthralgia (43%), myalgia (43%), cough (43%), maculopapular/petechial rash (43%), nausea (29%), pharyngitis (29%), lymphadenopathy (29%), and eschar (29%). Cases were most prevalent in autumn and from eastern Australia, including Queensland, Tasmania, and South Australia. One patient had a history of tick bite (Haemaphysalis novaeguineae). An isolate shared 99.2%, 99.8%, 99.8%, 99.9%, and 100% homology with the 17 kDa, ompA, gltA, 16S rRNA, and Sca4 genes, respectively, of Rickettsia honei. This Australian rickettsiosis has similar symptoms to Flinders Island spotted fever, and the strain is genetically related to R. honei. It has been designated the “marmionii” strain of R. honei, in honor of Australian physician and scientist Barrie Marmion. PMID:17553271
Unsworth, Nathan B; Stenos, John; Graves, Stephen R; Faa, Antony G; Cox, G Erika; Dyer, John R; Boutlis, Craig S; Lane, Amanda M; Shaw, Matthew D; Robson, Jennifer; Nissen, Michael D
2007-04-01
Australia has 4 rickettsial diseases: murine typhus, Queensland tick typhus, Flinders Island spotted fever, and scrub typhus. We describe 7 cases of a rickettsiosis with an acute onset and symptoms of fever (100%), headache (71%), arthralgia (43%), myalgia (43%), cough (43%), maculopapular/petechial rash (43%), nausea (29%), pharyngitis (29%), lymphadenopathy (29%), and eschar (29%). Cases were most prevalent in autumn and from eastern Australia, including Queensland, Tasmania, and South Australia. One patient had a history of tick bite (Haemaphysalis novaeguineae). An isolate shared 99.2%, 99.8%, 99.8%, 99.9%, and 100% homology with the 17 kDa, ompA, gltA, 16S rRNA, and Sca4 genes, respectively, of Rickettsia honei. This Australian rickettsiosis has similar symptoms to Flinders Island spotted fever, and the strain is genetically related to R. honei. It has been designated the "marmionii" strain of R. honei, in honor of Australian physician and scientist Barrie Marmion.
Arthropod Borne Disease: The Leading Cause of Fever in Pregnancy on the Thai-Burmese Border
McGready, Rose; Ashley, Elizabeth A.; Wuthiekanun, Vanaporn; Tan, Saw Oo; Pimanpanarak, Mupawjay; Viladpai-nguen, Samuel Jacher; Jesadapanpong, Wilarat; Blacksell, Stuart D.; Peacock, Sharon J.; Paris, Daniel H.; Day, Nicholas P.; Singhasivanon, Pratap; White, Nicholas J.; Nosten, François
2010-01-01
Background Fever in pregnancy is dangerous for both mother and foetus. In the 1980's malaria was the leading cause of death in pregnant women in refugee camps on the Thai-Burmese border. Artemisinin combination therapy has significantly reduced the incidence of malaria in the population. The remaining causes of fever in pregnancy are not well documented. Methodology Pregnant women attending antenatal care, where weekly screening for malaria is routine, were invited to have a comprehensive clinical and laboratory screen if they had fever. Women were admitted to hospital, treated and followed up weekly until delivery. A convalescent serum was collected on day 21. Delivery outcomes were recorded. Principal Findings Febrile episodes (n = 438) occurred in 5.0% (409/8,117) of pregnant women attending antenatal clinics from 7-Jan-2004 to 17-May-2006. The main cause was malaria in 55.5% (227/409). A cohort of 203 (49.6% of 409) women had detailed fever investigations and follow up. Arthropod-borne (malaria, rickettsial infections, and dengue) and zoonotic disease (leptospirosis) accounted for nearly half of all febrile illnesses, 47.3% (96/203). Coinfection was observed in 3.9% (8/203) of women, mostly malaria and rickettsia. Pyelonephritis, 19.7% (40/203), was also a common cause of fever. Once malaria, pyelonephritis and acute respiratory illness are excluded by microscopy and/or clinical findings, one-third of the remaining febrile infections will be caused by rickettsia or leptospirosis. Scrub and murine typhus were associated with poor pregnancy outcomes including stillbirth and low birth weight. One woman died (no positive laboratory tests). Conclusion/Significance Malaria remains the leading cause of fever in pregnancy on the Thai-Burmese border. Scrub and murine typhus were also important causes of fever associated with poor pregnancy outcomes. Febrile pregnant women on the Thai-Burmese border who do not have malaria, pyelonephritis or respiratory tract infection should be treated with azithromycin, effective for typhus and leptospirosis. PMID:21103369
Arthropod borne disease: the leading cause of fever in pregnancy on the Thai-Burmese border.
McGready, Rose; Ashley, Elizabeth A; Wuthiekanun, Vanaporn; Tan, Saw Oo; Pimanpanarak, Mupawjay; Viladpai-Nguen, Samuel Jacher; Jesadapanpong, Wilarat; Blacksell, Stuart D; Peacock, Sharon J; Paris, Daniel H; Day, Nicholas P; Singhasivanon, Pratap; White, Nicholas J; Nosten, François
2010-11-16
Fever in pregnancy is dangerous for both mother and foetus. In the 1980's malaria was the leading cause of death in pregnant women in refugee camps on the Thai-Burmese border. Artemisinin combination therapy has significantly reduced the incidence of malaria in the population. The remaining causes of fever in pregnancy are not well documented. Pregnant women attending antenatal care, where weekly screening for malaria is routine, were invited to have a comprehensive clinical and laboratory screen if they had fever. Women were admitted to hospital, treated and followed up weekly until delivery. A convalescent serum was collected on day 21. Delivery outcomes were recorded. Febrile episodes (n = 438) occurred in 5.0% (409/8,117) of pregnant women attending antenatal clinics from 7-Jan-2004 to 17-May-2006. The main cause was malaria in 55.5% (227/409). A cohort of 203 (49.6% of 409) women had detailed fever investigations and follow up. Arthropod-borne (malaria, rickettsial infections, and dengue) and zoonotic disease (leptospirosis) accounted for nearly half of all febrile illnesses, 47.3% (96/203). Coinfection was observed in 3.9% (8/203) of women, mostly malaria and rickettsia. Pyelonephritis, 19.7% (40/203), was also a common cause of fever. Once malaria, pyelonephritis and acute respiratory illness are excluded by microscopy and/or clinical findings, one-third of the remaining febrile infections will be caused by rickettsia or leptospirosis. Scrub and murine typhus were associated with poor pregnancy outcomes including stillbirth and low birth weight. One woman died (no positive laboratory tests). Malaria remains the leading cause of fever in pregnancy on the Thai-Burmese border. Scrub and murine typhus were also important causes of fever associated with poor pregnancy outcomes. Febrile pregnant women on the Thai-Burmese border who do not have malaria, pyelonephritis or respiratory tract infection should be treated with azithromycin, effective for typhus and leptospirosis.
Rickettsial Infections and Fever, Vientiane, Laos
Phongmany, Simaly; Rolain, Jean-Marc; Phetsouvanh, Rattanaphone; Blacksell, Stuart D.; Soukkhaseum, Vimone; Rasachack, Bouachanh; Phiasakha, Khamphong; Soukkhaseum, Surn; Frichithavong, Khamthavi; Chu, Vang; Keolouangkhot, Valy; Martinez-Aussel, Bertrand; Chang, Ko; Darasavath, Chirapha; Rattanavong, Oudayvone; Sisouphone, Siho; Mayxay, Mayfong; Vidamaly, Sisouphane; Parola, Philippe; Thammavong, Chanpheng; Heuangvongsy, Mayboun; Syhavong, Bounkong; Raoult, Didier; White, Nicholas J.
2006-01-01
Rickettsial diseases have not been described previously from Laos, but in a prospective study, acute rickettsial infection was identified as the cause of fever in 115 (27%) of 427 adults with negative blood cultures admitted to Mahosot Hospital in Vientiane, Laos. The organisms identified by serologic analysis were Orientia tsutsugamushi (14.8%), Rickettsia typhi (9.6%), and spotted fever group rickettsia (2.6% [8 R. helvetica, 1 R. felis, 1 R. conorii subsp. indica, and 1 Rickettsia "AT1"]). Patients with murine typhus had a lower frequency of peripheral lymphadenopathy than those with scrub typhus (3% vs. 46%, p<0.001). Rickettsioses are an underrecognized cause of undifferentiated febrile illnesses among adults in Laos. This finding has implications for the local empiric treatment of fever. PMID:16494751
Chen, Hua-Wei; Zhang, Zhiwen; Huber, Erin; Mutumanje, Elissa; Chao, Chien-Chung; Ching, Wei-Mei
2011-06-01
Western blot analysis of Orientia tsutsugamushi whole-cell lysates with scrub typhus patient sera has identified at least five protein antigens of O. tsutsugamushi with molecular sizes of 22 kDa, 47 kDa, 56 kDa, 58 kDa, and 110 kDa. In this study, sera from serial bleedings of 108 patients were used to study the kinetics and the magnitude of specific antibody responses against the 47-kDa and 56-kDa antigens. Recombinant protein of the conserved 47-kDa antigen (r47b) or a mixture of truncated 56-kDa antigen (r56s) from three prototype strains was used as the antigen in an enzyme-linked immunosorbent assay (ELISA). Our results showed that 76% and 93% of these patients had elevated IgM and IgG against r47b, respectively, and 98% and 100% had elevated IgM and IgG against r56s, respectively. The kinetics of antibody responses against r47b and r56s can be grouped into three patterns. In the first type of response, IgM and IgG against r47b and r56s appeared about the same time. The IgM and IgG titers against r56s were much higher than those against r47b. In the second type of response, induction of IgM appeared to be similar to that in the first type. The major difference to the first type is that the IgG titers against r47b were induced at least 1 week later than those against the r56s. The third type showed strong IgG responses against both r47b and r56s, and low or no IgM responses indicated a secondary infection. This is the first systematic investigation of antibody response kinetics against the conserved 47-kDa antigen versus the variable 56-kDa antigen in scrub typhus patients.
Rickettsial infection among military personnel deployed in Northern Sri Lanka.
Premaratna, Ranjan; Ariyaratna, Nimalka; Attanayake, Champaka; Bandara, Wijesinghe; Chandrasena, Nilmini; de Silva, H Janaka
2014-12-20
Military personnel deployed in field actvities report on frequent tick bites. Therefore they may run the risk of exposure to rickettsial organisms. In order to assess the risk of exposure to rickettsial organisms, two groups of military personnel who were deployed in field activities of Nothern Sri Lanka were investigated. The first group was studied in order to assess the sero-prevalence of rickettsioses and consisted of soldiers who were admitted following injuries during field activities. The second group was studied to identify the incidence of acute rickettsioses during their acute febrile presentations. They were tested with IFA-IgG against spotted fever group rickettsioses (SFG), scrub typhus (ST) and murine typhus. In the first group, 48/57 (84%) military personnel had serological evidence of exposure to rickettsioses (in all, IFA-IgG titer ≥ 1:128): 33/50 (66%) to SFG rickettsioses, 1/50 (2%) to ST and 14/50 (28%) had mixed titers for both (in all, titers were higher for SFG). While all of them were in military uniform most of the time and frequently slept on scrub land, 35/57 (61.4%) had never used insect repellents and none were on doxycycline prophylaxis. 48/57 (84%) had experienced tick bites during field activity. In the second group, there were 49 who presented with acute febrile illness with a mean duration of 8.5 days (SD 3.2). 33/49 (67.3%) were serologically positive for acute rickettsioses (IgG ≥1:256); 26 (79%) due to ST and 7 (21%) due to SFG rickettsioses, Exposure to rickettsial disease was common among soldiers who were deployed in Northern Sri Lanka. Scrub typhus was the predominent species accounting for acute febrile illness. Further studies are needed to understand the reasons for very high sero-prevalence for SFG rickettsioses with no anticedent febrile illness. Use of preventive measures was not satisfactory. The high sero-prevelence of SFG rickettsioses is likely to interfere with serological diagnosis of acute SFG rickettsioses in this population.
A case of typhoidal tularemia in a male Japanese farmer.
Nakamura, Kiwamu; Fujita, Hiromi; Miura, Tomoya; Igata, Yu; Narita, Masashi; Monma, Naota; Hara, Yasuka; Saito, Kyoichi; Matsumoto, Akinori; Kanemitsu, Keiji
2018-06-01
In Japan, most tularemia cases occur after contact with hares (hunting, cooking) and involve the glandular or ulceroglandular form. Here, we present a case of typhoidal tularemia in a 72-year-old Japanese male farmer who presented with fever, fatigue, and right lower abdominal pain. Computed tomography revealed intestinal wall thickening at the ascending colon, pleural effusion, and ascites. Following an initial diagnosis of bacterial enteric infection, his symptoms deteriorated after a week-long cephalosporin treatment course. The patient lived in an area endemic for scrub typhus; the antibiotic was changed to a tetracycline on suspicion of scrub typhus infection. His symptoms rapidly improved after initiation of minocycline treatment. Later, blood tests revealed marked increases in serological tests against Francisella tularensis exclusively, and the patient was diagnosed with typhoidal tularemia. Typhoidal tularemia may be characterized by any combination of general symptoms, but does not exhibit the local manifestations associated with other forms of tularemia. The patient, in this case, had no direct contact with hares or other wild animals and did not present with local manifestations of tularemia. Physicians should consider this disease, especially when tick-borne disease is suspected in the absence of local wounds, eschar, ulcers, or lymphadenopathy. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Lubell, Yoel; Althaus, Thomas; Blacksell, Stuart D.; Paris, Daniel H.; Mayxay, Mayfong; Pan-Ngum, Wirichada; White, Lisa J.; Day, Nicholas P. J.; Newton, Paul N.
2016-01-01
Background Malaria accounts for a small fraction of febrile cases in increasingly large areas of the malaria endemic world. Point-of-care tests to improve the management of non-malarial fevers appropriate for primary care are few, consisting of either diagnostic tests for specific pathogens or testing for biomarkers of host response that indicate whether antibiotics might be required. The impact and cost-effectiveness of these approaches are relatively unexplored and methods to do so are not well-developed. Methods We model the ability of dengue and scrub typhus rapid tests to inform antibiotic treatment, as compared with testing for elevated C-Reactive Protein (CRP), a biomarker of host-inflammation. Using data on causes of fever in rural Laos, we estimate the proportion of outpatients that would be correctly classified as requiring an antibiotic and the likely cost-effectiveness of the approaches. Results Use of either pathogen-specific test slightly increased the proportion of patients correctly classified as requiring antibiotics. CRP testing was consistently superior to the pathogen-specific tests, despite heterogeneity in causes of fever. All testing strategies are likely to result in higher average costs, but only the scrub typhus and CRP tests are likely to be cost-effective when considering direct health benefits, with median cost per disability adjusted life year averted of approximately $48 USD and $94 USD, respectively. Conclusions Testing for viral infections is unlikely to be cost-effective when considering only direct health benefits to patients. Testing for prevalent bacterial pathogens can be cost-effective, having the benefit of informing not only whether treatment is required, but also as to the most appropriate antibiotic; this advantage, however, varies widely in response to heterogeneity in causes of fever. Testing for biomarkers of host inflammation is likely to be consistently cost-effective despite high heterogeneity, and can also offer substantial reductions in over-use of antimicrobials in viral infections. PMID:27027303
Lai, C-H; Sun, W; Lee, C-H; Lin, J-N; Liao, M-H; Liu, S-S; Chang, T-Y; Tsai, K-F; Chang, Y-C; Lin, H-H; Chen, Y-H
2017-11-01
Q fever (QF) is a worldwide zoonosis associated with outbreaks. Only a few nationwide studies regarding the surveillance and epidemiology of human QF have been reported. Although QF is endemic in Taiwan, a nationwide database investigation of the epidemiology and characteristics of QF and its associations with scrub typhus (ST), murine typhus (MT) and leptospirosis (LS) has never been reported. We analysed nationwide databases of suspected QF, ST, MT and LS cases from October 2007 to December 2014 obtained from the Centers for Disease Control, Taiwan. A total of 468 (4.2%) QF cases were identified among 11 109 suspected QF cases. QF cases were mainly distributed in the southern and Kaohsiung-Pingtung regions but rarely in the eastern region. Compared to non-QF cases, QF cases had significantly higher percentages of males (88.7 versus 66.2%) and high-risk occupations (farming, animal husbandry or veterinary medicine) (16.2 versus 10.5%). But the percentages of specific animal contact, including cattle (0.6 versus 0.8%) and goats (0.9 versus 1.0%), were low in both. The majority of suspected QF cases (89.4%) were simultaneously suspected with ST, MT or LS, and the combinations of suspected diseases differed between regions. The number of suspected QF cases from the eastern region decreased since 2009, which was not observed in other regions. A total of 1420 (12.8%) cases had confirmed diseases, including QF (453, 4.1%), QF+ST (7, 0.06%), QF+MT (4, 0.04%), QF+LS (4, 0.04%), MT (186, 1.7%), ST (545, 4.9%), ST+LS (11, 0.1%) and LS (210, 1.9%). Compared to cases of unknown disease, QF cases had larger percentages of high-risk occupations (16.2 versus 9.6%) but similar histories of animal contact (29.8 versus 25.1%). QF is an endemic disease in southern Taiwan. It is difficult to differentiate QF from ST, MT or LS only by high-risk occupations and history of animal contact, and co-infection of QF with these diseases should be considered. © 2016 Blackwell Verlag GmbH.
Isolation of a Novel Orientia Species ( O. chuto sp. nov.) from a Patient Infected in Dubai
2010-12-01
the genus Rickettsia , the organism Rickettsia tsutsugamushi was reclassified under the new genus Orientia and was renamed Orientia tsutsuga- mushi gen...tests for a number of pathogens were performed and showed a positive total antibody titer of 1:512 for scrub typhus group (STG) rickettsia by...noticeably reduced. By day 42, the patient reported feeling markedly better, although still quite lethargic. STG rickettsia serology titer peaked at
2011-01-01
Rickettsia typhi and TT118 spotted fever group rickettsiae among Malaysian blood donors and febrile patients in the urban areas . Southeast Asian J...Jackson EB , 1948 . Studies on scrub typhus (tsutsugamushi disease). Part III: Heterogeneity of strains of Rickettsia tsutsugamushi as...specific and crossreactive lymphocyte proliferative responses during chronic immunizing infections with Rickettsia tsutsugamushi . Infect Immun 40
Hemorrhagic Fever with Renal Syndrome (Korean Hemorrhagic Fever)
1990-06-29
particles were used for a rapid serologic diagnostic test for HFRS. ’te-re were 430 cases of HFRS in Korea in 1989 and large outbreaks of scrub typhus...almost same as in 1988. A simple and rapid serologic diagnostic test for hantavirus infection was developed by high density particle agglutination...infection and HFRS b) serologic relation cif hantaviruses isolated from the different parts of the world c) development of a simple serologic diagnostic
Frances, Stephen P; Edstein, Michael D; Debboun, Mustapha; Shanks, G Dennis
2016-01-01
Australian and US military medical services have collaborated since World War II to minimize vector-borne diseases such as malaria, dengue, and scrub typhus. In this review, collaboration over the last 30 years is discussed. The collaborative projects and exchange scientist programs have resulted in mutually beneficial outcomes in the fields of drug development and personal protection measures against vector-borne diseases.
Park, Gab-Man; Shin, Ho-Sung
2016-04-01
The geographical distributions and relative population densities of scrub typhus vector mites collected from small mammals were determined for 5 locations on the east coast of the Republic of Korea. Collection sites included Goseong, Gangneung, and Hoengseong in Gangwon province and Uljin and Yeongdeok in Gyeongbuk province. A total of 275 small mammals including members of Rodentia (rodents) and Soricomorpha (shrews, such as Crocidura lasiura ) belonging to 4 genera and 4 species were captured in the field from 2012 to 2013. Apodemus agrarius was collected most frequently (220, 80%), followed by C. lasiura (25, 9.1%), Mus musculus (15, 5.5%), and Myodes regulus (15, 5.5%). A total of 23,436 larval chigger mites (Family Trombiculidae) belonging to 3 genera and 8 species (Leptotrombidium pallidum, Leptotrombidium scutellare, Leptotrombidium palpale, Leptotrombidium orientale, Leptotrombidium zetum, Neotrombicula tamiyai, Neotrombicula japonica, and Euschoengastica koreaensis) were collected from the small mammals. The predominant chigger species collected during the spring and fall seasons from A. agrarius were L. pallidum (57.6%), L. palpale (14.5%), and L. scutellare (7.9%). Leptotrombidium scutellare was collected only along the southeastern coast at Yeongdeok, Gyeongbuk province. The geographical distribution of scrub typhus vectors and reservoir hosts are important aspects of understanding the epidemiology of the disease as well as the potential impacts of climate change and health risks.
The infective causes of hepatitis and jaundice amongst hospitalised patients in Vientiane, Laos
Syhavong, Bounkong; Rasachack, Bouachanh; Smythe, Lee; Rolain, Jean-Marc; Roque-Afonso, Anne-Marie; Jenjaroen, Kemajittra; Soukkhaserm, Vimone; Phongmany, Simmaly; Phetsouvanh, Rattanaphone; Soukkhaserm, Sune; Thammavong, Te; Mayxay, Mayfong; Blacksell, Stuart D.; Barnes, Eleanor; Parola, Philippe; Dussaix, Elisabeth; Raoult, Didier; Humphreys, Isla; Klenerman, Paul; White, Nicholas J.; Newton, Paul N.
2010-01-01
Summary There is little information on the diverse infectious causes of jaundice and hepatitis in the Asiatic tropics. Serology (hepatitis A, B, C and E, leptospirosis, dengue, rickettsia), antigen tests (dengue), PCR assays (hepatitis A, C and E) and blood cultures (septicaemia) were performed on samples from 392 patients admitted with jaundice or raised transaminases (≥ × 3) to Mahosot Hospital, Vientiane, Laos over 3 years. Conservative definitions suggested diagnoses of dengue (8.4%), rickettsioses (7.3%), leptospirosis (6.8%), hepatitis B (4.9%), hepatitis C (4.9%), community-acquired septicaemia (3.3%) and hepatitis E (1.6%). Although anti-hepatitis A virus (HAV) IgM antibody results suggested that 35.8% of patients had acute HAV infections, anti-HAV IgG antibody avidity and HAV PCR suggested that 82% had polyclonal activation and not acute HAV infections. Scrub typhus, murine typhus or leptospirosis were present in 12.8% of patients and were associated with meningism and relatively low AST and ALT elevation. These patients would be expected to respond to empirical doxycycline therapy which, in the absence of virological diagnosis and treatment, may be an appropriate cost-effective intervention in Lao patients with jaundice/hepatitis. PMID:20378138
Ecological considerations in scrub typhus*
Traub, Robert; Wisseman, Charles L.
1968-01-01
Certain features, characteristic of outbreaks of scrub typhus, can be explained by the behaviour of the chigger vectors which are remarkably hardy and can survive weeks of freezing or immersion in water. The established vectors are all species of the genus Leptotrombidium (Leptotrombidium), i.e., L. (L.) akamushi (Brumpt, 1910), L. (L.) deliense (Walch, 1922), L. (L.) pallidum (Nagayo et al., 1919), and L. (L.) scutellare (Nagayo et al., 1921). These chiggers (i.e. larval mites) infest a broad variety of birds and mammals, and tend to be found in clusters on certain specific sites on the host. However, the precise site for any species of mite varies with the host, and it is believed that the grooming habits of the infested animal account for this “site preference”. The degree of infestation cannot validly be ascribed to the size of the host. L. (L.) pavlovskyi (Schluger, 1948), L. (L.) orientale (Schluger, 1948), L. (L.) arenicola Traub, 1960, and L. (L.) tosa (Sasa & Kowashima, 1951) are regarded as probable vectors. Other species, some belonging to other genera, are under suspicion in this regard. L. (L.) subintermedium (Jameson & Toshioka, 1954) and certain other chiggers were found in “ecological islands” in all montane habitats studied in West Pakistan, despite the intervening high mountains, broad rivers and belts of semi-desert. The infection-rate of Rickettsia tsutsugamushi in vector species in nature is believed to be low, and chiggers may be serving as reservoirs of infection and not just as vectors. PMID:5303405
2014-01-01
Background Leptotrombidium pallidum and Leptotrombidium scutellare are the major vector mites for Orientia tsutsugamushi, the causative agent of scrub typhus. Before these organisms can be subjected to whole-genome sequencing, it is necessary to estimate their genome sizes to obtain basic information for establishing the strategies that should be used for genome sequencing and assembly. Method The genome sizes of L. pallidum and L. scutellare were estimated by a method based on quantitative real-time PCR. In addition, a k-mer analysis of the whole-genome sequences obtained through Illumina sequencing was conducted to verify the mutual compatibility and reliability of the results. Results The genome sizes estimated using qPCR were 191 ± 7 Mb for L. pallidum and 262 ± 13 Mb for L. scutellare. The k-mer analysis-based genome lengths were estimated to be 175 Mb for L. pallidum and 286 Mb for L. scutellare. The estimates from these two independent methods were mutually complementary and within a similar range to those of other Acariform mites. Conclusions The estimation method based on qPCR appears to be a useful alternative when the standard methods, such as flow cytometry, are impractical. The relatively small estimated genome sizes should facilitate whole-genome analysis, which could contribute to our understanding of Arachnida genome evolution and provide key information for scrub typhus prevention and mite vector competence. PMID:24947244
2011-01-01
pended in M199 medium (Grand Island Biological Company [GIBCO), Grand Island, NY), and subsequently exposed to 3,000-rad irradiation in 60Co gamma... irradiator (Atomic Energy of Canada, Ltd., Ottawa, Canada). Irradiated L-929 cells were dispensed into three 50-cm2 flasks to develop a monolayer...monolayers of irradiated L-929 cells. Inoculated cells were incubated at room temperature for 1 hour on a shaker and then the BHI supernatant was dis
Tanskul, P; Linthicum, K J
1997-05-01
Leptotrombidium (Leptotrombidium) chiangraiensis Tanskul & Linthicum is described and illustrated as new from specimens collected from the rodents Rattus rattus (L., 1758), Rattus argentiventer (Robinson & Kloss, 1916), Rattus losea (Swinhoe, 1870), and Bandicota indica (Bechstein, 1800) in Chiangrai Province northern Thailand. The new species was collected in active rice fields and adjacent fruit plantation areas. The etiological agent of scrub typhus, Orientia (formerly Rickettsia) tsutsugamushi (Hayashi), has been isolated from patients who live and work in the same habitat where L. chiangraiensis is the predominant Leptotrombidium species.
Comparison of Preferred Bite Sites between Mites and Ticks on Humans in Korea
Jang, Mi-Sun; Kim, Choon-Mee; Kim, Dong-Min; Yoon, Na Ra; Han, Mi Ah; Kim, Hyun-Kuk; Oh, Won Sup; Yoon, Hee-Jung; Wie, Seong-Heon; Hur, Jian
2016-01-01
Identification of mite and tick bite sites provides important clinical information. The predominant mite species in Korea associated with scrub typhus are Leptotrombidium pallidum and Leptotrombidium scutellare. The most abundant tick species is Haemaphysalis longicornis. To date, there has been no comparative study on preferred bite sites between mites and ticks in humans. This study included a review of medical records and a field study. For mite bite sites, eschars were checked on 506 patients with scrub typhus, confirmed by indirect immunofluorescence assay or nested polymerase chain reaction on the 56-kDa type-specific antigen gene of Orientia tsutsugamushi. Tick bite sites were identified and marked on a diagram for 91 patients who experienced tick bites within the previous year through a field epidemiological investigation. The mite and tick bite sites in Koreans were compared. The most frequently observed mite bite sites were the anterior chest, including the axillae (29.1%) and the abdominal region, including the inguinal area (26.1%). Tick bite sites were most frequent on the lower extremities (33.0%), followed by the abdominal region, including the inguinal area (26.4%), and upper extremities (26.4%). The distribution was significantly different between mite and tick bite sites (P < 0.001). There was a statistically significant difference in the mite bite (P = 0.001), but not tick bite sites (P = 0.985), between men and women. This is the first report on the differences between tick and mite bite sites, and may help clinicians reach a rapid diagnosis of mite- or tick-borne infection. PMID:27645781
Jensenius, Mogens; Han, Pauline V.; Schlagenhauf, Patricia; Schwartz, Eli; Parola, Philippe; Castelli, Francesco; von Sonnenburg, Frank; Loutan, Louis; Leder, Karin; Freedman, David O.
2013-01-01
We performed a descriptive analysis of acute and potentially life-threatening tropical diseases among 82,825 ill western travelers reported to GeoSentinel from June of 1996 to August of 2011. We identified 3,655 patients (4.4%) with a total of 3,666 diagnoses representing 13 diseases, including falciparum malaria (76.9%), enteric fever (18.1%), and leptospirosis (2.4%). Ninety-one percent of the patients had fever; the median time from travel to presentation was 16 days. Thirteen (0.4%) patients died: 10 with falciparum malaria, 2 with melioidosis, and 1 with severe dengue. Falciparum malaria was mainly acquired in West Africa, and enteric fever was largely contracted on the Indian subcontinent; leptospirosis, scrub typhus, and murine typhus were principally acquired in Southeast Asia. Western physicians seeing febrile and recently returned travelers from the tropics need to consider a wide profile of potentially life-threatening tropical illnesses, with a specific focus on the most likely diseases described in our large case series. PMID:23324216
Anitharaj, Velmurugan; Stephen, Selvaraj; Pradeep, Jothimani; Pooja, Pratheesh; Preethi, Sridharan
2017-01-01
Background: In the recent past, scrub typhus (ST) has been reported from different parts of India, based on Weil-Felix/enzyme-linked immunosorbent assay (ELISA)/indirect immunofluorescence assay (IFA). Molecular tests are applied only by a few researchers. Aims: Evaluation of a new commercial real time polymerase chain reaction (PCR) kit for molecular diagnosis of ST by comparing it with the commonly used IgM ELISA is our aim. Settings and Design: ST has been reported all over India including Puducherry and surrounding Tamil Nadu and identified as endemic for ST. This study was designed to correlate antibody detection by IgM ELISA and Orientia tsutsugamushi DNA in real time PCR. Materials and Methods: ST IgM ELISA (InBios Inc., USA) was carried out for 170 consecutive patients who presented with the symptoms of acute ST during 11 months (November, 2015– September, 2016). All 77 of these patients with IgM ELISA positivity and 49 of 93 IgM ELISA negative patients were subjected to real time PCR (Geno-Sen's ST real time PCR, Himachal Pradesh, India). Statistical Analysis: Statistical analysis for clinical and laboratory results was performed using IBM SPSS Statistics 17 for Windows (SPSS Inc., Chicago, USA). Chi-square test with Yates correction (Fisher's test) was employed for a small number of samples. Results and Conclusion: Among 77 suspected cases of acute ST with IgM ELISA positivity and 49 IgM negative patients, 42 and 7 were positive, respectively, for O. tsutsugamushi 56-kDa type-specific gene in real time PCR kit. Until ST IFA, the gold standard diagnostic test, is properly validated in India, diagnosis of acute ST will depend on both ELISA and quantitative PCR. PMID:28878522
Anitharaj, Velmurugan; Stephen, Selvaraj; Pradeep, Jothimani; Pooja, Pratheesh; Preethi, Sridharan
2017-01-01
In the recent past, scrub typhus (ST) has been reported from different parts of India, based on Weil-Felix/enzyme-linked immunosorbent assay (ELISA)/indirect immunofluorescence assay (IFA). Molecular tests are applied only by a few researchers. Evaluation of a new commercial real time polymerase chain reaction (PCR) kit for molecular diagnosis of ST by comparing it with the commonly used IgM ELISA is our aim. ST has been reported all over India including Puducherry and surrounding Tamil Nadu and identified as endemic for ST. This study was designed to correlate antibody detection by IgM ELISA and Orientia tsutsugamushi DNA in real time PCR. ST IgM ELISA (InBios Inc., USA) was carried out for 170 consecutive patients who presented with the symptoms of acute ST during 11 months (November, 2015- September, 2016). All 77 of these patients with IgM ELISA positivity and 49 of 93 IgM ELISA negative patients were subjected to real time PCR (Geno-Sen's ST real time PCR, Himachal Pradesh, India). Statistical analysis for clinical and laboratory results was performed using IBM SPSS Statistics 17 for Windows (SPSS Inc., Chicago, USA). Chi-square test with Yates correction (Fisher's test) was employed for a small number of samples. Among 77 suspected cases of acute ST with IgM ELISA positivity and 49 IgM negative patients, 42 and 7 were positive, respectively, for O. tsutsugamushi 56-kDa type-specific gene in real time PCR kit. Until ST IFA, the gold standard diagnostic test, is properly validated in India, diagnosis of acute ST will depend on both ELISA and quantitative PCR.
Tsai, Kun-Hsien; Chang, Shu-Feng; Yen, Tsai-Ying; Shih, Wei-Liang; Chen, Wan-Jen; Wang, Hsi-Chieh; Yu, Xue-Jie; Wen, Tzai-Hung; Wu, Wen-Jer; Shu, Pei-Yun
2016-01-27
Tick-borne ehrlichiosis and mite-borne scrub typhus represent important emerging zoonotic rickettsial diseases. Although scrub typhus has been recognized by the Taiwanese public health system, information on ehrlichial infections is scarce in Taiwan. In this study, the risk of spread of ectoparasites on rodents through aerial and marine transportation was assessed in international and domestic harbors. Here, we report the first systematic surveillance of seroprevalence against Ehrlichia spp. in small mammals on the main island of Taiwan. In total, 1648 small mammals were trapped from 8 international ports, 18 domestic fishing harbors, and 7 local public health centers around Taiwan from November 2004 to December 2008. Sera were analyzed using indirect immunofluorescence assays to detect IgG antibodies against Ehrlichia chaffeensis and Orientia tsutsugamushi. A serum titer of ≧1:80 was considered positive. Antibodies against Ehrlichia spp. and O. tsutsugamushi were detected in 3.28% and 4.92% of small mammals active around harbors, respectively. The seropositive rate against Ehrlichia was higher in northern Taiwan from 2005 to 2008. However, O. tsutsugamushi infections increased in southern Taiwan during this period. The serological evidence of ehrlichial and O. tsutsugamushi infections in all international ports were included in the study. No significant differences were found among the seropositive rates of Ehrlichia spp. and O. tsutsugamushi in small mammals trapped between international and local harbors. The overall prevalence of Ehrlichia spp. and O. tsutsugamushi infections in small mammals active around harbors was 3.28% and 4.92%, respectively. The results provided serological evidence supporting the potential risks of transporting pathogens through air and maritime traffic. This study highlights serious issues of the emergence and spread of rickettsial diseases in Taiwan. The incidence of human ehrlichiosis requires further investigation.
Peng, Pei-Ying; Guo, Xian-Guo; Ren, Tian-Guang; Dong, Wen-Ge; Song, Wen-Yu
2016-05-01
Trombiculid mites (or chigger mites) are a large group of arthropods, and some of these species are vectors of Orientia tsutsugamushi, the causative agent of tsutsugamushi disease (scrub typhus). Yunnan Province is situated in the southwest of China, and its complicated topography, special altitude gradients, and high biodiversity have aroused the interest of many scientists to study the fauna and species diversity of plants and animals. To replenish our former faunal study, this paper listed all the scientific names of trombiculid mites in Yunnan Province, together with their hosts and collection sites (geographical distribution). A total of 120,138 individuals of trombiculid mites were collected from the body surface of 13,760 small mammal hosts (89.06 % of them are rodents) in 29 collection sites (counties) of Yunnan Province from 2001 to 2013. The 120,138 mites were identified as comprising 2 families (Trombiculidae and Leeuwenhoekiidae), 26 genera, and 274 species. The genus Leptotrombidium had the most abundant species (109 species) of 26 genera. Of the six main vectors of scrub typhus in China, five of them were found in Yunnan. Of the 274 chigger mite species, 23 were determined as the newly recorded species (new records), which were found in Yunnan Province for the first time. The identified 274 species of trombiculid mites in the present paper are much more than those from other provinces in China and even largely exceeded the species of trombiculid mites recorded from some other regions and countries in the world. Based on the formula of Chao 1, the total number of chigger mite species in Yunnan was approximately estimated to be 346 species, and about 72 species might have been missed in our sampling process.
Tanskul, P; Linthicum, K J
1999-01-01
Leptotrombidium (Leptotrombidium) imphalum Vercammen-Grandjean & Langston is redescribed and illustrated. Specimens were collected from the rodents Rattus rattus, Rattus losea, and Bandicota indica in Chiangrai Province, northern Thailand. The species was found on hosts collected on dikes at the margins of rice fields and in adjacent fruit plantations and along irrigation canals, especially in areas covered with the grasses Imperata cylindrica (lalang grass) and Saccharum arudinaceum. The etiological agent of scrub typhus, Orientia (formerly Rickettsia) tsutsugamushi has been isolated from L. (L.) imphalum, rodent hosts, and patients who live and work in the same habitats.
Rickettsiae and rickettsial diseases
Brezina, R.; Murray, E. S.; Tarizzo, M. L.; Bögel, K.
1973-01-01
This paper summarizes present knowledge on rickettsiae and rickettsial diseases, and on their epidemiological characteristics, control, and public health significance. There are many natural foci of rickettsial diseases, from where the disease may spread to other areas in the world under changing socioeconomic conditions. Because of rapid long-distance travel, sporadic cases of serious rickettsial diseases may today appear far from endemic areas where the infection occurred. Even in endemic areas the disease may be misdiagnosed and deaths may occur as a result of inadequate treatment. Rapid treatment of rickettsial infections (preferably with tetracyclines) is therefore most important. Epidemic louse-borne typhus, though no longer subject to the International Health Regulations, remains one of the diseases in the WHO epidemiological surveillance programme. This disease continues to be a major cause of morbidity and mortality in some parts of Africa and it is present also in parts of the Americas and of Asia. Scrub typhus remains a continuing and serious public health problem in areas of South-East Asia and in the Western Pacific. The annual number of reported cases of Rocky Mountain spotted fever in the USA showed an increase during the last two decades, which may be due to improved recognition as well as to increased outdoor activities and migration of people from the city centres to the suburbs. Related forms of tick-borne typhus occur in South America, the Mediterranean region, Africa, South-East Asia, the Far East, and the Western Pacific. Increasing in number, though still sporadic, are reports of serious illness from chronic Q fever infection in many parts of the world. PMID:4547297
Distribution of rats infected with Rickettsia tsutsugamushi (scrub typhus) in an edge habitat.
Muul, I; Chai, K S
1978-12-01
No focalization of rats (Rattus tiomanicus and R. argentiventer) infected with Rickettsia tsutsugamushi could be discerned over a 500 m trapping transect at the border between a forest and lalang grass (Imperata cylindrica). R. tiomanicus appeared to occupy 250 m of the transect on the average and had periods during which infections were observed which averaged 97 days. Calulations indicated that more than 50% of individuals become infected over their life-time. The high rate of infection in this and other areas described in earlier publications and the habits of the rats suggest that infected mites are densely and widely dispersed in the areas studied in Malaysia.
Ching, W.-M.; Wang, H.; Eamsila, C.; Kelly, D. J.; Dasch, G. A.
1998-01-01
The variable 56-kDa major outer membrane protein of Orientia tsutsugamushi is the immunodominant antigen in human scrub typhus infections. The gene encoding this protein from Karp strain was cloned into the expression vector pET11a. The recombinant protein (r56) was expressed as a truncated nonfusion protein (amino acids 80 to 456 of the open reading frame) which formed an inclusion body when expressed in Escherichia coli BL21. Refolded r56 was purified and compared to purified whole-cell lysate of the Karp strain of O. tsutsugamushi by immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) for reactivity with rabbit sera prepared against eight antigenic prototypes of O. tsutsugamushi as well as several other species of Rickettsiales and nonrickettsial antigens. Refolded r56 exhibited broad reactivity with the rabbit antisera against the Orientia prototypes, and the ELISA reactions with the r56 and Karp whole-cell lysate antigens correlated well (r = 0.81, n = 22, sensitivity compared to that of standard ELISA of 91%). Refolded r56 did not react with most antisera against other rickettsial species or control antigens (specificity = 92%, n = 13) using a positive cutoff value determined with eight uninfected rabbit sera. Refolded r56 was evaluated further by ELISA, using 128 sera obtained from patients with suspected scrub typhus from Korat, Thailand, and 74 serum specimens from healthy Thai soldiers. By using the indirect immunoperoxidase assay as the reference assay, the recombinant antigen exhibited a sensitivity and specificity of 93% or greater for detection of both IgG and IgM in the ELISA at 1:400 serum dilution. These results strongly suggest that purified r56 is a suitable candidate for replacing the density gradient-purified, rickettsia-derived, whole-cell antigen currently used in the commercial dipstick assay available in the United States. PMID:9665960
Ching, W M; Wang, H; Eamsila, C; Kelly, D J; Dasch, G A
1998-07-01
The variable 56-kDa major outer membrane protein of Orientia tsutsugamushi is the immunodominant antigen in human scrub typhus infections. The gene encoding this protein from Karp strain was cloned into the expression vector pET11a. The recombinant protein (r56) was expressed as a truncated nonfusion protein (amino acids 80 to 456 of the open reading frame) which formed an inclusion body when expressed in Escherichia coli BL21. Refolded r56 was purified and compared to purified whole-cell lysate of the Karp strain of O. tsutsugamushi by immunoglobulin G (IgG) enzyme-linked immunosorbent assay (ELISA) for reactivity with rabbit sera prepared against eight antigenic prototypes of O. tsutsugamushi as well as several other species of Rickettsiales and nonrickettsial antigens. Refolded r56 exhibited broad reactivity with the rabbit antisera against the Orientia prototypes, and the ELISA reactions with the r56 and Karp whole-cell lysate antigens correlated well (r = 0.81, n = 22, sensitivity compared to that of standard ELISA of 91%). Refolded r56 did not react with most antisera against other rickettsial species or control antigens (specificity = 92%, n = 13) using a positive cutoff value determined with eight uninfected rabbit sera. Refolded r56 was evaluated further by ELISA, using 128 sera obtained from patients with suspected scrub typhus from Korat, Thailand, and 74 serum specimens from healthy Thai soldiers. By using the indirect immunoperoxidase assay as the reference assay, the recombinant antigen exhibited a sensitivity and specificity of 93% or greater for detection of both IgG and IgM in the ELISA at 1:400 serum dilution. These results strongly suggest that purified r56 is a suitable candidate for replacing the density gradient-purified, rickettsia-derived, whole-cell antigen currently used in the commercial dipstick assay available in the United States.
Outbreak of scrub typhus in Puducherry & Tamil Nadu during cooler months
Stephen, Selvaraj; Sangeetha, Balakrishnan; Ambroise, Stanley; Sarangapani, Kengamuthu; Gunasekaran, Dhandapany; Hanifah, Mohamed; Somasundaram, Subramanian
2015-01-01
Background & objectives: The southern part of India has witnessed an increase in scrub typhus (ST) during the past ten years. ST outbreaks occurred during winter months but at intervals of one to three years. With only a few reports of ST in Puducherry, this study was undertaken to look for the persistence of ST cases in Puducherry and Tamil Nadu in the winter months. Methods: During relatively cooler months of September, 2012 to March, 2013, a total of 45 patients with fever and clinical suspicion of ST and who provided both acute and convalescent blood samples were included. Total WBC, platelet counts, serum creatinine, liver enzymes levels and a rapid immunochromatographic test (RICT) for ST were first done. Paired serum samples were analysed by two specific tests - ST IgM and IgG ELISA- and a non-specific, but widely used Weil-Felix (WF) test. Results: Of the 45 patients, 21 adults and seven children were confirmed as ST based on clinical and laboratory findings, and positivity in specific serological test(s). Setting ST IgM and IgG ELISA as reference, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for RICT were 91.67, 85.71 per cent; 90.48, 100 per cent; 91.67, 100 per cent and 90.48, 80.95 per cent, respectively. Similarly, for WF the values were 83.33, 75 per cent; 95.24, 100 per cent; 95.24, 100 per cent and 83.33, 70.83 per cent, respectively. Interpretation & conclusions: ST continues to persist in the cooler months in Puducherry and neighbouring Tamil Nadu with fever and myalgia as prominent features. None of the tests evaluated in this study was found to be ideal, but ST IgM/IgG ELISA was useful for batch testing and the non-specific WF test can be used in resource poor settings. PMID:26658595
Dasch, Gregory A.
2018-01-01
Orientia tsutsugamushi (Ots) is an obligate, intracellular, mite-transmitted human pathogen which causes scrub typhus. Understanding the diversity of Ots antigens is essential for designing specific diagnostic assays and efficient vaccines. The protective immunodominant type-specific 56 kDa antigen (TSA) of Ots varies locally and across its geographic distribution. TSA contains four hypervariable domains. We bioinformatically analyzed 345 partial sequences of TSA available from India, most of which contain only the three variable domains (VDI-III) and three spacer conserved domains (SVDI, SVDII/III, SVDIII). The total number (152) of antigenic types (amino acid variants) varied from 14–36 in the six domains of TSA that we studied. Notably, 55% (787/1435) of the predicted CD4 T-cell epitopes (TCEs) from all the six domains had high binding affinities (HBA) to at least one of the prevalent Indian human leukocyte antigen (HLA) alleles. A surprisingly high proportion (61%) of such TCEs were from spacer domains; indeed 100% of the CD4 TCEs in the SVDI were HBA. TSA sequences from India had more antigenic types (AT) than TSA from Korea. Overall, >90% of predicted CD4 TCEs from spacer domains were predicted to have HBA against one or more prevalent HLA types from Indian, Korean, Asia-Pacific region or global population data sets, while only <50% of CD4 TCEs in variable domains exhibited such HBA. The phylogenetically and immunologically important amino acids in the conserved spacer domains were identified. Our results suggest that the conserved spacer domains are predicted to be functionally more important than previously appreciated in immune responses to Ots infections. Changes occurring at the TCE level of TSA may contribute to the wide range of pathogenicity of Ots in humans and mouse models. CD4 T-cell functional experiments are needed to assess the immunological significance of these HBA spacer domains and their role in clearance of Ots from Indian patients. PMID:29698425
Kumlert, Rawadee; Chaisiri, Kittipong; Anantatat, Tippawan; Stekolnikov, Alexandr A; Morand, Serge; Prasartvit, Anchana; Makepeace, Benjamin L; Sungvornyothin, Sungsit; Paris, Daniel H
2018-01-01
Conventional gold standard characterization of chigger mites involves chemical preparation procedures (i.e. specimen clearing) for visualization of morphological features, which however contributes to destruction of the arthropod host DNA and any endosymbiont or pathogen DNA harbored within the specimen. In this study, a novel work flow based on autofluorescence microscopy was developed to enable identification of trombiculid mites to the species level on the basis of morphological traits without any special preparation, while preserving the mite DNA for subsequent genotyping. A panel of 16 specifically selected fluorescence microscopy images of mite features from available identification keys served for complete chigger morphological identification to the species level, and was paired with corresponding genotype data. We evaluated and validated this method for paired chigger morphological and genotypic ID using the mitochondrial cytochrome c oxidase subunit I gene (coi) in 113 chigger specimens representing 12 species and 7 genera (Leptotrombidium, Ascoschoengastia, Gahrliepia, Walchia, Blankaartia, Schoengastia and Schoutedenichia) from the Lao People's Democratic Republic (Lao PDR) to the species level (complete characterization), and 153 chiggers from 5 genera (Leptotrombidium, Ascoschoengastia, Helenicula, Schoengastiella and Walchia) from Thailand, Cambodia and Lao PDR to the genus level. A phylogenetic tree constructed from 77 coi gene sequences (approximately 640 bp length, n = 52 new coi sequences and n = 25 downloaded from GenBank), demonstrated clear grouping of assigned morphotypes at the genus levels, although evidence of both genetic polymorphism and morphological plasticity was found. With this new methodology, we provided the largest collection of characterized coi gene sequences for trombiculid mites to date, and almost doubled the number of available characterized coi gene sequences with a single study. The ability to provide paired phenotypic-genotypic data is of central importance for future characterization of mites and dissecting the molecular epidemiology of mites transmitting diseases like scrub typhus.
Chaisiri, Kittipong; Anantatat, Tippawan; Stekolnikov, Alexandr A.; Morand, Serge; Prasartvit, Anchana; Makepeace, Benjamin L.; Sungvornyothin, Sungsit; Paris, Daniel H.
2018-01-01
Background Conventional gold standard characterization of chigger mites involves chemical preparation procedures (i.e. specimen clearing) for visualization of morphological features, which however contributes to destruction of the arthropod host DNA and any endosymbiont or pathogen DNA harbored within the specimen. Methodology/Principal findings In this study, a novel work flow based on autofluorescence microscopy was developed to enable identification of trombiculid mites to the species level on the basis of morphological traits without any special preparation, while preserving the mite DNA for subsequent genotyping. A panel of 16 specifically selected fluorescence microscopy images of mite features from available identification keys served for complete chigger morphological identification to the species level, and was paired with corresponding genotype data. We evaluated and validated this method for paired chigger morphological and genotypic ID using the mitochondrial cytochrome c oxidase subunit I gene (coi) in 113 chigger specimens representing 12 species and 7 genera (Leptotrombidium, Ascoschoengastia, Gahrliepia, Walchia, Blankaartia, Schoengastia and Schoutedenichia) from the Lao People’s Democratic Republic (Lao PDR) to the species level (complete characterization), and 153 chiggers from 5 genera (Leptotrombidium, Ascoschoengastia, Helenicula, Schoengastiella and Walchia) from Thailand, Cambodia and Lao PDR to the genus level. A phylogenetic tree constructed from 77 coi gene sequences (approximately 640 bp length, n = 52 new coi sequences and n = 25 downloaded from GenBank), demonstrated clear grouping of assigned morphotypes at the genus levels, although evidence of both genetic polymorphism and morphological plasticity was found. Conclusions/Significance With this new methodology, we provided the largest collection of characterized coi gene sequences for trombiculid mites to date, and almost doubled the number of available characterized coi gene sequences with a single study. The ability to provide paired phenotypic-genotypic data is of central importance for future characterization of mites and dissecting the molecular epidemiology of mites transmitting diseases like scrub typhus. PMID:29494599
Abundances and host relationships of chigger mites in Yunnan Province, China.
Zhan, Y-Z; Guo, X-G; Speakman, J R; Zuo, X-H; Wu, D; Wang, Q-H; Yang, Z-H
2013-06-01
This paper reports on ectoparasitic chigger mites found on small mammals in Yunnan Province, southwest China. Data were accumulated from 19 investigation sites (counties) between 2001 and 2009. A total of 10 222 small mammal hosts were captured and identified; these represented 62 species, 34 genera and 11 families in five orders. From the body surfaces of these 10 222 hosts, a total of 92 990 chigger mites were collected and identified microscopically. These represented 224 species, 22 genera and three subfamilies in the family Trombiculidae (Trombidiformes). Small mammals were commonly found to be infested by chigger mites and most host species harboured several species of mite. The species diversity of chigger mites in Yunnan was much higher than diversities reported previously in other provinces of China and in other countries. A single species of rodent, Eothenomys miletus (Rodentia: Cricetidae), carried 111 species of chigger mite, thus demonstrating the highest species diversity and heaviest mite infestation of all recorded hosts. This diversity is exceptional compared with that of other ectoparasites. Of the total 224 mite species, 21 species accounted for 82.2% of all mites counted. Two species acting as major vectors for scrub typhus (tsutsugamushi disease), Leptotrombidium scutellare and Leptotrombidium deliense, were identified as the dominant mite species in this sample. In addition to these two major vectors, 12 potential or suspected vector species were found. Most species of chigger mite had a wide range of hosts and low host specificity. For example, L. scutellare parasitized 30 species of host. The low host specificity of chigger mites may increase their probability of encountering humans, as well as their transmission of scrub typhus among different hosts. Hierarchical clustering analysis showed that similarities between different chigger mite communities on the 18 main species of small mammal host did not accord with the taxonomic affinity of the hosts. This suggests that the distribution of chigger mites may be strongly influenced by the environment in which hosts live. © 2012 The Royal Entomological Society.
Predictive diagnostic value of the tourniquet test for the diagnosis of dengue infection in adults
Mayxay, Mayfong; Phetsouvanh, Rattanaphone; Moore, Catrin E; Chansamouth, Vilada; Vongsouvath, Manivanh; Sisouphone, Syho; Vongphachanh, Pankham; Thaojaikong, Thaksinaporn; Thongpaseuth, Soulignasack; Phongmany, Simmaly; Keolouangkhot, Valy; Strobel, Michel; Newton, Paul N
2011-01-01
Objective To examine the accuracy of the admission tourniquet test in the diagnosis of dengue infection among Lao adults. Methods Prospective assessment of the predictive diagnostic value of the tourniquet test for the diagnosis of dengue infection, as defined by IgM, IgG and NS1 ELISAs (Panbio Ltd, Australia), among Lao adult inpatients with clinically suspected dengue infection. Results Of 234 patients with clinically suspected dengue infection on admission, 73% were serologically confirmed to have dengue, while 64 patients with negative dengue serology were diagnosed as having scrub typhus (39%), murine typhus (11%), undetermined typhus (12%), Japanese encephalitis virus (5%), undetermined flavivirus (5%) and typhoid fever (3%); 25% had no identifiable aetiology. The tourniquet test was positive in 29.1% (95% CI = 23.2–34.9%) of all patients and in 34.1% (95% CI = 27.0–41.2%) of dengue-seropositive patients, in 32.7% (95% CI = 23.5–41.8) of those with dengue fever and in 36.4% (95% CI = 24.7–48.0) of those with dengue haemorrhagic fever. Interobserver agreement for the tourniquet test was 90.2% (95% CI = 86.4–94.0) (Kappa = 0.76). Using ELISAs as the diagnostic gold standard, the sensitivity of the tourniquet test was 33.5–34%; its specificity was 84–91%. The positive and negative predictive values were 85–90% and 32.5–34%, respectively. Conclusions The admission tourniquet test has low sensitivity and adds relatively little value to the diagnosis of dengue among Lao adult inpatients with suspected dengue. Although a positive tourniquet test suggests dengue and that treatment of alternative diagnoses may not be needed, a negative test result does not exclude dengue. PMID:20958892
Chikeka, Ijeuru; Dumler, J. Stephen
2015-01-01
Bacterial zoonoses comprise a group of diseases in humans or animals acquired by direct contact with or by oral consumption of contaminated animal materials, or via arthropod vectors. Among neglected infections, bacterial zoonoses are among the most neglected given emerging data on incidence and prevalence as causes of acute febrile illness, even in areas where recognized neglected tropical diseases occur frequently. While many other bacterial infections could also be considered in this neglected category, five distinct infections stand out because they are globally distributed, are acute febrile diseases, have high rates of morbidity and case fatality, and are reported as commonly as malaria, typhoid or dengue virus infections in carefully designed studies in which a broad spectrum diagnoses are actively sought. Thus, this review will focus attention on leptospirosis, relapsing fever borreliosis, and rickettsioses, including scrub typhus, murine typhus and spotted fever group rickettsiosis. Of greatest interest is the lack of distinguishing clinical features among these infections when in humans, which confounds diagnosis where laboratory confirmation is lacking, and in regions where clinical diagnosis is often attributed to one of several perceived more common threats. As diseases such as malaria come under improved control, the real impact of these common and under-recognized infections will become evident, as will the requirement for the strategies and allocation of resources for their control. PMID:25964152
Etiology of Acute, Non-Malaria, Febrile Illnesses in Jayapura, Northeastern Papua, Indonesia
Punjabi, Narain H.; Taylor, Walter R. J.; Murphy, Gerald S.; Purwaningsih, Sri; Picarima, Helena; Sisson, John; Olson, James G.; Baso, Samuel; Wangsasaputra, Ferry; Lesmana, Murad; Oyofo, Buhari A.; Simanjuntak, Cyrus H.; Subekti, Decy; Corwin, Andrew L.; Richie, Thomas L.
2012-01-01
We conducted a prospective, inpatient fever study in malaria-endemic Papua, Indonesia to determine non-malaria fever etiologies. Investigations included malaria blood films, blood culture, paired serologic samples analysis for dengue, Japanese encephalitis, leptospirosis, scrub typhus, murine typhus, and spotted fever group rickettsia. During 1997–2000, 226 patients (127 males and 99 females) 1–80 years of age (median age = 25 years) were enrolled. Positive blood cultures (n = 34, 15%) were obtained for Salmonella Typhi (n = 13), Escherichia coli (n = 8), Streptococcus pneumoniae (n = 6), Staphylococcus aureus (n = 5), Streptococcus pyogenes (n = 1), and Klebsiella pneumoniae (n = 1). Twenty (8.8%) patients were positive for leptospirosis by polymerase chain reaction. Eighty (35.4%) of 226 patients had ≥ 1 positive serology, diagnostic for 15 rickettsial and 9 dengue cases. Acid-fast bacilli–positive sputum was obtained from three patients. Most common confirmed (81 of 226, 35.8%)/suspected diagnoses were typhoid fever (n = 41), pneumonia (n = 29), leptospirosis (n = 28), urinary tract infections (n = 20), rickettsioses (n = 19), dengue (n = 17), and meningitis/encephalitis (n = 15). There were 17 deaths, 7 (46.7%) were caused by meningitis/encephalitis. Multiple positive serologic results and few confirmed diagnoses indicate the need for improved diagnostics. PMID:22232450
Malaria-Associated Mortality in the Australian Defence Force during the Twentieth Century.
Shanks, G Dennis
2017-08-01
Malaria has been a military problem throughout history capable of causing epidemics that stop military operations. Individual mortality was examined from records of the three major wars of the 20th century that involved Australia in which 133 (1914-1919), 92 (1943-1945), and two (1965-1967) soldiers are known to have died with malaria. Those dying were predominately enlisted soldiers with a mean age of 29 years often complicated by other infections such as influenza, pneumonia or scrub typhus. Lethal epidemics of falciparum malaria occurred in Palestine/Syria in October 1918 and New Guinea in September 1943 to March 1944. Although no Australian soldier has died in nearly 50 years from malaria, there were three serious falciparum infections in soldiers in East Timor 1999-2000 who might have died if intensive care had not been provided. Recent military deployments into Africa including United Nations contingents still show falciparum malaria's lethality despite the availability of effective malaria chemoprophylaxis.
Kitchen, Lynn W; Vaughn, David W
2007-10-10
U.S. military physicians and researchers have collaborated in the development of eight U.S.-licensed vaccines since 1934, when product efficacy requirements were added to product safety requirements mandated in 1902. These vaccines include influenza (1945), rubella (1969), adenovirus types 4 and 7 (1980), meningococcus A, C, Y, W-135 (1981), hepatitis B (1981), oral typhoid (1989), Japanese encephalitis (1992), and hepatitis A (1995). Current efforts include new adenovirus and Japanese encephalitis vaccines, and vaccines to prevent dengue, diarrhea due to enterotoxigenic E. coli, Campylobacter, and Shigella, malaria, hemorrhagic fever with renal syndrome, scrub typhus, meningococcus type B, and HIV infection. All vaccines currently administered to U.S. military forces must be licensed by the U.S. Food and Drug Administration (FDA).
Chikeka, I; Dumler, J S
2015-05-01
Bacterial zoonoses comprise a group of diseases in humans or animals acquired by direct contact with or by oral consumption of contaminated animal materials, or via arthropod vectors. Among neglected infections, bacterial zoonoses are among the most neglected given emerging data on incidence and prevalence as causes of acute febrile illness, even in areas where recognized neglected tropical diseases occur frequently. Although many other bacterial infections could also be considered in this neglected category, five distinct infections stand out because they are globally distributed, are acute febrile diseases, have high rates of morbidity and case fatality, and are reported as commonly as malaria, typhoid or dengue virus infections in carefully designed studies in which broad-spectrum diagnoses are actively sought. This review will focus attention on leptospirosis, relapsing fever borreliosis and rickettsioses, including scrub typhus, murine typhus and spotted fever group rickettsiosis. Of greatest interest is the lack of distinguishing clinical features among these infections when in humans, which confounds diagnosis where laboratory confirmation is lacking, and in regions where clinical diagnosis is often attributed to one of several perceived more common threats. As diseases such as malaria come under improved control, the real impact of these common and under-recognized infections will become evident, as will the requirement for the strategies and allocation of resources for their control. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Phasomkusolsil, Siriporn; Tanskul, Panita; Ratanatham, Supaporn; Watcharapichat, Pochaman; Phulsuksombati, Duangporn; Frances, Stephen P; Lerdthusnee, Kriangkrai; Linthicum, Kenneth J
2012-11-01
Leptotrombidium chiangraiensis Tanskul & Linthicum, and Leptotrombidium imphalum Vercammen-Grandjean are important vectors of scrub typhus in rice field habitats in northern Thailand. The developmental biology of all stages of the life cycle of two generations of these species of mites infected with Orientia tsutsugamushi (Hayashi) and uninfected mites is reported. The development of the infected lines of both F1 and F2 L. chiangraiensis were significantly longer than their respective uninfected lines (P < 0.05). The developmental times of uninfected and infected F1 lines of L. imphalum were not significantly different; however, F2 infected lines took significantly longer to develop (P < 0.05). Both F1 and F2 generations of infected L. imphalum and L. chiangraiensis oviposited on average >150 fewer eggs than uninfected mites.
Widespread Rickettsia spp. Infections in Ticks (Acari: Ixodoidea) in Taiwan.
Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Lee, Pei-Lung; Wu, Yin-Wen; Chung, Chien-Kung; Wang, Hsi-Chieh
2015-09-01
Ticks are second to mosquitoes as the most important disease vectors, and recent decades have witnessed the emergence of many novel tick-borne rickettsial diseases, but systematic surveys of ticks and tick-borne rickettsioses are generally lacking in Asia. We collected and identified ticks from small mammal hosts between 2006 and 2010 in different parts of Taiwan. Rickettsia spp. infections in ticks were identified by targeting ompB and gltA genes with nested polymerase chain reaction. In total, 2,732 ticks were collected from 1,356 small mammals. Rhipicephalus haemaphysaloides Supino (51.8% of total ticks), Haemaphysalis bandicota Hoogstraal & Kohls (28.0%), and Ixodes granulatus Supino (20.0%) were the most common tick species, and Rattus losea Swinhoe (44.7% of total ticks) and Bandicota indica Bechstein (39.9%) were the primary hosts. The average Rickettsia infective rate in 329 assayed ticks was 31.9% and eight Rickettsia spp. or closely related species were identified. This study shows that rickettsiae-infected ticks are widespread in Taiwan, with a high diversity of Rickettsia spp. circulating in the ticks. Because notifiable rickettsial diseases in Taiwan only include mite-borne scrub typhus and flea-borne murine typhus, more studies are warranted for a better understanding of the real extent of human risks to rickettsioses in Taiwan. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Satoh, Masaaki; Akashi, Shintaro; Ogawa, Motohiko; Wakeyama, Takatoshi; Ogawa, Hiroshi; Fukuma, Aiko; Taniguchi, Satoshi; Tani, Hideki; Kurosu, Takeshi; Fukushi, Shuetsu; Shimojima, Masayuki; Ando, Shuji; Saijo, Masayuki
2017-01-01
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease caused by the SFTS virus (SFTSV). The aim of this study was to clarify whether SFTS is potentially mis-diagnosed as rickettsioses, including spotted fever, typhus fever, and scrub typhus, which are also tick-borne disease. A total of 464 serum samples collected from 222 patients with clinically suspected rickettsiosis between 1999 and 2012 were tested for antibodies against the SFTSV. Of the 464 serum samples, one was positive for antibodies against the virus in an enzyme-linked immunosorbent assay and indirect immunofluorescence assay. The patient of SFTSV antibody-positive sample (15 days after disease onset) was positive for SFTSV genome in the acute phase sample (3 days after disease onset) as determined via reverse transcription-quantitative polymerase chain reaction. This patient, who was a resident of the Yamaguchi prefecture in Western Japan, was in his 40s when he showed symptoms in 2011. As the result, 1 of 222 patients, who was clinically suspected of rickettsiosis, was retrospectively diagnosed with SFTS. In this case, both the C-reactive protein and white blood cell count levels were lower than the ranges of these parameters for patients diagnosed with rickettsiosis. Therefore, SFTS should be considered in the differential diagnosis for rickettsiosis in Japan. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Dittrich, Sabine; Sunyakumthorn, Piyanate; Rattanavong, Sayaphet; Phetsouvanh, Rattanaphone; Panyanivong, Phonepasith; Sengduangphachanh, Amphonsavanh; Phouminh, Phonelavanh; Anantatat, Tippawan; Chanthongthip, Anisone; Lee, Sue J; Dubot-Pérès, Audrey; Day, Nicholas P J; Paris, Daniel H; Newton, Paul N; Turner, Gareth D H
2015-08-01
Blood-brain barrier (BBB) function and cerebrospinal fluid (CSF) biomarkers were measured in patients admitted to hospital with severe neurological infections in the Lao People's Democratic Republic (N = 66), including bacterial meningitis (BM; N = 9) or tuberculosis meningitis (TBM; N = 11), Japanese encephalitis virus (JEV; N = 25), and rickettsial infections (N = 21) including murine and scrub typhus patients. The albumin index (AI) and glial fibrillary acidic protein (GFAP) levels were significantly higher in BM and TBM than other diseases but were also raised in individual rickettsial patients. Total tau protein was significantly raised in the CSF of JEV patients. No differences were found between clinical or neurological symptoms, AI, or biomarker levels that allowed distinction between severe neurological involvement by Orientia tsutsugamushi compared with Rickettsia species. © The American Society of Tropical Medicine and Hygiene.
[Epidemic typhus in tropical Africa. A reemerging disease that is severe but curable].
Zoguéreh, D D; Ndihokubwayo, J B; Simboyinuma, A
2000-01-01
In tropical regions of Africa, frequently subject to social and political upheavals, there is an ever-present threat of typhus epidemics, as shown by the recent typhus outbreak in Burundi in 1997. Epidemic typhus should be systematically suspected in certain epidemiological conditions: famine, war, high-density populations (refugee camps, prisons), the presence of body louse in the clothing, and in the presence of certain clinical findings: severe infectious syndrome (temperature above 38 C), severe pain and muscle weakness, with coughing and severe neurological signs. The rapid diagnosis and treatment of typhus are essential. The prognosis has improved, thanks to the specific antibiotics that are currently available, particularly doxycycline, prescribed as a single oral dose of 200 mg for adults or of 100 mg for children. However, the prognosis still depends to a large extent on the speed of diagnosis. Typhus epidemics could be effectively predicted and limited if the measures for control of the body louse recommended by the World Health Organization were applied in the areas with the most favorable epidemiological conditions.
Chen, Zhi-Hai; Qin, Xin-Cheng; Song, Rui; Shen, Yi; Chen, Xiao-Ping; Wang, Wen; Zhao, Yong-Xiang; Zhang, Jing-Shan; He, Jin-Rong; Li, Ming-Hui; Zhao, Xue-Hua; Liu, De-Wei; Fu, Xiao-Kang; Tian, Di; Li, Xing-Wang; Xu, Jianguo; Plyusnin, Alexander; Holmes, Edward C; Zhang, Yong-Zhen
2014-01-01
Hemorrhagic fevers (HF) caused by viruses and bacteria are a major public health problem in China and characterized by variable clinical manifestations, such that it is often difficult to achieve accurate diagnosis and treatment. The causes of HF in 85 patients admitted to Dandong hospital, China, between 2011-2012 were determined by serological and PCR tests. Of these, 34 patients were diagnosed with Huaiyangshan hemorrhagic fever (HYSHF), 34 with Hemorrhagic Fever with Renal Syndrome (HFRS), one with murine typhus, and one with scrub typhus. Etiologic agents could not be determined in the 15 remaining patients. Phylogenetic analyses of recovered bacterial and viral sequences revealed that the causative infectious agents were closely related to those described in other geographical regions. As these diseases have no distinctive clinical features in their early stage, only 13 patients were initially accurately diagnosed. The distinctive clinical features of HFRS and HYSHF developed during disease progression. Enlarged lymph nodes, cough, sputum, and diarrhea were more common in HYSHF patients, while more HFRS cases presented with headache, sore throat, oliguria, percussion pain kidney area, and petechiae. Additionally, HYSHF patients displayed significantly lower levels of white blood cells (WBC), higher levels of creations kinase (CK) and alanine aminotransferase (ALT), while HFRS patients presented with an elevation of blood urea nitrogen (BUN) and creatinine (CREA). These clinical features will assist in the accurate diagnosis of both HYSHF and HFRS. Overall, our data reveal the complexity of pathogens causing HFs in a single Chinese hospital, and highlight the need for accurate early diagnosis and a better understanding of their distinctive clinical features.
Raĭkova, S V; Zav'ialov, A I
2013-07-01
The article is concerned to the materials about epidemiologic situation of typhus fever in the regions around Volga river (Saratovsky, Samarsky and others) during World War I (1914-1918) among the military personnel of the Russian army and among the civilians. The main reasons for spread of infection, ways of the transmission, and also measures for decreasing of level of morbidity on the different stages of evacuation of patients with typhus fever in the safer hospitals are shown. The most important methods of fighting against epidemic of typhus fever were: isolation of patients in separate special hospitals, desincection and disinfection measures in the foci of infection and organization appropriate sanitary conditions for military man in the army and among civilians. Acquired valuable experience of territorial and military doctors during the period of epidemic of typhus fever allowed receiving complex effective antiepidemic measures of fighting and prevention from this disease.
Eradication of typhus exanthematicus in Bosnia and Herzegovina.
Puvacić, Zlatko; Beslagić, Edina; Zvizdić, Sukrija; Puvacić, Sandra; Ravlija, Jelena; Hamzić, Sadeta
2006-02-01
Typhus exanthematicus in Bosnia and Herzegovina held in endemic areas from which especially quickly began spread after 1945. That year, in 1945, one hundred epidemics of typhus fever appeared, with the highest incidence rate in Europe of 215.04 per 1,000. Directions of unique program in the world were to eradicate lice of the body, but also establish monitoring of the recidivism, Brill-Zinsser disease. Since 1971, typhus exanthematicus (classical typhus) hasn't appeared in Bosnia and Herzegovina, so epidemic typhus can considered as an eradicated communicable disease.
Acute kidney injury due to tropical infectious diseases and animal venoms: a tale of 2 continents.
Burdmann, Emmanuel A; Jha, Vivekanand
2017-05-01
South and Southeast Asia and Latin American together comprise 46 countries and are home to approximately 40% of the world population. The sociopolitical and economic heterogeneity, tropical climate, and malady transitions characteristic of the region strongly influence disease behavior and health care delivery. Acute kidney injury epidemiology mirrors these inequalities. In addition to hospital-acquired acute kidney injury in tertiary care centers, these countries face a large preventable burden of community-acquired acute kidney injury secondary to tropical infectious diseases or animal venoms, affecting previously healthy young individuals. This article reviews the epidemiology, clinical picture, prevention, risk factors, and pathophysiology of acute kidney injury associated with tropical diseases (malaria, dengue, leptospirosis, scrub typhus, and yellow fever) and animal venom (snakes, bees, caterpillars, spiders, and scorpions) in tropical regions of Asia and Latin America, and discusses the potential future challenges due to emerging issues. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.
Lerdthusnee, Kriangkrai; Khlaimanee, Nittaya; Monkanna, Taweesak; Sangjun, Noppadon; Mungviriya, Siriporn; Linthicum, Kenneth J; Frances, Stephen P; Kollars, Thomas M; Coleman, Russell E
2002-05-01
Thirteen different laboratory colonies of Leptotrombidim chiggers [L. chiangraiensis Tanskul & Linthicum, L. deliense Walch and L. imphalum (Vercammen-Grandjean &Langston)] were evaluated for their ability to transmit Orientia tsutsugamushi (Hyashi) to mice. Of 4,372 transmission attempts using individual chiggers from all 13 colonies, 75% (n = 3,275) successfully infected mice. Transmission rates for the individual chigger colonies ranged from 7 to 80%. Increasing the number of chiggers that fed on a given mouse generally increased transmission rates. Transmission of O. tsutsugamushi to mice by different generations (F1-F11) of certain chigger colonies was stable; however, transmission rates varied greatly in other colonies. Transmission rates (both vertical and horizontal) of several L. changraiensis colonies and the L. deliense colony were the highest, suggesting that these colonies may be useful for the development of a chigger-challenge model that can be used to evaluate the efficacy of candidate scrub typhus vaccines or therapeutic agents in laboratory mice.
Mites (family Trombiculidae) parasitizing birds migrating from Africa to Europe
Varma, M. G. R.
1964-01-01
The mechanisms of dissemination of arthropod-borne human and animal pathogens are of considerable interest to the epidemiologist, veterinarian and biologist. Birds which are hosts to such pathogens and their arthropod vectors could transport them over long distances during their spring and autumn migratory flights. In April 1961, birds migrating from Africa to Europe were collected in south-western Spain and examined for ectoparasites and antibodies to arboviruses. Fully engorged larvae of two species of trombiculid mites unknown in Europe (genera Neoschoengastia and Blankaartia) but found in Africa were collected from two of the migrating birds (redstart and little bittern), suggesting that the birds were carrying the mites from Africa to Europe. Trombiculid mites are the proven vectors of scrub typhus; they have also been implicated in the transmission of human haemorrhagic nephroso-nephritis. The finding of the mite larvae on migrating birds is therefore of some epidemiological interest and underlines the importance of obtaining more data on the dispersal of trombiculids by migrating birds. PMID:14267750
Paris, Daniel H; Blacksell, Stuart D; Newton, Paul N; Day, Nicholas P J
2008-12-01
We present a loop-mediated isothermal PCR assay (LAMP) targeting the groEL gene, which encodes the 60kDa heat shock protein of Orientia tsutsugamushi. Evaluation included testing of 63 samples of contemporary in vitro isolates, buffy coats and whole blood samples from patients with fever. Detection limits for LAMP were assessed by serial dilutions and quantitation by real-time PCR assay based on the same target gene: three copies/microl for linearized plasmids, 26 copies/microl for VERO cell culture isolates, 14 copies/microl for full blood samples and 41 copies/microl for clinical buffy coats. Based on a limited sample number, the LAMP assay is comparable in sensitivity with conventional nested PCR (56kDa gene), with limits of detection well below the range of known admission bacterial loads of patients with scrub typhus. This inexpensive method requires no sophisticated equipment or sample preparation, and may prove useful as a diagnostic assay in financially poor settings; however, it requires further prospective validation in the field setting.
Redhead, John; Cuevas-Gonzales, Maria; Smith, Geoffrey; Gerard, France; Pywell, Richard
2012-04-30
Controlling scrub encroachment is a major challenge for conservation management on chalk grasslands. However, direct comparisons of scrub removal methods have seldom been investigated, particularly at the landscape scale. Effective monitoring of grassland scrub is problematic as it requires simultaneous information on large scale patterns in scrub cover and fine-scale changes in the grassland community. This study addressed this by combining analysis of aerial imagery with rapid field surveys in order to compare the effectiveness of four scrub management strategies on Defence Training Estate Salisbury Plain, UK. Study plots were sited within areas undergoing management and in unmanaged controls. Controls showed dramatic increases in scrub cover, with encroachment of a mean 1096 m(2) per hectare over ten years. Whilst all management strategies were effective in reducing scrub encroachment, they differed in their ability to influence regeneration of scrub and grassland quality. There was a general trend, evident in both the floral community and scrub levels, of increased effectiveness with increasing management intensity. The dual methodology proved highly effective, allowing rapid collection of data over a range of variables and spatial scales unavailable to each method individually. The methodology thus demonstrates potential for a useful monitoring tool. Copyright © 2011 Elsevier Ltd. All rights reserved.
An Overview of Epidemic Typhus in the World and Iran during the 19th and 20th Centuries.
Azizi, Mohammad Hossein; Bahadori, Moslem; Azizi, Farzaneh
2016-10-01
The present article provides a concise historical review on classical epidemic typhus (exanthemata typhus) in the world as well its outbreaks in Iran mainly during the 19th and 20th centuries. Typhus is still a potential public health threat under certain conditions, despite the fact that nowadays, efficient antibiotics are accessible and sanitary conditions which lead to typhus outbreaks have improved significantly.
IAP Guidelines on Rickettsial Diseases in Children.
Rathi, Narendra; Kulkarni, Atul; Yewale, Vijay
2017-03-15
To formulate practice guidelines on rickettsial diseases in children for pediatricians across India. Rickettsial diseases are increasingly being reported from various parts of India. Due to low index of suspicion, nonspecific clinical features in early course of disease, and absence of easily available, sensitive and specific diagnostic tests, these infections are difficult to diagnose. With timely diagnosis, therapy is easy, affordable and often successful. On the other hand, in endemic areas, where healthcare workers have high index of suspicion for these infections, there is rampant and irrational use of doxycycline as a therapeutic trial in patients of undifferentiated fevers. Thus, there is a need to formulate practice guidelines regarding rickettsial diseases in children in Indian context. A committee was formed for preparing guidelines on rickettsial diseases in children in June 2016. A meeting of consultative committee was held in IAP office, Mumbai and scientific content was discussed. Methodology and results were scrutinized by all members and consensus was reached. Textbook references and published guidelines were also used in few instances to make recommendations. Various Indian and international publications pertinent to present study were collated and guidelines were approved by all committee members. Future updates in these guidelines will be dictated by new scientific data in the field of rickettsial diseases in children. Indian tick typhus and scrub typhus are commonly seen rickettsial diseases in India. It is recommended that practicing pediatricians should be well conversant with compatible clinical scenario, suggestive epidemiological features, differential diagnoses and suggestive laboratory features to make diagnosis and avoid over diagnosis of these infections, as suggested in these guidelines. Doxycycline is the drug of choice and treatment should begin promptly without waiting for confirmatory laboratory results.
Epidemic typhus meningitis in the southwestern United States.
Massung, R F; Davis, L E; Slater, K; McKechnie, D B; Puerzer, M
2001-03-15
A patient residing in New Mexico had murine typhus diagnosed. A novel molecular assay was performed at the Centers for Disease Control and Prevention, and Rickettsia prowazekii, the agent of epidemic typhus, was found, rather than R. typhi. To our knowledge, this is the first reported case of epidemic typhus confirmed by means of polymerase chain reaction--based testing of cerebrospinal fluid, and it introduces a novel assay for the molecular diagnosis of both epidemic and murine typhus.
Control of typhus fever in Finland during World War II.
Laurent, Helene
2009-12-01
The article describes the measures taken against the threat of typhus epidemic in Finland during the Second World War. Comparisons between countries at war and their different typhus prevention methods are made. The main method of typhus prevention in Finland consisted of regular sauna bathing, which was culturally acceptable and very efficient when combined with heating of the clothing. The Finnish troops remained virtually louse-free by ecological and traditional methods, and thus the spread of typhus fever in the army could be prevented.
La Scola, B; Rydkina, L; Ndihokubwayo, J B; Vene, S; Raoult, D
2000-07-01
Differentiation of murine typhus due to Rickettsia typhi and epidemic typhus due to Rickettsia prowazekii is critical epidemiologically but difficult serologically. Using serological, epidemiological, and clinical criteria, we selected sera from 264 patients with epidemic typhus and from 44 patients with murine typhus among the 29,188 tested sera in our bank. These sera cross-reacted extensively in indirect fluorescent antibody assays (IFAs) against R. typhi and R. prowazekii, as 42% of the sera from patients with epidemic typhus and 34% of the sera from patients with murine typhus exhibited immunoglobulin M (IgM) and/or IgG titers against the homologous antigen (R. prowazekii and R. typhi, respectively) that were more than one dilution higher than those against the heterologous antigen. Serum cross-adsorption studies and Western blotting were performed on sera from 12 selected patients, 5 with murine typhus, 5 with epidemic typhus, and 2 suffering from typhus of undetermined etiology. Differences in IFA titers against R. typhi and R. prowazekii allowed the identification of the etiological agent in 8 of 12 patients. Western blot studies enabled the identification of the etiological agent in six patients. When the results of IFA and Western blot studies were considered in combination, identification of the etiological agent was possible for 10 of 12 patients. Serum cross-adsorption studies enabled the differentiation of the etiological agent in all patients. Our study indicates that when used together, Western blotting and IFA are useful serological tools to differentiate between R. prowazekii and R. typhi exposures. While a cross-adsorption study is the definitive technique to differentiate between infections with these agents, it was necessary in only 2 of 12 cases (16.7%), and the high costs of such a study limit its use.
La Scola, Bernard; Rydkina, Lena; Ndihokubwayo, Jean-Bosco; Vene, Sirkka; Raoult, Didier
2000-01-01
Differentiation of murine typhus due to Rickettsia typhi and epidemic typhus due to Rickettsia prowazekii is critical epidemiologically but difficult serologically. Using serological, epidemiological, and clinical criteria, we selected sera from 264 patients with epidemic typhus and from 44 patients with murine typhus among the 29,188 tested sera in our bank. These sera cross-reacted extensively in indirect fluorescent antibody assays (IFAs) against R. typhi and R. prowazekii, as 42% of the sera from patients with epidemic typhus and 34% of the sera from patients with murine typhus exhibited immunoglobulin M (IgM) and/or IgG titers against the homologous antigen (R. prowazekii and R. typhi, respectively) that were more than one dilution higher than those against the heterologous antigen. Serum cross-adsorption studies and Western blotting were performed on sera from 12 selected patients, 5 with murine typhus, 5 with epidemic typhus, and 2 suffering from typhus of undetermined etiology. Differences in IFA titers against R. typhi and R. prowazekii allowed the identification of the etiological agent in 8 of 12 patients. Western blot studies enabled the identification of the etiological agent in six patients. When the results of IFA and Western blot studies were considered in combination, identification of the etiological agent was possible for 10 of 12 patients. Serum cross-adsorption studies enabled the differentiation of the etiological agent in all patients. Our study indicates that when used together, Western blotting and IFA are useful serological tools to differentiate between R. prowazekii and R. typhi exposures. While a cross-adsorption study is the definitive technique to differentiate between infections with these agents, it was necessary in only 2 of 12 cases (16.7%), and the high costs of such a study limit its use. PMID:10882661
Díaz, Fabián E; Abarca, Katia; Kalergis, Alexis M
2018-04-01
The obligate intracellular bacterium Orientia tsutsugamushi is the causative agent of scrub typhus in humans, a serious mite-borne disease present in a widespread area of endemicity, which affects an estimated 1 million people every year. This disease may exhibit a broad range of presentations, ranging from asymptomatic to fatal conditions, with the latter being due to disseminated endothelial infection and organ injury. Unique characteristics of the biology and host-pathogen interactions of O. tsutsugamushi , including the high antigenic diversity among strains and the highly variable, short-lived memory responses developed by the host, underlie difficulties faced in the pursuit of an effective vaccine, which is an imperative need. Other factors that have hindered scientific progress relative to the infectious mechanisms of and the immune response triggered by this bacterium in vertebrate hosts include the limited number of mechanistic studies performed on animal models and the lack of genetic tools currently available for this pathogen. However, recent advances in animal model development are promising to improve our understanding of host-pathogen interactions. Here, we comprehensively discuss the recent advances in and future perspectives on host-pathogen interactions and the modulation of immune responses related to this reemerging disease, highlighting the role of animal models. Copyright © 2018 American Society for Microbiology.
Effect of surgical hand scrub time on subsequent bacterial growth.
Wheelock, S M; Lookinland, S
1997-06-01
In this experimental study, the researchers evaluated the effect of surgical hand scrub time on subsequent bacterial growth and assessed the effectiveness of the glove juice technique in a clinical setting. In a randomized crossover design, 25 perioperative staff members scrubbed for two or three minutes in the first trial and vice versa in the second trial, after which the wore sterile surgical gloves for one hour under clinical conditions. The researchers then sampled the subjects' nondominant hands for bacterial growth, cultured aliquots from the sampling solution, and counted microorganisms. Scrubbing for three minutes produced lower mean log bacterial counts than scrubbing for two minutes. Although the mean bacterial count differed significantly (P = .02) between the two-minute and three-minute surgical hand scrub times, it fell below 0.5 log, which is the threshold for practical and clinical significance. This finding suggests that a two-minute surgical hand scrub is clinically as effective as a three-minute surgical had scrub. The glove juice technique demonstrated sensitivity and reliability in enumerating bacteria on the hands of perioperative staff members in a clinical setting.
Liu, Liang Qin; Mehigan, Sinead
2016-05-01
This systematic review aimed to critically appraise and synthesize updated evidence regarding the effect of surgical-scrub techniques on skin integrity and the incidence of surgical site infections. Databases searched include the Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Embase, and Cochrane Central. Our review was limited to eight peer-reviewed, randomized controlled trials and two nonrandomized controlled trials published in English from 1990 to 2015. Comparison models included traditional hand scrubbing with chlorhexidine gluconate or povidone-iodine against alcohol-based hand rubbing, scrubbing with a brush versus without a brush, and detergent-based antiseptics alone versus antiseptics incorporating alcohol solutions. Evidence showed that hand rubbing techniques are as effective as traditional scrubbing and seem to be better tolerated. Hand rubbing appears to cause less skin damage than traditional scrub protocols, and scrub personnel tolerated brushless techniques better than scrubbing using a brush. Copyright © 2016 AORN, Inc. Published by Elsevier Inc. All rights reserved.
Murine and epidemic typhus rickettsiae: how close is their relationship?
Woodward, T. E.
1982-01-01
Typhus fever has occurred globally as epidemic and endemic disorders. In 1910, Brill reported a typhus-like illness which Zinsser and others determined to be recurrent epidemic typhus fever. Maxcy, in 1926, proposed rodents and fleas as reservoir and vector, respectively, of endemic typhus, which Dyer confirmed in 1930. Animals experimentally infected with epidemic typhus (Rickettsia prowazeki) are immune to murine typhus (Rickettsia typhi) and vice versa. Similar solid cross-immunity exists for humans. The two diseases are clinically similar in pathologic and serologic reactions. Human epidemic typhus presumably involved a man-louse-man cycle without an animal reservoir. This concept is now questioned. Antibodies to R. prowazeki have been reported in livestock in Africa, rats in Manila, and from flying squirrels and humans in the United States. R. prowazeki was recovered from blood specimens of goats, sheep, from ixodid ticks, louse, and flea-ectoparasites of flying squirrels, and tissues of flying squirrels. More than 20 cases of squirrel-related acute epidemic typhus have been reported in the United States. R. prowazeki has not been recovered from human cases. Chemical studies of R. prowazeki and R. typhi show genetic similarities but differences in genome size and degree of hybridization suggest that interconversions between the two agents do not occur rapidly in nature. It is proposed that, with time, their relatedness will become even closer. PMID:6817526
The History of Epidemic Typhus.
Angelakis, Emmanouil; Bechah, Yassina; Raoult, Didier
2016-08-01
Epidemic typhus caused by Rickettsia prowazekii is one of the oldest pestilential diseases of humankind. The disease is transmitted to human beings by the body louse Pediculus humanus corporis and is still considered a major threat by public health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Epidemic typhus has accompanied disasters that impact humanity and has arguably determined the outcome of more wars than have soldiers and generals. The detection, identification, and characterization of microorganisms in ancient remains by paleomicrobiology has permitted the diagnosis of past epidemic typhus outbreaks through the detection of R. prowazekii. Various techniques, including microscopy and immunodetection, can be used in paleomicrobiology, but most of the data have been obtained by using PCR-based molecular techniques on dental pulp samples. Paleomicrobiology enabled the identification of the first outbreak of epidemic typhus in the 18th century in the context of a pan-European great war in the city of Douai, France, and supported the hypothesis that typhus was imported into Europe by Spanish soldiers returning from America. R. prowazekii was also detected in the remains of soldiers of Napoleon's Grand Army in Vilnius, Lithuania, which indicates that Napoleon's soldiers had epidemic typhus. The purpose of this article is to underscore the modern comprehension of clinical epidemic typhus, focus on the historical relationships of the disease, and examine the use of paleomicrobiology in the detection of past epidemic typhus outbreaks.
Weindling, P
1995-01-01
This paper provides an overview of the development of typhus vaccines between the first and second world wars. It is shown that there was a shift in the classification of the causal Rickettsiae from being classed as bacteria to being conceptualised as a type of virus. This 'paradigm switch' stimulated interest in the possibility of producing an effective medicine.
Lim, Tow Keang; Siow, Wen Ting
2018-01-01
Pneumonia in the tropics poses a heavy disease burden. The complex interplay of climate change, human migration influences and socio-economic factors lead to changing patterns of respiratory infections in tropical climate but also increasingly in temperate countries. Tropical and poorer countries, especially South East Asia, also bear the brunt of the global tuberculosis (TB) pandemic, accounting for almost one-third of the burden. But, as human migration patterns evolve, we expect to see more TB cases in higher income as well as temperate countries, and rise in infections like scrub typhus from ecotourism activities. Fuelled by the ease of air travel, novel zoonotic infections originating from the tropics have led to global respiratory pandemics. As such, clinicians worldwide should be aware of these new conditions as well as classical tropical bacterial pneumonias such as melioidosis. Rarer entities such as co-infections of leptospirosis and chikungunya or dengue will need careful consideration as well. In this review, we highlight aetiologies of pneumonia seen more commonly in the tropics compared with temperate regions, their disease burden, variable clinical presentations as well as impact on healthcare delivery. © 2017 Asian Pacific Society of Respirology.
Larval Chigger Mites Collected from Small Mammals in 3 Provinces, Korea
Lee, In-Yong; Song, Hyeon-Je; Choi, Yeon-Joo; Shin, Sun-Hye; Choi, Min-Kyung; Kwon, So-Hyun; Shin, E-Hyun; Park, Chan; Kim, Heung-Chul; Klein, Terry A.; Park, Kyung-Hee
2014-01-01
A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the predominant species in Hwaseong (95.8%) and Asan (61.2%), while Leptotrombidium scutellare was the predominant species collected from Jangseong (80.1%). Overall, larval chigger mite indices decreased from April (27.3) to June (4.9), then increased in September (95.2) and to a high level in November (169.3). These data suggest that L. pallidum and L. scutellare are the primary vectors of scrub typhus throughout their range in Korea. While other species of larval chigger mites were also collected with some implications in the transmission of Orientia tsutsugamushi, they only accounted for 11.2% of all larval chigger mites collected from small mammals. PMID:24850971
Chigger Mite (Acari: Trombiculidae) Survey of Rodents in Shandong Province, Northern China
Huang, Xiao-Dan; Cheng, Peng; Zhao, Yu-Qiang; Li, Wen-Juan; Zhao, Jiu-Xu; Liu, Hong-Mei; Kou, Jing-Xuan; Gong, Mao-Qing
2017-01-01
Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China (114–112°E, 34–38°N), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China. PMID:29103271
Chigger Mite (Acari: Trombiculidae) Survey of Rodents in Shandong Province, Northern China.
Huang, Xiao-Dan; Cheng, Peng; Zhao, Yu-Qiang; Li, Wen-Juan; Zhao, Jiu-Xu; Liu, Hong-Mei; Kou, Jing-Xuan; Gong, Mao-Qing
2017-10-01
Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China (114-112°E, 34-38°N), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China.
[Exanthematic typhus epidemic in Chile (1932-1939)].
Laval, Enrique
2013-06-01
After the great epidemic of the exanthematic typhus of 1918-1919 in Chile, there was a gradual decrease in the number of cases , until it became endemic around 1926. Starting in 1932 and until 1939 a new epidemic outbreak occured that prompted researchers to its study supported by the new clinical and technological advances of this period. Subsequently, two important events occured: the erradication of the vector ( human louse) by means of effective insecticides and the discovery of an effective antibiotic treatment.
Drought and Epidemic Typhus, Central Mexico, 1655–1918
Acuna-Soto, Rudofo; Stahle, David W.
2014-01-01
Epidemic typhus is an infectious disease caused by the bacterium Rickettsia prowazekii and transmitted by body lice (Pediculus humanus corporis). This disease occurs where conditions are crowded and unsanitary. This disease accompanied war, famine, and poverty for centuries. Historical and proxy climate data indicate that drought was a major factor in the development of typhus epidemics in Mexico during 1655–1918. Evidence was found for 22 large typhus epidemics in central Mexico, and tree-ring chronologies were used to reconstruct moisture levels over central Mexico for the past 500 years. Below-average tree growth, reconstructed drought, and low crop yields occurred during 19 of these 22 typhus epidemics. Historical documents describe how drought created large numbers of environmental refugees that fled the famine-stricken countryside for food relief in towns. These refugees often ended up in improvised shelters in which crowding encouraged conditions necessary for spread of typhus. PMID:24564928
Drought and epidemic typhus, central Mexico, 1655-1918.
Burns, Jordan N; Acuna-Soto, Rudofo; Stahle, David W
2014-03-01
Epidemic typhus is an infectious disease caused by the bacterium Rickettsia prowazekii and transmitted by body lice (Pediculus humanus corporis). This disease occurs where conditions are crowded and unsanitary. This disease accompanied war, famine, and poverty for centuries. Historical and proxy climate data indicate that drought was a major factor in the development of typhus epidemics in Mexico during 1655-1918. Evidence was found for 22 large typhus epidemics in central Mexico, and tree-ring chronologies were used to reconstruct moisture levels over central Mexico for the past 500 years. Below-average tree growth, reconstructed drought, and low crop yields occurred during 19 of these 22 typhus epidemics. Historical documents describe how drought created large numbers of environmental refugees that fled the famine-stricken countryside for food relief in towns. These refugees often ended up in improvised shelters in which crowding encouraged conditions necessary for spread of typhus.
Typhus fever: an overlooked diagnosis.
Mazumder, Ramendra N; Pietroni, Mark A C; Mosabbir, Nadira; Salam, M A
2009-06-01
A case of typhus fever is presented. On admission, the clinical diagnosis was typhoid fever. Forty-eight hours after admission, the presence of subconjunctival haemorrhage, malena, and jaundice raised the possibility of a different aetiology, the two most likely differentials being dengue and typhus. Finally, a co-infection of typhoid and typhus was discovered. This uncommon clinical scenario should be taken into account in the management of patients with high fever on admission being treated as a case of typhoid fever.
Analyzing the effectiveness of a frame-level redundancy scrubbing technique for SRAM-based FPGAs
Tonfat, Jorge; Lima Kastensmidt, Fernanda; Rech, Paolo; ...
2015-12-17
Radiation effects such as soft errors are the major threat to the reliability of SRAM-based FPGAs. This work analyzes the effectiveness in correcting soft errors of a novel scrubbing technique using internal frame redundancy called Frame-level Redundancy Scrubbing (FLR-scrubbing). This correction technique can be implemented in a coarse grain TMR design. The FLR-scrubbing technique was implemented on a mid-size Xilinx Virtex-5 FPGA device used as a case study. The FLR-scrubbing technique was tested under neutron radiation and fault injection. Implementation results demonstrated minimum area and energy consumption overhead when compared to other techniques. The time to repair the fault ismore » also improved by using the Internal Configuration Access Port (ICAP). Lastly, neutron radiation test results demonstrated that the proposed technique is suitable for correcting accumulated SEUs and MBUs.« less
Analyzing the effectiveness of a frame-level redundancy scrubbing technique for SRAM-based FPGAs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tonfat, Jorge; Lima Kastensmidt, Fernanda; Rech, Paolo
Radiation effects such as soft errors are the major threat to the reliability of SRAM-based FPGAs. This work analyzes the effectiveness in correcting soft errors of a novel scrubbing technique using internal frame redundancy called Frame-level Redundancy Scrubbing (FLR-scrubbing). This correction technique can be implemented in a coarse grain TMR design. The FLR-scrubbing technique was implemented on a mid-size Xilinx Virtex-5 FPGA device used as a case study. The FLR-scrubbing technique was tested under neutron radiation and fault injection. Implementation results demonstrated minimum area and energy consumption overhead when compared to other techniques. The time to repair the fault ismore » also improved by using the Internal Configuration Access Port (ICAP). Lastly, neutron radiation test results demonstrated that the proposed technique is suitable for correcting accumulated SEUs and MBUs.« less
Beyer, Andrea R; VieBrock, Lauren; Rodino, Kyle G; Miller, Daniel P; Tegels, Brittney K; Marconi, Richard T; Carlyon, Jason A
2015-10-01
A rising theme among intracellular microbes is the delivery of ankyrin repeat-containing effectors (Anks) that interact with target proteins to co-opt host cell functions. Orientia tsutsugamushi, an obligate intracellular bacterium and the etiologic agent of scrub typhus, encodes one of the largest Ank repertoires of any sequenced microorganism. They have been previously identified as type 1 secretion system substrates. Here, in silico and manual sequence analyses revealed that a large proportion of O. tsutsugamushi strain Ikeda Anks bear a eukaryotic/poxvirus-like F-box motif, which is known to recruit host cell SCF1 ubiquitin ligase machinery. We assessed the Anks for the ability to serve as F-box proteins. Coimmunoprecipitation assays demonstrated that F-box-containing Anks interact with overexpressed and/or endogenous SCF1 components. When coexpressed with FLAG-Ank4_01 or FLAG-Ank9, a glutathione S-transferase (GST)-tagged version of the SCF1 component SKP1 localized to subcellular sites of FLAG-Ank accumulation. The abilities of recombinant Anks to interact and colocalize with SKP1 were F-box dependent. GST-SKP1 precipitated O. tsutsugamushi-derived Ank9 from infected host cells, verifying both that the pathogen expresses Ank9 during infection and the protein's capability to bind SKP1. Aligning O. tsutsugamushi, poxviral, and eukaryotic F-box sequences delineated three F-box residues that are highly conserved and likely to be functionally important. Substitution of these residues ablated the ability of GFP-Ank9 to interact with GST-SKP1. These results demonstrate that O. tsutsugamushi strain Ikeda Anks can co-opt host cell polyubiquitination machinery, provide the first evidence that an O. tsutsugamushi Ank does so during infection, and advance overall understanding of microbial F-box proteins. Ankyrin repeat-containing proteins (Anks) are important virulence factors of intracellular bacteria that mediate protein-protein interactions with host cell targets. Orientia tsutsugamushi, which causes a debilitating infection called scrub typhus in one of the most densely populated regions of the world, encodes one of the largest Ank armamentariums of any sequenced bacterium. This study demonstrates that O. tsutsugamushi strain Ikeda Anks also bear F-box motifs that interact with host cell polyubiquitination machinery. By proving that an Orientia-derived Ank interacts with SKP1 in infected cells, this evidences the first bona fide Orientia effector and the first example of an endogenous F-box-containing Ank-mammalian-host ligand interaction for any intracellular bacterium. Also, importantly, this work identifies key residues that are essential for microbial F-box function. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Beyer, Andrea R.; VieBrock, Lauren; Rodino, Kyle G.; Miller, Daniel P.; Tegels, Brittney K.; Marconi, Richard T.
2015-01-01
ABSTRACT A rising theme among intracellular microbes is the delivery of ankyrin repeat-containing effectors (Anks) that interact with target proteins to co-opt host cell functions. Orientia tsutsugamushi, an obligate intracellular bacterium and the etiologic agent of scrub typhus, encodes one of the largest Ank repertoires of any sequenced microorganism. They have been previously identified as type 1 secretion system substrates. Here, in silico and manual sequence analyses revealed that a large proportion of O. tsutsugamushi strain Ikeda Anks bear a eukaryotic/poxvirus-like F-box motif, which is known to recruit host cell SCF1 ubiquitin ligase machinery. We assessed the Anks for the ability to serve as F-box proteins. Coimmunoprecipitation assays demonstrated that F-box-containing Anks interact with overexpressed and/or endogenous SCF1 components. When coexpressed with FLAG-Ank4_01 or FLAG-Ank9, a glutathione S-transferase (GST)-tagged version of the SCF1 component SKP1 localized to subcellular sites of FLAG-Ank accumulation. The abilities of recombinant Anks to interact and colocalize with SKP1 were F-box dependent. GST-SKP1 precipitated O. tsutsugamushi-derived Ank9 from infected host cells, verifying both that the pathogen expresses Ank9 during infection and the protein's capability to bind SKP1. Aligning O. tsutsugamushi, poxviral, and eukaryotic F-box sequences delineated three F-box residues that are highly conserved and likely to be functionally important. Substitution of these residues ablated the ability of GFP-Ank9 to interact with GST-SKP1. These results demonstrate that O. tsutsugamushi strain Ikeda Anks can co-opt host cell polyubiquitination machinery, provide the first evidence that an O. tsutsugamushi Ank does so during infection, and advance overall understanding of microbial F-box proteins. IMPORTANCE Ankyrin repeat-containing proteins (Anks) are important virulence factors of intracellular bacteria that mediate protein-protein interactions with host cell targets. Orientia tsutsugamushi, which causes a debilitating infection called scrub typhus in one of the most densely populated regions of the world, encodes one of the largest Ank armamentariums of any sequenced bacterium. This study demonstrates that O. tsutsugamushi strain Ikeda Anks also bear F-box motifs that interact with host cell polyubiquitination machinery. By proving that an Orientia-derived Ank interacts with SKP1 in infected cells, this evidences the first bona fide Orientia effector and the first example of an endogenous F-box-containing Ank–mammalian-host ligand interaction for any intracellular bacterium. Also, importantly, this work identifies key residues that are essential for microbial F-box function. PMID:26170417
Typhus Fever: An Overlooked Diagnosis
Mazumder, Ramendra N.; Mosabbir, Nadira; Salam, M.A.
2009-01-01
A case of typhus fever is presented. On admission, the clinical diagnosis was typhoid fever. Forty-eight hours after admission, the presence of subconjunctival haemorrhage, malena, and jaundice raised the possibility of a different aetiology, the two most likely differentials being dengue and typhus. Finally, a co-infection of typhoid and typhus was discovered. This uncommon clinical scenario should be taken into account in the management of patients with high fever on admission being treated as a case of typhoid fever. PMID:19507758
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, S. Y.
We propose using beam scrubbing to mitigate the electron cloud effect in the eRHIC. The bunch number is adjusted below the heat load limit, then it increases with the reduced secondary electron yield resulted from the beam scrubbing, up to the design bunch number. Since the electron density threshold of beam instability is lower at the injection, a preliminary injection scrubbing should go first, where large chromaticity can be used to keep the beam in the ring for scrubbing. After that, the beam can be ramped to full energy, allowing physics scrubbing. Simulations demonstrated that with beam scrubbing in amore » reasonable period of time, the eRHIC baseline design is feasible.« less
Reemerging threat of epidemic typhus in Algeria.
Mokrani, K; Fournier, P E; Dalichaouche, M; Tebbal, S; Aouati, A; Raoult, D
2004-08-01
We report a case of epidemic typhus in a patient from the Batna region of Algeria, who presented with generalized febrile exanthema. The clinical diagnosis was confirmed by serological cross-adsorption followed by Western blotting. Our report emphasizes the threat of epidemic typhus in the highlands of Algeria.
Shin, E-Hyun; Song, Bong Gu; Lee, Il Hee; Park, Mi Yeoun; Ahn, Young-Joon; Chang, Kyu-Sik
2013-05-01
Leptotrombidium pallidum (Nagoya, Miyagawa, Mitamura & Tamiya) is a primary vector of Orientia tsutsugamushi (Hyashi), the causative agent of scrub typhus. An assessment is made of the repellency to L. pallidum larvae (chiggers) of cassia bark, eucalyptus, and star anise oils and major constituents (E)-cinnamaldehyde, 1,8-cineole, and (E)-anethole of the corresponding oils. Results were compared with those of conventional repellents DEET (N,N-diethyl-3-methylbenzamide), IR3535 [(ethyl 3-[acetyl(butyl)amino]propanoate)], and permethrin. Based on the median repellent concentration (RC50) values, (E)-cinnamaldehyde, (E)-anethole, cassia bark oil, and star anise oil (RC50, 0.95-1.52 mg/cm2) exhibited significantly more potent repellency than DEET (3.85 mg/cm2). (E)-cinnamaldehyde, (E)-anethole, cassiabark oil, 1,8-cineole, and star anise oil were approximately 43, 16, 11, 8, and 4 times more effective than IR3535 (CC5, 6.51%) as judged by the median climbing distance-disturbing concentration (CC50) values. The median residual duration time of repellency (RT50) was significantly more pronounced in DEET (RT50, 323 min) than in all essential oils and constituents (108-167 min). In the light of global efforts to reduce the level of highly toxic synthetic repellents, the three essential oils and their major constituents described merit further study as potential biorepellents for the control of L. pallidum populations.
Murine Typhus, Reunion, France, 2011–2013
Camuset, Guillaume; Socolovschi, Cristina; Moiton, Marie-Pierre; Kuli, Barbara; Foucher, Aurélie; Poubeau, Patrice; Borgherini, Gianandrea; Wartel, Guillaume; Audin, Héla; Raoult, Didier; Filleul, Laurent; Parola, Philippe; Pagès, Fréderic
2015-01-01
Murine typhus case was initially identified in Reunion, France, in 2012 in a tourist. Our investigation confirmed 8 autochthonous cases that occurred during January 2011–January 2013 in Reunion. Murine typhus should be considered in local patients and in travelers returning from Reunion who have fevers of unknown origin. PMID:25625653
Bevacizumab in choroidal neovascularization secondary to Indian tick typhus: A rare case report.
Ijeri, Raghavendra; Beladiya, Gautam; Bhomaj, Sharad
2016-10-01
Tick typhus causes hemorrhagic lesions over the skin. Retina also shows hemorrhages and exudates. Many cases have been reported in western literature about this condition. To our best of knowledge, this is the first case report of tick typhus in India which was also associated with inflammatory choroidal neovascularization.
Epidemic typhus imported from Algeria.
Niang, M; Brouqui, P; Raoult, D
1999-01-01
We report epidemic typhus in a French patient returning from Algeria. The diagnosis was confirmed by serologic testing and the isolation of Rickettsia prowazekii in blood. Initially the patient was thought to have typhoid fever. Because body lice are prevalent in industrialized regions, the introduction of typhus to pediculosis-endemic areas poses a serious public health risk.
Clinical and laboratory features of murine typhus in central Tunisia: a report of seven cases.
Letaïef, A Omezzine; Kaabia, N; Chakroun, M; Khalifa, M; Bouzouaia, N; Jemni, L
2005-11-01
Murine or endemic typhus, caused by Rickettsia typhi, has been reported in all continents. In the 1970s, no cases of murine typhus were diagnosed in Tunisia. The clinico-epidemiological characteristics of seven cases of murine typhus diagnosed at our hospitals since 1993 are reported. Diagnosis was confirmed by indirect fluorescence assay detecting specific R. typhi antibodies. Murine typhus occurred in all ages from 18-80 years during the hot season in rural areas. Clinical features were: sudden onset of fever and absence of eschar in all cases, with maculo-papular rash (five cases), prostration (four cases), meningism (three cases) and pneumonia (four cases). Frequent laboratory findings were moderate thrombopenia (four cases) and elevated transaminases (four cases). Before the results of serology, clinical diagnoses were Mediterranean Spotted Fever (four cases), Q fever (one case), pneumonia (one case), and lymphocytic meningitis (one case). Serology confirmed all diagnoses with cross-reactivity with Rickettsia conorii. Murine typhus exists in Tunisia and its prevalence is underestimated. Further, more specific studies are needed to evaluate the true prevalence.
Ndihokubwayo, J B; Raoult, D
1999-01-01
Epidemic typhus is caused by a small strictly intracellular virus named Rickettsia prowazekii, a member of the Rickettsial family. It is transmitted to man by the body louse, Pediculus humanus. Although now rare in Western countries, exanthematic typhus remains common in the Southern hemisphere due to poverty, inadequate clothing hygiene, and poor socioeconomic conditions. In Africa, outbreaks have historically occurred in Burundi, Rwanda, southwest Ouganda, and Ethiopia. The largest outbreak of epidemic typhus since the World War II was reported in Burundi where ongoing civil war since October 1993 has forced 10 p. 100 of the population of Burundi to live in cold, promiscuity, and malnutrition of makeshift refugee camps. The purpose of this report based on our two-year experience working with this unfortunate population is to describe the characteristics of this disease in Africa where the epidemic form had become rare until recently. Indeed political unrest as well as numerous civil wars are now epidmiological factors favorizing outbreaks of epidemic typhus at any time. This overview also provides an opportunity to recall epidemiological, bacteriological, and clinical aspects of typhus as well as diagnosis and treatment of the disease in the context of Africa.
Fatal Flea-Borne Typhus in Texas: A Retrospective Case Series, 1985-2015.
Pieracci, Emily G; Evert, Nicole; Drexler, Naomi A; Mayes, Bonny; Vilcins, Inger; Huang, Philip; Campbell, Jill; Behravesh, Casey Barton; Paddock, Christopher D
2017-05-01
AbstractFlea-borne (murine) typhus is a global rickettsiosis caused by Rickettsia typhi . Although flea-borne typhus is no longer nationally notifiable, cases are reported for surveillance purposes in a few U.S. states. The infection is typically self-limiting, but may be severe or life-threatening in some patients. We performed a retrospective review of confirmed or probable cases of fatal flea-borne typhus reported to the Texas Department of State Health Services during 1985-2015. When available, medical charts were also examined. Eleven cases of fatal flea-borne typhus were identified. The median patient age was 62 years (range, 36-84 years) and 8 (73%) were male. Patients presented most commonly with fever (100%), nausea and vomiting (55%), and rash (55%). Respiratory (55%) and neurologic (45%) manifestations were also identified frequently. Laboratory abnormalities included thrombocytopenia (82%) and elevated hepatic transaminases (63%). Flea or animal contact before illness onset was frequently reported (55%). The median time from hospitalization to administration of a tetracycline-class drug was 4 days (range, 0-5 days). The median time from symptom onset to death was 14 days (range, 1-34 days). Flea-borne typhus can be a life-threatening disease if not treated in a timely manner with appropriate tetracycline-class antibiotics. Flea-borne typhus should be considered in febrile patients with animal or flea exposure and respiratory or neurologic symptoms of unknown etiology.
Association of Drought with Typhus Epidemics in Central Mexico
NASA Astrophysics Data System (ADS)
Acuna-Soto, R.; Stahle, D.; Villanueva Diaz, J.; Therrell, M.
2007-05-01
Typhus is an acute infectious disease caused by the bacteria Rickettsia prowazekii, which is transmitted among humans by the body lice (Pediculus humanus corporis). The disease is highly contagious and transmission is favored in populations living in crowded conditions. Under these circumstances, typhus transmission is facilitated by factors that favor the colonization and proliferation of body lice such as absence of personal hygiene and wearing the same clothes for long periods of time. Historically, periods of war and famine were associated with devastating epidemics with high mortality rates in many parts of the world. Central Mexico has a long record of typhus epidemics. In this region, at > 2000 meters above sea level, the disease was endemic and occurred with a seasonal pattern in winter, with occasional large epidemics. Recently, we completed a chronology of epidemics in Mexico. A total of 22 well-defined major typhus epidemics were identified between 1650 and 1920. All of them caused periods of increased mortality that lasted 2 - 4 years (more than one standard deviation from the previous ten year period). The record of typhus epidemics was evaluated against the tree-ring record of Cuauhtmoc La Fragua, Puebla. This chronology, based on Douglas fir, has demonstrated to be a faithful record of precipitation in central Mexico. The results indicate that a statistically significant drought (t test, p < .05) prevailed during the first year of all 22 large outbreaks of typhus in recent Mexican history. No distinction is made between times of peace and war. This indicates that drought alone was capable of inducing the social conditions for increased transmission of typhus in pre-industrial central Mexico.
Prusinski, Melissa A; White, Jennifer L; Wong, Susan J; Conlon, Maureen A; Egan, Christina; Kelly-Cirino, Cassandra D; Laniewicz, Brian R; Backenson, P Bryon; Nicholson, William L; Eremeeva, Marina E; Karpathy, Sandor E; Dasch, Gregory A; White, Dennis J
2014-04-01
Sylvatic typhus is an infrequent, potentially life-threatening emerging zoonotic disease. In January of 2009, the New York State Department of Health was notified of a familial cluster of two suspected cases. Due to the paucity of typhus cases in New York, epidemiologic and environmental investigations were conducted to establish rickettsial etiology and determine potential sources of infection. Patients presented with symptoms consistent with typhus, and serologic testing of each patient confirmed infection with typhus group rickettsiae. Serologic analysis of blood obtained from southern flying squirrels (Glaucomys volans) captured from the attic crawlspace above an enclosed front porch of the cases' residence indicated evidence of infection with Rickettsia prowazekii, with 100% seroprevalence (n=11). Both patients reported spending significant time on the porch and hearing animal activity above the ceiling prior to onset of illness, implicating these flying squirrels as the likely source of infection.
[Clinical features of four atypical pediatric cases of endemic typhus with pneumonia].
Liu, Jin-rong; Xu, Bao-ping; Li, Shao-gang; Liu, Jun; Tian, Bao-lin; Zhao, Shun-ying
2013-10-01
To analyze clinical manifestations, treatment and prognosis of 4 cases with endemic typhus. The clinical data of four endemic typhus patients in prognosis were retrospectively analyzed. These four atypical cases of endemic typhus with pneumonia were treated in our department from October 2011 to March 2012. They were all male, with an age range of 15 months to 7 years. The four patients had long history, mild respiratory symptom and no improvement was found after treatment with cephalosporins. There were no evidences of bacterial, viral, or fungal infections and we thought they might have infection with other pathogen. Three were from rural areas. Routine blood tests, Weil-Felix reaction, blood smear (Giemsa staining) , and indirect immunofluorescence assay were performed. Blood smear and IFA tests showed evidences for endemic typhus. The clinical presentations were atypical, the patients had no headache, but all had fever, rash, and pneumonia of varying severity. None of the patients had a severe cough, but bronchial casts were observed in one case. Recurrent fever was reported in three cases. Physical examinations showed no eschars, but one patient had a subconjunctival hemorrhage, and one had skin scratches, cervical lymphadenopathy, pleural effusion, pericardial effusion, and cardiac dilatation. Two patients had remarkably increased peripheral blood leukocyte counts; both these patients also had high alanine aminotransferase (ALT) levels and one had a high C-reactive protein (CRP) level. Weil-Felix testing was negative or the OX19 titer was low. The peripheral blood smear (Giemsa stain) showed intracellular pathogens in all four cases. After combined therapy with doxycycline and macrolide antibiotics, all four patients recovered well. The endemic typhus children often come from rural areas. The clinical presentations were atypical, they usually have no headache, but have fever (often Periodic fever) , rash, and pneumonia of varying severity in these four cases. Combined therapy with doxycycline and macrolide antibiotics was effective in all four patients.
Jeican, Ionuţ Isaia; Botiş, Florin Ovidiu; Gheban, Dan
2015-01-01
This article provides a picture of exanthematic Typhus in Romania during the Second World War: epidemiological aspects of this disease in the inner zone and in the zone of military operations, as well as information about the diagnosis, treatment and prophylaxis of the Typhus in our country during this period.
Severe interstitial pneumonia due to murine typhus in a patient returning from Bali.
Malheiro, Luís; Ceia, Filipa; Alves, João; Carvalho, Ana Cláudia; Sobrinho-Simões, Joana; Sousa, Rita; Sarmento, António; Santos, Lurdes
2017-01-01
Murine typhus has been increasingly reported as a cause of fever in returning travelers from Southeast Asia. We report a case of a previously healthy traveler returning from Bali with an non-specific febrile illness which quickly progressed to a severe form of interstitial pneumonia. After a careful epidemiological evaluation and laboratory analysis, murine typhus was diagnosed.
Typhus syncopalis: an epidemic in Connecticut in 1823.
Leng, Shirie C
2012-10-01
In 1825 Dr. Thomas Miner wrote about an epidemic that occurred in Middletown, Connecticut in 1823. He called this disease "Typhus syncopalis," sinking typhus, or New England spotted fever. Differences in the understanding of disease processes in the early 19th century preclude a definitive modern equivalent fortyphus syncopalis. In addition, there are disagreements among Dr. Miners' contemporaries with regard to fever classification systems. Examination of the symptoms and physical findings as described by Dr. Miner suggest the presence of encephalitis or meningitis as well as a syndrome resembling a shock-like state. Based on symptom comparisons, this paper suggests that typhus syncopalis was likely meningococcemia caused by Neisseria meningiditis.
Boev, B V; Lobanov, A V; Khudobin, V V
2008-01-01
Features of louse-borne typhus in Russia in the middle of 20th century are considered. Study of the infection source, blood serum in patient after epidemic louse-borne typhus (ELBT) and agent (louse) was performed on territory with high morbidity of pediculosis and ELBT in the years of 2nd world war. New materials of seroimmunological examinations are represented. Priority data of lice morphology based on morphometrical data of lice, collected in Russia and world collection in Berlin are shown. Methods of ELBT prediction are given, special attention is paid to development of mathematic prognostic models based on new technologies.
Mackenzie, Melville D.
1941-01-01
This paper deals with some aspects of the control of louse-borne typhus fever. The epidemic form is associated with famine and overcrowding. In producing an epidemic in a hitherto endemic area malnutrition is of greater importance than over-crowding; another factor which brings this about is widespread movement of civil or military population thus bringing non-immunes into a district where typhus is endemic. Endemic typhus usually occurs in the early months of the year, whilst the epidemic form may appear at any time. Conditions under which epidemic typhus occurs favour the outbreak of other diseases so that an uncomplicated case is rarely seen. Louse-borne typhus fever lasts from twelve to sixteen days. The incubation period is usually twelve to fourteen days, though it may be from five to twenty-one days. The onset is sudden, but is often preceded by malaise and a rise of temperature. Two common initial symptoms are acute frontal or occipital headache and bronchitis. The first sign may be mental confusion or delirium. Acute delirium is usually present after the first week. PMID:19992447
Malaria survey and malaria control detachments in the South-West Pacific Area in World War 2.
Crocker, Denton W
2009-01-01
Malaria among troops in the South-West Pacific Area (SWPA) in World War 2 affected the military effort to the degree that special units were formed to combat it. These malaria survey detachments (MSDs) and malaria control detachments (MCDs) were self-contained and so could move quickly to wherever their services were needed. In SWPA by 25 September 1944 there were 32 MSDs and 65 MCDs. Tables of organization called for 11 enlisted men in MSDs and MCDs, two officers in MSDs and one in MCDs. Detachments served throughout the SWPA. Detailed records of the 31st MSD show that in addition to antimalarial efforts it worked at control of scrub typhus, dengue and venereal disease, at reduction of rat populations and in experimental work involving DDT and schistosomiasis. Specific locations of the 31st MSD were New Guinea (3 sites), Morotai, Leyte, Mindoro, Okinawa and Japan. The detachment served overseas for 21 months. Experience in combating malaria in SWPA in World War 2 points to the need for better and continuous training of both medical and line officers in malaria prevention and control.
CKD and Infectious Diseases in Asia Pacific: Challenges and Opportunities.
Jha, Vivekanand; Prasad, Narayan
2016-07-01
The exact number of patients with chronic kidney disease (CKD) in Asia Pacific is uncertain. In numeric terms, the region is home to the largest population of patients with untreated chronic kidney failure. The climatic, geographic, social, cultural, economic, and environmental diversity within this region is higher than in any other part of the world. Large parts of the region face a climate-related burden of infectious diseases. Infections contribute to the development and progression of CKD and complicate the course of patients with pre-existing CKD (especially those on dialysis therapy or who are immunosuppressed), increase the cost of CKD care, and contribute to mortality and morbidity. Kidney involvement is a feature of several infectious diseases prevalent in Asia Pacific. Examples include malaria, leptospirosis, scrub typhus, tuberculosis, hepatitis B and C virus, dengue hemorrhagic fever, and Hantaan virus infections. The contribution of infection-associated acute kidney injury to the overall burden of CKD has not been evaluated systematically. Research is needed to quantify the impact of infections on kidney health by undertaking prospective studies. Nephrologists need to work with infectious disease research groups and government infection surveillance and control programs. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Frances, S P; Watcharapichat, P; Phulsuksombati, D; Tanskul, P; Linthicum, K J
1999-11-01
Leptotrombidium deliense Walch that attached to sentinel laboratory mice and the roof rat, Rattus rattus (L.), placed in an orchard habitat near Bangkok, Thailand, were studied between April 1993 and April 1995. A single L. deliense larva was attached to only 1 of 51 laboratory mice placed in the study area between April and September 1993. Overall, 89/202 (44.1%) R. rattus had 1 or more L. deliense larvae attached, and Orientia tsutsugamushi (Hayashi), the etiologic agent for scrub typhus, was isolated from liver/spleen samples of 2/202 (1.0%) rats placed in an endemic area for a single night. A total of 474 L. deliense attached to sentinel R. rattus, of which 314 larvae successfully fed to repletion and were recovered, and 2 (0.6%) of these were naturally infected with O. tsutsugamushi. The occurrence of L. deliense was influenced by rainfall, with more chiggers attached to rodents in the wetter months of the year. The study showed that the risk of exposure to infection with O. tsutsugamushi is greater during the wetter months of the year, and that only a relatively small number of chigger attachments are needed to infect potential hosts.
Moek, Felix; Poe, Poe; Charunwatthana, Prakaykaew; Pan-Ngum, Wirichada; Wattanagoon, Yupaporn; Chierakul, Wirongrong
2018-05-19
The clinical examination alone is widely considered unreliable when assessing fluid responsiveness in critically ill patients. Little evidence exists on the performance of the clinical examination to predict other hemodynamic derangements or more complex hemodynamic states. Patients with acute febrile illness were assessed on admission, both clinically and per non-invasive hemodynamic measurement. Correlations between clinical signs and hemodynamics patterns were analyzed, and the predictive capacity of the clinical signs was examined. Seventy-one patients were included; the most common diagnoses were bacterial sepsis, scrub typhus and dengue infection. Correlations between clinical signs and hemodynamic parameters were only statistically significant for Cardiac Index (r=0.75, p-value <0.01), Systemic Vascular Resistance Index (r=0.79, p-value <0.01) and flow time corrected (r=0.44, p-value 0.03). When assessing the predictive accuracy of clinical signs, the model identified only 62% of hemodynamic states correctly, even less if there was more than one hemodynamic abnormality. The clinical examination is not reliable to assess a patient's hemodynamic status in acute febrile illness. Fluid responsiveness, cardiodepression and more complex hemodynamic states are particularly easily missed.
Fatal Flea-Borne Typhus in Texas: A Retrospective Case Series, 1985–2015
Pieracci, Emily G.; Evert, Nicole; Drexler, Naomi A.; Mayes, Bonny; Vilcins, Inger; Huang, Philip; Campbell, Jill; Behravesh, Casey Barton; Paddock, Christopher D.
2017-01-01
Flea-borne (murine) typhus is a global rickettsiosis caused by Rickettsia typhi. Although flea-borne typhus is no longer nationally notifiable, cases are reported for surveillance purposes in a few U.S. states. The infection is typically self-limiting, but may be severe or life-threatening in some patients. We performed a retrospective review of confirmed or probable cases of fatal flea-borne typhus reported to the Texas Department of State Health Services during 1985–2015. When available, medical charts were also examined. Eleven cases of fatal flea-borne typhus were identified. The median patient age was 62 years (range, 36–84 years) and 8 (73%) were male. Patients presented most commonly with fever (100%), nausea and vomiting (55%), and rash (55%). Respiratory (55%) and neurologic (45%) manifestations were also identified frequently. Laboratory abnormalities included thrombocytopenia (82%) and elevated hepatic transaminases (63%). Flea or animal contact before illness onset was frequently reported (55%). The median time from hospitalization to administration of a tetracycline-class drug was 4 days (range, 0–5 days). The median time from symptom onset to death was 14 days (range, 1–34 days). Flea-borne typhus can be a life-threatening disease if not treated in a timely manner with appropriate tetracycline-class antibiotics. Flea-borne typhus should be considered in febrile patients with animal or flea exposure and respiratory or neurologic symptoms of unknown etiology. PMID:28500797
Yang, Wen; Huang, Jin-lou; Peng, Hui-qing; Li, Si-tuo
2013-09-01
Attrition scrubbing was used to remediate lead contaminated-site soil, and the main purpose was to remove fine particles and lead contaminants from the surface of sand. The optimal parameters of attrition scrubbing were determined by orthogonal experiment, and three soil samples with different lead concentration were subjected to attrition scrubbing experiments. The results showed that the optimal scrubbing parameters were: a solid ratio of 70% dry matter, a temperature of 25 degrees C, an attrition time of 30 min, and an attrition speed of 1200 r x min(-1). Before attrition scrubbing, the screening and analysis of soil showed that in all three soil samples, lead was mainly enriched on sand and fine particles, and the distribution of lead was highly correlated to the organic matter. After attrition scrubbing, the washing efficiency of the original state lead contaminated sand soil in triplicates was 67.61%, 31.71% and 41.01%, respectively, which indicates that attrition scrubbing can remove part of the fine soil and lead contaminants from the surface of sand, to accomplish the purpose of pollutants enrichment. Scanning electron microscopy (SEM) analysis showed that the sand surface became smooth after attrition scrubbing. The results above show that attrition scrubbing has a good washing effect for the remediation of lead contaminated sand soil.
JEICAN, IONUŢ ISAIA; BOTIŞ, FLORIN OVIDIU; GHEBAN, DAN
2015-01-01
This article provides a picture of exanthematic Typhus in Romania during the Second World War: epidemiological aspects of this disease in the inner zone and in the zone of military operations, as well as information about the diagnosis, treatment and prophylaxis of the Typhus in our country during this period. PMID:26528054
[Current problems in the laboratory control of louse-borne typhus infection in Ukraine].
Klymchuk, M D
1996-01-01
Surveys designed to study spread of typhus infection (persistent form and Brill's disease), and state of laboratory diagnosis in Ukraine showed an important role the laboratory diagnosis plays in the system of epidemiological surveillance aimed at preventing epidemic typhus. Main trends of activities on perfection of the system of laboratory control of the infection under present-day conditions are outlined.
Murine typhus in two travelers returning from Bali, Indonesia: an underdiagnosed disease.
Takeshita, Nozomi; Imoto, Kazuya; Ando, Shuji; Yanagisawa, Kunio; Ohji, Goh; Kato, Yasuyuki; Sakata, Akiko; Hosokawa, Naoto; Kishimoto, Toshio
2010-01-01
Two Japanese travelers from Bali were diagnosed with murine typhus in Japan during the same period. Although one had only mild illness, the other experienced liver and kidney dysfunction. Murine typhus may be missed not only in endemic areas around the world, but also in travelers, especially those returning from marine resorts in these areas. © 2010 International Society of Travel Medicine.
Avagard hand antisepsis vs. traditional scrub in 3600 pediatric urologic procedures.
Weight, Christopher J; Lee, Michael C; Palmer, Jeffrey S
2010-07-01
Avagard is a waterless, scrubless, and brushless hand antiseptic approved by the Food and Drug Administration as a replacement for traditional presurgical brush hand scrubbing. We evaluated the use of Avagard compared with hand brush scrub preparation for inpatient and outpatient pediatric urological operations. We evaluated the first 1800 patients for whom we used Avagard as a preoperative hand antiseptic and compared them with the last 1800 consecutive patients for whom we performed traditional antiseptic-impregnated hand-brush scrubbing. All patients underwent a variety of inpatient and outpatient open, endoscopic, and laparoscopic pediatric urological procedures. Patients were monitored postoperatively for wound infection, and patients and surgeon were monitored for side effects. A cost analysis was performed. The incidence of wound infection was 2/1800 (0.11%) in the Avagard group and 3/1800 (0.17%) in the hand-scrub group (P > .99 Fisher's exact test). All wound infections were successfully treated with a single course of oral antibiotics. No side effects for the patients or surgeon were noted, including skin irritations or allergic reactions in either group. The traditional hand scrub is nearly 2 times more expensive per application than Avagard. The incidence of wound infections in pediatric urological procedures is low (0.09%). We observe that Avagard provides comparable hand antisepsis to the traditional surgical scrub in a variety of pediatric urological procedures. Avagard is superior to the surgical hand scrub in cost-effectiveness and time efficiency. Urologists should consider using Avagard for hand antisepsis before surgery. Copyright 2010 Elsevier Inc. All rights reserved.
Moragues, Vicente; Pinkerton, Henry
1944-01-01
Murine typhus rickettsiae injected intraperitoneally in mice of the dba strain caused a uniformly fatal rickettsial peritonitis if the animals were kept at a room temperature ranging from 65–73°F. or from 70–80°F. With an environmental temperature range of 85–98°F., a mortality of less than 25 per cent was observed. By utilizing different strains of mice and controlling the environmental temperature, conditions may be created under which murine typhus will have any desired degree of mortality. Such conditions have obvious advantages for the evaluation of therapeutic measures in typhus infection. PMID:19871351
Scrubbing technique for needleless connectors to minimize contamination risk.
Satou, K; Kusanagi, R; Nishizawa, A; Hori, S
2018-03-21
This study aimed to investigate the appropriate scrubbing technique for needleless connectors to minimize contamination risk. To demonstrate a highly effective scrubbing technique to physically eliminate bacteria, needleless connectors were contaminated with Geobacillus stearothermophilus spores and then scrubbed. The study showed that the highest bacterial elimination rate was achieved by scrubbing an access port in a straight line with an alcohol cotton swab, applying a force that was almost equal to an arterial compression haemostasis to the access port, and repeating this procedure once using a new alcohol cotton swab. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Emerging vector-borne zoonoses: eco-epidemiology and public health implications in India.
Dhiman, Ramesh C
2014-01-01
The diseases originating from animals or associated with man and animals are remerging and have resulted in considerable morbidity and mortality. The present review highlights the re-emergence of emerging mainly zoonotic diseases like chikungunya, scrub typhus, and extension of spatial distribution of cutaneous leishmaniasis from western Rajasthan to Himachal Pradesh, Kerala, and Haryana states; West Nile virus to Assam, and non-endemic areas of Japanese encephalitis (JE) like Maharashtra and JE to Delhi; Crimean-Congo hemorrhagic fever making inroads in Ahmedabad; and reporting fifth parasite of human malaria with possibility of zoonosis have been highlighted, which necessitates further studies for prevention and control. Emphasis has been given on understanding the ecology of reservoir hosts of pathogen, micro niche of vector species, climatic, socioeconomic risk factors, etc. Development of facilities for diagnosis of virus from insects, reservoirs, and human beings (like BSL4, which has been established in NIV, Pune), awareness about symptoms of new emerging viral and other zoonotic diseases, differential diagnosis, risk factors (climatic, ecological, and socioeconomic) and mapping of disease-specific vulnerable areas, and mathematical modeling for projecting epidemiological scenario is needed for preparedness of public health institutes. It is high time to understand the ecological link of zoonotic or anthroponotic diseases for updated risk maps and epidemiological knowledge for effective preventive and control measures. The public health stakeholders in India as well as in Southeast Asia should emphasize on understanding the eco-epidemiology of the discussed zoonotic diseases for taking preventive actions.
Walker, D H; Popov, V L; Feng, H M
2000-09-01
A mouse model of typhus rickettsiosis that reproduces the hematogenous dissemination to the critical target organs, including brain, lungs, heart, and kidneys, primary endothelial and, to a lesser degree, macrophage intracellular rickettsial infection, and typical vascular-based lesions of louse-borne typhus and murine typhus was established. Intravenous inoculation of C3H/HeN mice with Rickettsia typhi caused disease with a duration of the incubation period and mortality rate that were dependent on the infective dose of rickettsiae. Lethal infection was associated with high concentrations of R. typhi in the lungs and brain, despite a brisker humoral immune response to the rickettsiae than in the sublethal infection. Gamma interferon and CD8 T lymphocytes were demonstrated to be crucial to clearance of the rickettsiae and recovery from infection in experiments in which specific monoclonal antibodies were administered to deplete these components. Death of animals depleted of gamma interferon or CD8 T lymphocytes was associated with overwhelming rickettsial infection demonstrated by titers of infectious rickettsiae and by immunohistochemistry. An effective antirickettsial immune response was associated with elevated serum concentrations of IL-12 on Day 5 and increased secretion of IL-12 by concanavalin-A-stimulated spleen cells on Day 5. Evidence for transient suppression of the immune response consisted of marked reduction in the secretion of IL-2 and IL-12 by concanavalin-A-stimulated spleen cells on Days 10 and 15. This model offers excellent opportunities for study of attenuation and pathogenetic mechanisms of typhus rickettsiae, which are established biologic weapons of potential use in bioterrorism.
INL DPAH STAAR 2015 Annual Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterman, Dean Richard
2015-09-15
Research conducted at the INL has demonstrated the synergistic extraction of americium using solvents comprised of bis(o,o-(trifluoromethyl)phenyl) dithiophosphinic acid (DPAH “1”) and trioctylphosphine oxide (TOPO), butyl bis(2,4,4-trimethylpentyl) phosphinate (BuCy272), or dibutyl butylphosphonate (DBBP). One potential drawback of this separations scheme is that soft metals such as silver, cadmium, or palladium and fission products such as zirconium are well extracted by these solvents. Several potential scrubbing reagents were examined. Of the scrubbing reagents studied, cysteine and methione exhibited some ability to scrub soft metals from the loaded solvent. More conventional scrub reagents such as ammonium fluoride or oxalic acid were notmore » effective. Reagents like Bimet and CDTA were not soluble at the acidities used in these studies. Unfortunately, these results indicate that the identification of effective scrubbing reagents for use in a flowsheet based upon the INL DPAH is going to be very difficult.« less
Jonke, A.A.
1957-10-01
In improved solvent extraction process is described for the extraction of metal values from highly dilute aqueous solutions. The process comprises contacting an aqueous solution with an organic substantially water-immiscible solvent, whereby metal values are taken up by a solvent extract phase; scrubbing the solvent extract phase with an aqueous scrubbing solution; separating an aqueous solution from the scrubbed solvent extract phase; and contacting the scrubbed solvent phase with an aqueous medium whereby the extracted metal values are removed from the solvent phase and taken up by said medium to form a strip solution containing said metal values, the aqueous scrubbing solution being a mixture of strip solution and an aqueous solution which contains mineral acids anions and is free of the metal values. The process is particularly effective for purifying uranium, where one starts with impure aqueous uranyl nitrate, extracts with tributyl phosphate dissolved in carbon tetrachloride, scrubs with aqueous nitric acid and employs water to strip the uranium from the scrubbed organic phase.
A stranger to our camps: Typhus in American history.
Humphreys, Margaret
2006-01-01
Medical observers during the American Civil War were happily surprised to find that typhus fever rarely made an appearance, and was not a major killer in the prisoner-of-war camps where the crowded, filthy, and malnourished populations appeared to offer an ideal breeding ground for the disease. Through a review of apparent typhus outbreaks in America north of the Mexican border, this article argues that typhus fever rarely if ever extended to the established populations of the United States, even when imported on immigrant ships into densely populated and unsanitary slums. It suggests that something in the American environment was inhospitable to the extensive spread of the disease, most likely an unrecognized difference in the North American louse population compared to that of Europe.
The history of epidemic typhus.
Raoult, Didier; Woodward, Theodore; Dumler, J Stephen
2004-03-01
Few infectious diseases have influenced human civilization to the same degree as louse-transmitted typhus. Rickettsia prowazekii continues to strikes tens to hundreds of thousands of persons who live with war, famine, crowding, and in squalid conditions associated with social unrest, with mortality rates in excess of 10% to 15%. Historical documents confirm that such devastation has been a continuous feature of human existence to the extent that typhus has been a major determinant in the outcome of many wars, altering human history in its wake-despite incomplete knowledge of its precise origin. In the twenty-first century, circumstances are still conductive for outbreak; the emerging threat of bioterrorism raises justifiable concerns that typhus could affect civilization just as greatly in the future as it has in the past.
Choi, Jeong Sil
2008-02-01
The purpose of this study was to compare 1% chlorhexidine-gluconate/61% ethanol (CHG/Ethanol) emollient and 7.5% povidone-iodine (PVI) scrub for antimicrobial,residual effect, and skin condition. CHG/Ethanol emollient hand hygiene was performed waterless, and brushless by operating doctors and nurses (N=20). PVI hand washing was performed with water and a brush (N=20) for 5 min. The subjects were asked to press their left hand in hand-shaped agar before a surgical scrub, immediately after a surgical scrub and after the operation. The amount of isolated microorganisms were calculated by counting the number of divided areas(1 x 1 cm, 160 cell) which were culture positive in the hand culture plate. The skin condition was evaluated. The antimicrobial count of CHG/Ethanol emollient and PVI immediately post surgical scrub was 0.0 vs. 4.1 (p>.05), and after the operation was 0.1 vs. 37.8 (p>.05)respectively. The Residual effect of CHG/Ethanol emollient immediately post surgical scrub and after the operation were 0.0 vs. 0.1 (p>.05), and PVI were 4.1 vs. 37.8 (p>.05)respectively. The skin condition and satisfaction of CHG/Ethanol emollient was higher than PVI (p<.05). The antimicrobial effect between CHG/Ethanol emollient and PVI were the same. Considering skin condition, satisfaction and allergic reaction CHG/Ethanol emollient for surgical scrub is recommended in Korea.
Significance of major international seaports in the distribution of murine typhus in Taiwan.
Kuo, Chi-Chien; Wardrop, Nicola; Chang, Chung-Te; Wang, Hsi-Chieh; Atkinson, Peter M
2017-03-01
International seaports are hotspots for disease invasion and pathogens can persist in seaports even after ports are abandoned. Transmitted by fleas infected by Rickettsia typhi, murine typhus, a largely neglected and easily misdiagnosed disease, is known to occur primarily in large seaports. However, the significance of seaports in the occurrence of murine typhus has never been validated quantitatively. We studied the spatial distribution of murine typhus, a notifiable disease, in Taiwan. We investigated whether risk of infection was correlated with distance to international seaports and a collection of environmental and socioeconomic factors, using a Bayesian negative binomial conditionally autoregressive model, followed with geographically weighted regression. Seaports that are currently in use and those that operated in the 19th century for trade with China, but were later abandoned due to siltation were analyzed. A total of 476 human cases of murine typhus were reported during 2000-2014 in the main island of Taiwan, with spatial clustering in districts in southwest and central-west Taiwan. A higher incidence rate (case/population) was associated with a smaller distance to currently in-use international seaports and lower rainfall and temperature, but was uncorrelated with distance to abandoned ports. Geographically weighted regression revealed a geographic heterogeneity in the importance of distance to in-use seaports near the four international seaports of Taiwan. Our study suggests that murine typhus is associated with international seaports, especially for those with large trading volume. Thus, one of the costs of global trade in Taiwan might be elevated risks of murine typhus. Globalization has accelerated the spread of infectious diseases, but the burden of disease varies geographically, with regions surrounding major international seaports warranting particular surveillance.
Significance of major international seaports in the distribution of murine typhus in Taiwan
Wardrop, Nicola; Chang, Chung-Te; Wang, Hsi-Chieh; Atkinson, Peter M.
2017-01-01
Background International seaports are hotspots for disease invasion and pathogens can persist in seaports even after ports are abandoned. Transmitted by fleas infected by Rickettsia typhi, murine typhus, a largely neglected and easily misdiagnosed disease, is known to occur primarily in large seaports. However, the significance of seaports in the occurrence of murine typhus has never been validated quantitatively. Methodology/Principal findings We studied the spatial distribution of murine typhus, a notifiable disease, in Taiwan. We investigated whether risk of infection was correlated with distance to international seaports and a collection of environmental and socioeconomic factors, using a Bayesian negative binomial conditionally autoregressive model, followed with geographically weighted regression. Seaports that are currently in use and those that operated in the 19th century for trade with China, but were later abandoned due to siltation were analyzed. A total of 476 human cases of murine typhus were reported during 2000–2014 in the main island of Taiwan, with spatial clustering in districts in southwest and central-west Taiwan. A higher incidence rate (case/population) was associated with a smaller distance to currently in-use international seaports and lower rainfall and temperature, but was uncorrelated with distance to abandoned ports. Geographically weighted regression revealed a geographic heterogeneity in the importance of distance to in-use seaports near the four international seaports of Taiwan. Conclusions/Significance Our study suggests that murine typhus is associated with international seaports, especially for those with large trading volume. Thus, one of the costs of global trade in Taiwan might be elevated risks of murine typhus. Globalization has accelerated the spread of infectious diseases, but the burden of disease varies geographically, with regions surrounding major international seaports warranting particular surveillance. PMID:28264003
[An outbreak of epidemic louse-borne typhus in Tokyo 1914: a study on the prevention of epidemics].
Watanabe, Mikio
2002-12-01
In 1914, the third year of the Taisho era, a period of democracy and prosperity of Japan, Tokyo was attached by an outbreak of epidemic louse-borne typhus. The number of patients was 4,119 and number of deaths was 778 (mortality rate of 18.9%) in Tokyo and 7,309 patients had been suffering from typhus fever that year in Japan. Many possible causes of the outbreak were suspected by the Health Authority of the Home Office, but these were not confirmed. One of the most likely reasons is the poor and congested living conditions of seasonal construction workers. Laborers had moved from the northwest region of Japan where typhus fever had developed occasionally in those days. Some of the laborers probably brought pathogenic germs with lice. The main preventive method for epidemic louse-borne typhus was isolation of patients and disinfecting of the areas. Kitasato Shibasaburou proposed the improvement of residential conditions of workers to prevent the prevalence of disease, but the proposal was not accepted because of financial reasons of the government. Recurrence of the outbreak did not occur in the following years. However, a huge outbreak of typhus fever with 32,366 patients and 3,351 deaths, was documented in 1946, amidst the disordered conditions of Japan after World War II.
[Poland: cholera to typhus, 1831-1950].
Balinska, M A
1999-12-01
In this article devoted to Poland's direct and indirect role in the elaboration of contemporary international health structures and to her reputation as an epidemic reservoir of Europe, we consider how Poland came to be perceived as the cordon sanitaire of the West. Traditionally seen as upholding Western values, in the 19th and 20th centuries the country became increasingly associated with "Eastern plagues"-cholera and then typhus-coming from Russia and which could spread to the rest of Europe if Poland did not manage to contain them. When Poland was reconstituted as a nation-state in 1918, the new country won international recognition through her successful attempts to contain a typhus epidemic sweeping westwards from Russia. The Polish government convened the first European, League sponsored, health conference following the First World War. A Polish doctor, L. RAJCHMAN, was chosen to head up the League of Nations Health Organisation (forerunner of the WHO) and later (1946) founded UNICEF. Finally, we examine the key issue of exanthematous typhus in both world wars, exemplifying how a disease can come to be "ideologized", in this case by Nazi Germany. Typhus was the pretext used- in the name of "public health"-for segregating Polish citizens of Jewish origin and even killing them. Paradoxically, typhus was in the process of being eradicated when the war began and German policy of mass resettlements, sequestration, and starvation only spurred the epidemic they supposedly wished to control.
A System Approach to Navy Medical Education and Training. Appendix 21. Orthopedic Technician.
1974-08-31
33 1AMPUTATION SCRUB 34 IDISARTICULATION SCRUB 35 IARTHRODESIS SCRUB 36 ITRIPLE ARTHRODESIS SCRUB 37 IMENISECTOMY SCRUP 38 IOPEN REDUCTION OF...FRACTURES SCRUB 39 ISPINAL FUSION SCRUB 40 IHIP NAILING SCRUB 41 IINSERTION OF ORTHOPEDIC PINS, NAILS SCRUB 42 1EXTRACTION OF ORTHOPEDIC PINS SCRUB 43 IBONE...ITENDON TRANSFER SCRUB 48 IBUNIONECTOMY SCRUB 9 ISOUTHWICK PROCEDURE KNEE SCRUB 50 MAGUSON-STOCK REPAIR OF SHOULDER SCRUB TURN PAGE LEFT PAGE 04 ORTHO
2010-01-01
MediCine and Hyg1cne Epidemiology of Spotted Fever Group and Typhus Group Rickettsial Infection in the Amazon Basin of Peru Brett M. Forshey, Allison...approximately 4% of acute febrile episodes detected in Iquitos, a city located in the Amazon region of northeast- ern Peru , could be attributed to SFGR...2010 to 00-00-2010 4. TITLE AND SUBTITLE Epidemiology Of Spotted Fever Group And Typhus Group Rickettsial Infection In The Amazon Basin Of Peru 5a
Tarasevich, I V; Shpynov, S N; Pantyukhina, A N
2015-01-01
Materials, that summarize data of original research and scientific literature on epidemiology and problems of persistence during epidemic typhus, whose causative agent (Rickettsia prowazekii) is reactivated in the organism of the previously ill and is manifested as Brill-Zinser disease, are presented. A retrospective analysis was carried out with the data obtained by Russian (All-Union) Centre for Rickettsioses during study of epidemiologic examination maps of 5705 typhus nidi and results of 19 463 blood sera analysis during study of immunologic structure of population in the territories of the former USSR for the period from 1970 to 1992. A decrease of epidemic typhus morbidity and an increase of the fraction of Brill-Zinser disease took place as a result of pediculosis corporis control. In separate territories specific weight of Brill-Zinser disease was 48% in 1952, up to 80% in 1969, and from 1977 all the ill were previously ill. However, during the perestroika period and afterwards, due to a reduction of economic and hygienic living conditions, appearance of refugees, the immune structure regarding typhus began to change. Due to the buildup of the population migration process and the presence of risk groups (refugees, homeless) among population of regions, where local wars are waged, the enhancement of methods of epidemic typhus and Brill-Zinser disease diagnostics and pediculosis corporis eradication is necessary. Study of R. prowazekii by molecular-genetics methods is necessary for complete understanding of its mechanism of persistence.
[The role of Turkish physicians in the vaccination against typhus during the years of World War I].
Karatepe, Mustafa
2008-04-01
During the years of World War I, several severe typhus epidemics were seen in Erzurum and nearby cities. A total of 164 health officers, 125 of whom were physicians, struggled against the epidemic in the region but also they lost their lives due to typhus. Vaccination against typhus was one of the means of fighting the epidemic. However, there were some claims that a small group of Turkish physicians injected typhus-contaminated serum into Armenian civilians during World War I, and that this should be accepted as a form of biological warfare against Armenian civilians. The purpose of this article is to set out how, by whom, and on whom, and under what conditions the typhus vaccination was applied in order to reveal the truth in terms of the evidence found in historical documents. The typhus vaccine was prepared from blood taken from febrile patients affected by the disease. After the blood of the patients were defibrinated and inactivated at 60 degrees C for an hour, it was used. As the amount of blood needed to prepare the vaccine was so great, the amount of available vaccine was always insufficient to meet the demand. Hence, the prepared vaccine was only applied to those which had the higher risk of contracting typhus such as physicians and nurses. The vaccine prepared by The Third Army Health Commander Dr. Tevfik Salim was first applied to nine officers, five of whom were physicians, and among whom were Dr. Haydar Cemal and Dr. Salahattin on March 28, 1915 in Hasankale, Erzurum. Furthermore, the same vaccine was applied to people in the vicinity by Dr. Alaattin in Erzurum, Dr. Abdulhalim Asim in Bayburt, Dr. Izak in Sivas and Dr. Mihran in Hasankale. Ali Ihsan Sabis and Fevzi Cakmak, who were high ranking officers, were among those who volunteered to have the vaccination. The Third Army Health Commander Dr. Tevfik Salim ordered that the vaccine should not be applied without blood inactivation. Despite this order, Dr. Hamit Osman, who had a mental illness, applied the vaccination without inactivating the blood to some people. Among those were physicians of the Red Crescent Hospital together with soldiers who were nursing in the hospitals in Erzincan. Dr. Hamdi Suat inactivated the blood by leaving it at -16 degrees C for 24-48 hours, and instead of giving a single dose, he applied three-doses with 3-day-intervals, followed by a one more dose, which he called "the vaccine for absolute immunization" to the same people after 10-23 days. This "vaccine for absolute immunization" was actually typhus-contaminated blood which had not been inactivated. It should be noted that he injected himself with the same form of vaccine. In his article published in German in 1916 and in Turkish in 1917, he stated that he injected "the vaccine for absolute immunization" to some subjects 'condemned to death'. Dr. Haydar Cemal claimed, in a newspaper dated December 23, 1918, that the people reported as subjects 'condemned to death' were indeed Armenians, and that the innocent Armenians marked out for deportation were inoculated with the blood of typhus fever patients, and that he eyewitnessed all these events. As a result of his claims, the Interior Ministry demanded an immediate investigation, and at the end of that investigation it was understood that Dr. Haydar Cemal and Dr. Hamdi Suat had never worked together in Erzincan at the time Dr. Haydar Cemal claimed. All the claims were refuted by the investigating committee and nobody was charged. During a severe typhus epidemic, Turkish physicians injected the typhus vaccine for the purpose of "saving a life from the fire". The typhus vaccine was prepared using the available scientific knowledge of the time. No racial or religious discrimination against the people vaccinated had been proved. According to the sources, the claim that some Turkish physicians used the blood of patients with typhus as a means of biological warfare does not reflect the historical truth.
Mulberrry, G; Snyder, A T; Heilman, J; Pyrek, J; Stahl, J
2001-12-01
A new waterless surgical hand preparation containing 1% chlorhexidine gluconate (CHG) and 61% ethyl alcohol was evaluated for antimicrobial efficacy in comparison with a standard 4% CHG surgical scrub and a 61% ethyl alcohol control. Clinical studies were based on the Tentative Final Monograph for Health-Care Antiseptic Drug Products (TFM) (proposed rule) and the Standard Test Method for Evaluation of Surgical Hand Scrub Formulations (ASTM E1115-91). Two randomized, blinded, well-controlled clinical studies involving 137 healthy subjects were conducted to evaluate the antimicrobial effectiveness of the CHG/ethanol hand preparation in producing an immediate and persistent reduction in the normal bacterial flora of the hands. The CHG/ethanol hand preparation was applied without scrubbing or the use of water, and a standard 4% CHG reference product was applied with a scrub brush in 2 traditional 3-minute surgical scrubs. In 1 study, a 61% ethanol vehicle control treatment was applied without scrubbing or use of water. During a 5-day period, each study subject performed a series of 11 surgical scrubs with 1 of the test treatments. After the first treatment on days 1, 2, and 5, surgical gloves were worn for 3 or 6 hours. Bacterial samples were taken with the glove-juice technique at 1 minute, 3 hours, and 6 hours after treatment. The immediate bactericidal effect of the CHG/ethanol hand preparation after a single application resulted in a 2.5-log reduction in normal flora. This bactericidal effect persisted throughout the studies and eventually increased to a 3.6-log reduction after the 11th scrub on day 5. The log reductions of the CHG/ethanol hand preparation proved to be significantly better (P <.05) than that of the 4% CHG product at each sampling interval on days 1 and 2 and the sampling at 6 hours on day 5 and significantly better than the 61% ethanol vehicle at all times. The combination of 1% CHG and 61% ethanol had significantly greater microbial reduction than either the 4% CHG (without ethanol) or the 61% ethanol vehicle (without CHG).
[Petechial typhus. History of men, armies and pedicula].
Sabbatani, Sergio
2006-09-01
Since the Classical age, humankind has had to cope with petechial typhus, especially during wars and famine. Epidemics chiefly occurred during sieges and followed the paths of armies, when infected soldiers transmitted the infection to populations with whom they came into contact. Winter exacerbated the disease due to the use of unhygienic woollen clothes that allowed the spread of pediculosis. It was only in the early 18th century that petechial typhus outbreaks diminished thanks to the use of Marseille soap and to the new custom of changing clothing at bedtime. In many military campaigns, deaths from typhus were higher than those due to war wounds: recent studies established that the French defeat during the Napoleonic Russian military campaign has to be attributed more to typhus than to the military superiority of the enemy. Indeed, the contagion is estimated to have affected 80% of the 600,000 troops involved. The role of Pediculus as a vehicle of infection established in 1909 by Charles Nicolle, microbiological isolation performed by Howard Ricketts and Stanislaus von Prowazck, and finally the advent of antibiotic therapy, all laid the basis for controlling the disease in the 20th century.
Distribution of tick-borne diseases in Japan: Past patterns and implications for the future.
Yamaji, Kayoko; Aonuma, Hiroka; Kanuka, Hirotaka
2018-04-20
The rapid geographical spread of tick-borne diseases (TBDs) worldwide has recently provoked significant concerns amongst public health authorities. Tick-borne pathogens are maintained in enzootic cycles involving ticks and wild animal hosts, with epizootic spread to other mammals, including livestock and humans. Despite the increasing public health concern, current TBD diagnostic tests and treatments are inadequate, and predictive models of future risks posed by TBDs are limited by the heterogeneity of environmental, vector, and host factors, even in neighboring regions. In recent years, infections resulting in severe fever with thrombocytopenia syndrome (SFTS), Japanese spotted fever, and the scrub typhus pathogens have been reported frequently in addition to traditional TBDs in Japan. The Japanese archipelago is extremely elongated from north to south and its climate varies considerably, creating remarkable regional differences in tick species. The importance of continuous surveillance of TBDs has been growing in terms of geopathology - studies dealing with the relationships between geographic factors and the causes of specific diseases - in Japan and neighboring areas among eastern Asian countries, including China and Korea. In this review, we summarize detailed information regarding the history and epidemic status of human TBDs in Japan. Copyright © 2018 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Tarantola, Arnaud; Goutard, Flavie; Newton, Paul; de Lamballerie, Xavier; Lortholary, Olivier; Cappelle, Julien; Buchy, Philippe
2014-01-01
Diverse aetiologies of viral and bacterial encephalitis are widely recognized as significant yet neglected public health issues in the Mekong region. A robust analysis of the corresponding health burden is lacking. We retrieved 75 articles on encephalitis in the region published in English or in French from 1965 through 2011. Review of available data demonstrated that they are sparse and often derived from hospital-based studies with significant recruitment bias. Almost half (35 of 75) of articles were on Japanese encephalitis virus (JEV) alone or associated with dengue. In the Western Pacific region the WHO reported 30,000–50,000 annual JEV cases (15,000 deaths) between 1966 and 1996 and 4,633 cases (200 deaths) in 2008, a decline likely related to the introduction of JEV vaccination in China, Vietnam, or Thailand since the 1980s. Data on dengue, scrub typhus and rabies encephalitis, among other aetiologies, are also reviewed and discussed. Countries of the Mekong region are undergoing profound demographic, economic and ecological change. As the epidemiological aspects of Japanese encephalitis (JE) are transformed by vaccination in some countries, highly integrated expert collaborative research and objective data are needed to identify and prioritize the human health, animal health and economic burden due to JE and other pathogens associated with encephalitides. PMID:24498443
Outbreak of Human Brucellosis from Consumption of Raw Goats' Milk in Penang, Malaysia.
Leong, Kar Nim; Chow, Ting Soo; Wong, Peng Shyan; Hamzah, Siti Hawa; Ahmad, Norazah; Ch'ng, Chin Chin
2015-09-01
We report the largest outbreak of brucellosis in Penang, Malaysia. Brucellosis is not endemic in this region. The index case was a 45-year-old goat farm owner presented with 3 weeks of fever, headache, severe lethargy, poor appetite, and excessive sweating. He claimed to have consumed unpasteurized goat's milk that he had also sold to the public. Tests were negative for tropical diseases (i.e., dengue fever, malaria, leptospirosis and scrub typhus) and blood culture showed no growth. Based on epidemiological clues, Brucella serology was ordered and returned positive. Over a period of 1 year, 79 patients who had consumed milk bought from the same farm were diagnosed with brucellosis. Two of these patients were workers on the farm. Four laboratory staff had also contracted the disease presumably through handling of the blood samples. The mean duration from onset of symptoms to diagnosis was 53 days with a maximum duration of 210 days. A combination treatment of rifampin and doxycycline for 6 weeks was the first line of treatment in 90.5% of patients. One-third of the patients had sequelae after recovering and 21% had a relapse. We highlight the importance of Brucellosis as a differential diagnosis when a patient has unexplained chronic fever. © The American Society of Tropical Medicine and Hygiene.
Seasonal development of Leptotrombidium akamushi (Acari: Trombiculidae) under field temperatures.
Takahashi, M; Morita, K; Tsuji, O; Misumi, H; Otsuji, J; Hori, E; Kawanura, A; Tanaka, H
1995-11-01
Engorged larvae of Leptotrombidium akamushi (Brumpt), a vector of scrub typhus, were reared in small plastic containers placed on the ground and fed fresh eggs of the collembolan Sinella curviseta Brook. Engorged larvae obtained in October developed into deutonymphs through protonymphs approximately 1 mo before winter and became dormant in the cold winter season (approximately 3 mo). Most deutonymphs developed into tritonymphs in April and adults in May. Females began laying eggs in mid-June and the numbers of unfed larvae showed a peak in August. The mites reared from July rapidly developed into adults by August, and laid eggs in September. Larvae were most abundant in October, and adults became dormant in the winter. The same adults laid eggs from early May to late June and, upon hatching, the larval population peaked in early July of the 2nd summer. Most larvae died before the 2nd winter. Eggs hatched approximately 3 wk after oviposition and longevity of unfed larvae was 2 mo. Because of this very short incubation period, L. akamushi larvae occur in the summer, whereas L. pallidum Nagayo, Miyagawa, Mitamura & Tamiya, and L. scutellare Nagayo, Miyagawa, Mitamura, Tamiya & Tenjin occur in the autumn, although 3 species lay eggs from May to August.
Chung, Lo-Hsuan; Wu, Wen-Jer; Kuo, Chi-Chien; Wang, Hsi-Chieh
2015-11-01
Scrub typhus is a lethal human disease transmitted by larval trombiculid mites (i.e., chiggers) that have been infected with the rickettsia Orientia tsutsugamushi. In total, 21 chigger species are known from Taiwan. We update the checklist of chiggers of Taiwan based on an intensive survey of shrew and rodent hosts in grasslands and agricultural fields in lowland Taiwan, coupled with surveys of forests in one mountainous site and an opportunistic examination of submitted host specimens. Three new species of chiggers, Gahrliepia (Gateria) lieni sp. n., Gahrliepia (Gateria) minuta sp. n., and Gahrliepia (Gateria) yilanensis sp. n., as well as 23 newly recorded chigger species, were discovered. Accordingly, recorded chigger species of Taiwan more than doubled from 21 to 47 species. Two new species and nine newly recorded chigger species were discovered in forests in one mountainous site in northeastern Taiwan, suggesting that many more chigger species may be uncovered, particularly in mountainous Taiwan. Further studies should also investigate O. tsutsugamushi infection in different chigger species to assess its risks to human health. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Detection of a typhus group Rickettsia in Amblyomma ticks in the state of Nuevo Leon, Mexico.
Medina-Sanchez, Aaron; Bouyer, Donald H; Alcantara-Rodriguez, Virginia; Mafra, Claudio; Zavala-Castro, Jorge; Whitworth, Ted; Popov, Vsevolod L; Fernandez-Salas, Ildefonso; Walker, David H
2005-12-01
The state of Nuevo Leon, Mexico has had outbreaks of typhus group rickettsiosis, most recently recognized in 1997. Evaluation of the sera of 345 patients with a dengue-like illness revealed that 25.5% had antibodies reactive with typhus group rickettsiae and 16% had antibodies to Rickettsia parkeri. Rickettsiae were detected by PCR and shell-vial isolations in the field-collected Amblyomma ticks. Molecular characterization by DNA sequence analysis of the gltA, ompB, and 17-kDa gene identified the organisms to be R. prowazekii.
Snyder, J. C.; Wheeler, C. M.
1945-01-01
Experiments are described which demonstrate that human body lice (Pediculus humanus corporis), were infected experimentally with murine and epidemic louse-borne strains of typhus fever by feeding on suitably prepared rabbits. Details of the two methods of infection, the "bleb technique" and the "I.V. technique," are presented. It is concluded that the experimental infection of human lice with typhus can be accomplished very easily and rapidly with these methods. The possible applications of the method are discussed. PMID:19871482
David I. King; Richard B. Chandler; Jeffrey M. Collins; Wayne R. Petersen; Thomas E. Lautzenheiser
2009-01-01
Concern about declines in scrubâshrub bird populations has resulted in efforts to create and maintain habitat for these species. Vegetation within powerline corridors is managed to prevent contact of vegetation with transmission lines, and comprises approximately 2% of all of habitat for scrubâshrub birds in southern New England. Although previous studies have...
In vitro and in vivo killing of ocular Demodex by tea tree oil
Gao, Y-Y; Di Pascuale, M A; Li, W; Baradaran-Rafii, A; Elizondo, A; Kuo, C-L; Raju, V K; Tseng, S C G
2005-01-01
Aims: To compare the in vitro killing effect of different agents on Demodex and to report the in vivo killing effect of tea tree oil (TTO) on ocular Demodex. Methods: Survival time of Demodex was measured under the microscope. Sampling and counting of Demodex was performed by a modified method. Results: Demodex folliculorum survived for more than 150 minutes in 10% povidone-iodine, 75% alcohol, 50% baby shampoo, and 4% pilocarpine. However, the survival time was significantly shortened to within 15 minutes in 100% alcohol, 100% TTO, 100% caraway oil, or 100% dill weed oil. TTO’s in vitro killing effect was dose dependent. Lid scrub with 50% TTO, but not with 50% baby shampoo, can further stimulate Demodex to move out to the skin. The Demodex count did not reach zero in any of the seven patients receiving daily lid scrub with baby shampoo for 40–350 days. In contrast, the Demodex count dropped to zero in seven of nine patients receiving TTO scrub in 4 weeks without recurrence. Conclusions: Demodex is resistant to a wide range of antiseptic solutions. Weekly lid scrub with 50% TTO and daily lid scrub with tea tree shampoo is effective in eradicating ocular Demodex. PMID:16234455
Moisturizing alcohol hand gels for surgical hand preparation.
Jones, R D; Jampani, H; Mulberry, G; Rizer, R L
2000-03-01
With the use of novel formulary technology, unique moisturizing hand gels have been developed that offer significant advantages in perioperative and other health care settings. These advantages include the time-saving capabilities of a waterless formulation, the persistence and effectiveness of a surgical scrub, and the moisturization and protective properties of a lotion. Extensive laboratory and clinical studies, involving in vivo antimicrobial activity against resident and transient flora, skin moisturization on normal and dry skin, and compatibility with latex gloves, have supported these advantages. Nondrying alcohol hand gels can be used for antiseptic hand washing, hand scrubs between procedures (i.e., reentry scrubs), brushless surgical scrubs, moisturizers, and glove-donning aids.
[The eagle and the louse: typhus in the Grand Army].
Ducoulombier, Henri
2014-01-01
How is it that lice, such a common parasite, have shaken the Napoleonic empire? This paper, based on medical literature and on proven facts, is going to tell the history of such a "war pestilence", a "contagious typhus".
Autochthonous epidemic typhus associated with Bartonella quintana bacteremia in a homeless person.
Badiaga, Sékéné; Brouqui, Philippe; Raoult, Didier
2005-05-01
Trench fever, a louse-borne disease caused by Bartonella quintana, is reemerging in homeless persons. Epidemic typhus is another life-threatening louse-borne disease caused by Rickettsia prowazekii and known to occur in conditions of war, famine, refugee camps, cold weather, poverty, or lapses in public health. We report the first case of seroconversion to R. prowazekii in a homeless person of Marseilles, France. This was associated with B. quintana bacteremia. Although no outbreaks of typhus have been notified yet in the homeless population, this disease is likely to reemerge in such situation.
The Effects of Elevated CO2 on a Subtropical Scrub Oak-Palmetto Plant Community
NASA Technical Reports Server (NTRS)
Vieglais, David; Hinkle, C. Ross; Drake, Bert
1995-01-01
A 2.5 year (1992-1995) pilot study was conducted on the effects of twice ambient CO2 on native scrub oak-palmetto vegetation at Kennedy Space Center (KSC). The effects suggest that rising atmospheric CO2 will increase terrestrial carbon and alter the distribution of carbon among the different pools of carbon.
Amin, Nuhu; Pickering, Amy J.; Ram, Pavani K.; Unicomb, Leanne; Najnin, Nusrat; Homaira, Nusrat; Ashraf, Sania; Abedin, Jaynal; Islam, M. Sirajul; Luby, Stephen P.
2014-01-01
We conducted a randomized, non-inferiority field trial in urban Dhaka, Bangladesh among mothers to compare microbial efficacy of soapy water (30 g powdered detergent in 1.5 L water) with bar soap and water alone. Fieldworkers collected hand rinse samples before and after the following washing regimens: scrubbing with soapy water for 15 and 30 seconds; scrubbing with bar soap for 15 and 30 seconds; and scrubbing with water alone for 15 seconds. Soapy water and bar soap removed thermotolerant coliforms similarly after washing for 15 seconds (mean log10 reduction = 0.7 colony-forming units [CFU], P < 0.001 for soapy water; mean log10 reduction = 0.6 CFU, P = 0.001 for bar soap). Increasing scrubbing time to 30 seconds did not improve removal (P > 0.05). Scrubbing hands with water alone also reduced thermotolerant coliforms (mean log10 reduction = 0.3 CFU, P = 0.046) but was less efficacious than scrubbing hands with soapy water. Soapy water is an inexpensive and microbiologically effective cleansing agent to improve handwashing among households with vulnerable children. PMID:24914003
Nishimura, Chieko
2006-01-01
Scrubbing of the hands and forearms with a brush and antiseptic agents has been the standard for surgical practice. However, it has been increasingly recognized that brush scrubbing may provoke side effects and that an alcohol-based hand antiseptic used in conjunction with a scrub agent enhances the effectiveness. In this study, two types of alcohol-based agents were used after a povidone-iodine (PVP-I) scrub and compared for their effectiveness. The study was conducted as a crossover trial with 20 volunteers. After hand rubbing with PVP-I, either PVP-I-ethanol rubbing or chlorhexidine gluconate-ethanol (CHG-ethanol) rubbing was used for surgical hand cleansing. Samples were collected by the modified glove juice method to count bacteria on hands. In both groups, the bacterial count was significantly reduced after handwashing (p < 0.001), and the reduction was still significant after 2 h (p < 0.001 for PVP-I-ethanol and p < 0.002 for CHG-ethanol). The log(10) reduction factor (RF) in the PVP-I-ethanol group was significantly higher than that in the CHG-ethanol group immediately after handwashing (p < 0.001) but significantly lowered after 2 h (p < 0.01) to the level similar to that of CHG-ethanol. Although RF was lower in the CHG-ethanol group immediately after and 2 h after handwashing compared to the PVP-I-ethanol group, it did not decrease with time. Brushless surgical scrubbing with PVP-I-ethanol or CHG-ethanol in conjunction with PVP-I showed antiseptic effects immediately after and 2 h after handwashing. RF immediately after handwashing was significantly higher with PVP-I-ethanol compared to CHG-ethanol, but it was similar in both groups after 2 h. These results suggest that when used in combination with a PVP-I scrub, an alcohol-based hand antiseptic containing the same active agent (PVP-I in this study) has a powerful antiseptic effect; however, when it contains different antiseptic agents (i.e. CHG in this study), it should be selected carefully based on its antiseptic property.
Raoult, D; Birtles, R J; Montoya, M; Perez, E; Tissot-Dupont, H; Roux, V; Guerra, H
1999-08-01
Typhus and other louse-transmitted bacterial infections in Peruvian sierra communities are known to occur but have not recently been assessed. In this study, 194 of 1,280 inhabitants of four villages in Calca Province in the Urubamba Valley were included. Thirty-nine (20%) of the 194 volunteers had antibodies to Rickettsia prowazekii, whereas 24 (12%) had antibodies to Bartonella quintana and 2 against Borrelia recurrentis. There was a significant correlation between the presence of infesting ectoparasites and antibodies to R. prowazekii, as well as between antibodies to R. prowazekii and ectoparasite infestation and fever in the previous 6 months. The proportion of inhabitants infested with ectoparasites was significantly higher in the highest-altitude village than in the other three villages. Two volunteers' antibody levels suggested a recent typhus infection, but only B. quintana DNA was amplified from lice. Epidemic typhus remains extant in the area, and B. quintana infections were encountered and documented for the first time in South America.
Bechah, Yassina; Capo, Christian; Mege, Jean-Louis; Raoult, Didier
2008-07-01
Epidemic typhus is transmitted to human beings by the body louse Pediculus humanus corporis. The disease is still considered a major threat by public-health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Until recently, Rickettsia prowazekii, the causal agent, was thought to be confined to human beings and their body lice. Since 1975, R prowazekii infection in human beings has been related to contact with the flying squirrel Glaucomys volans in the USA. Moreover, Brill-Zinsser disease, a relapsed form of epidemic typhus that appears as sporadic cases many years after the initial infection, is unrelated to louse infestation. Stress or a waning immune system are likely to reactivate this earlier persistent infection, which could be the source of new epidemics when conditions facilitate louse infestation. Finally, R prowazekii is a potential category B bioterrorism agent, because it is stable in dried louse faeces and can be transmitted through aerosols. An increased understanding of the pathogenesis of epidemic typhus may be useful for protection against this bacterial threat.
Use of Avagard in pediatric urologic procedures.
Palmer, Jeffrey S
2006-09-01
To evaluate the use of Avagard compared with a hand-brush scrub preparation by the urologist in preparation for inpatient and outpatient pediatric urologic operations. Avagard (chlorhexidine gluconate 1% solution and ethyl alcohol 61% wt/wt) is a waterless, brushless, and scrubless hand antiseptic indicated as a replacement for traditional preoperative brush hand scrubbing. We evaluated the first 550 patients for whom we used Avagard as a preoperative hand antiseptic and compared them with the last 550 consecutive patients for whom we performed traditional antiseptic-impregnated hand-brush scrubbing. All patients underwent pediatric urologic procedures. Patients were monitored postoperatively for signs of wound infection, and patients and the surgeon were monitored for side effects. A cost analysis was performed to compare the use of Avagard as a preoperative hand preparation with that of an antiseptic-impregnated hand-brush. The incidence of wound infection was one in the Avagard group and two in the hand-scrub group, not a statistically significant difference. All wound infections were successfully treated with a single course of oral antibiotics without any long-term sequelae. No side effects for the patients or surgeon were noted, including skin irritations or allergic reactions in either group. The use of Avagard was more time efficient and cost effective. To our knowledge, this is the first study demonstrating that Avagard is a fast, effective, easy to apply, and safe surgical hand preparation for pediatric urologic surgery. Its use is cost effective, as well as time efficient, in relation to the traditional surgical scrub.
Camer, Gerry Amor; Alejandria, Marissa; Amor, Miguel; Satoh, Hiroshi; Muramatsu, Yasukazu; Ueno, Hiroshi; Morita, Chiharu
2003-02-01
A total of 157 sera from febrile patients in the Philippine General Hospital in Manila, Luzon, and the Northern Samar Provincial Hospital, the Philippines, were used. Serum antibodies against spotted fever group Rickettsia (SFGR) and typhus group Rickettsia (TGR) were detected by indirect immunofluorescence test. Antibody positive rates were 1.3% for SFGR (Rickettsia japonica) and 2.5% for TGR (R. typhus), respectively. Rickettsial antibodies in humans in the Philippines were found for the first time. These results underscore the need for further epidemiological study of clinical rickettsioses in the Philippines.
Ferrer, Miriam M.; Good-Avila, Sara V.; Montaña, Carlos; Domínguez, César A.; Eguiarte, Luis E.
2009-01-01
Background and Aims Selection may favour a partial or complete loss of self-incompatibility (SI) if it increases the reproductive output of individuals in the presence of low mate availability. The reproductive output of individuals varying in their strength of SI may also be affected by population density via its affect on the spatial structuring and number of S-alleles in populations. Modifiers increasing levels of self-compatibility can be selected when self-compatible individuals receive reproductive compensation by, for example, increasing seed set and/or when they become associated with high fitness genotypes. Methods The effect of variation in the strength of SI and scrub density (low versus high) on seed set, seed germination and inbreeding depression in seed germination (δgerm) was investigated in the partially self-incompatible species Flourensia cernua by analysing data from self-, cross- and open-pollinated florets. Key Results Examination of 100 plants in both high and low scrub densities revealed that 51% of plants were strongly self-incompatible and 49 % varied from being self-incompatible to self-compatible. Seed set after hand cross-pollination was higher than after open-pollination for self-incompatible, partially self-incompatible and self-compatible plants but was uniformly low for strongly self-incompatible plants. Strongly self-incompatible and self-incompatible plants exhibited lower seed set, seed germination and multiplicative female fitness (floral display × seed set × seed germination) in open-pollinated florets compared with partially self-incompatible and self-compatible plants. Scrub density also had an effect on seed set and inbreeding depression: in low-density scrubs seed set was higher after open-pollination and δgerm was lower. Conclusions These data suggest that (a) plants suffered outcross pollen limitation, (b) female fitness in partially self-incompatible and self-compatible plants is enhanced by increased mate-compatibility and (c) plants in low-density scrubs received higher quality pollen via open-pollination than plants in high-density scrubs. PMID:19218580
Bulldozer better than poisons for preparing scrub oak planting sites
W. E. McQuilkin
1951-01-01
Before scrub oak lands can be reforested, some cheap and effective way of preparing planting sites must be found. Chemical weed killers have been tried, but they proved to be impractical for general use (see Northeastern Research Note 6).
DSP Synthesis Algorithm for Generating Florida Scrub Jay Calls
NASA Technical Reports Server (NTRS)
Lane, John; Pittman, Tyler
2017-01-01
A prototype digital signal processing (DSP) algorithm has been developed to approximate Florida scrub jay calls. The Florida scrub jay (Aphelocoma coerulescens), believed to have been in existence for 2 million years, living only in Florida, has a complicated social system that is evident by examining the spectrograms of its calls. Audio data was acquired at the Helen and Allan Cruickshank Sanctuary, Rockledge, Florida during the 2016 mating season using three digital recorders sampling at 44.1 kHz. The synthesis algorithm is a first step at developing a robust identification and call analysis algorithm. Since the Florida scrub jay is severely threatened by loss of habitat, it is important to develop effective methods to monitor their threatened population using autonomous means.
Spacecraft surgical scrub system
NASA Technical Reports Server (NTRS)
Abbate, M.
1980-01-01
Ease of handling and control in zero gravity and minimizing the quantity of water required were prime considerations. The program tasks include the selection of biocidal agent from among the variety used for surgical scrub, formulation of a dispensing system, test, and delivery of flight dispensers. The choice of an iodophore was based on effectiveness on single applications, general familiarity among surgeons, and previous qualification for space use. The delivery system was a choice between the squeeze foamer system and impregnated polyurethane foam pads. The impregnated foam pad was recommended because it is a simpler system since the squeeze foamer requires some applicator to effectively clean the skin surfaces, whereas the form pad is the applicator and agent combined. Testing demonstrated that both systems are effective for use as surgical scrubs.
Flying Squirrel–associated Typhus, United States
Krebs, John W.; Comer, James A.; Sumner, John W.; Rushton, Thomas C.; Lopez, Carlos E.; Nicholson, William L.; Rooney, Jane A.; Lance-Parker, Susan E.; McQuiston, Jennifer H.; Paddock, Christopher D.; Childs, James E.
2003-01-01
In March 2002, typhus fever was diagnosed in two patients residing in West Virginia and Georgia. Both patients were hospitalized with severe febrile illnesses, and both had been recently exposed to or had physical contact with flying squirrels or flying squirrel nests. Laboratory results indicated Rickettsia prowazekii infection. PMID:14609478
NASA Technical Reports Server (NTRS)
Schmalzer, Paul A.; Hinkle, C. Ross
1987-01-01
Four stands of oak scrub two, four, eight, and 25 years since fire were sampled with permanent 15 m line transects. Percent cover by species was determined. Plant samples were analyzed for a variety of substances. Transects were resurveyed in 1985 for vegetation parameters. Nutrient pools in biomass were calculated from biomass data and tissue nutrient concentrations. Soil nutrient pools were calculated from nutrient concentrations and bulk density. Species distribution and soil chemical properties were found to be closely related to water table depth. The following fire-related conclusions are reached: (1) major structural changes occur in scrub after fire in that shrub height is reduced and requires four to six years to exceed 1 m; (2) reduction in shrub height affects the suitability of scrub for the Florida scrub jay (3) live biomass increases with time since fire; (4) nutrient concentrations in live biomass do not change with time since fire; (5) species composition and richness are little changed after fire; and (6) imposition of a continued regime of burning on a three-year cycle may have adverse impacts not indicated by the recovery of scrub from a single fire.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bucknor, M.; Farmer, M.; Grabaskas, D.
The U.S. Nuclear Regulatory Commission has stated that mechanistic source term (MST) calculations are expected to be required as part of the advanced reactor licensing process. A recent study by Argonne National Laboratory has concluded that fission product scrubbing in sodium pools is an important aspect of an MST calculation for a sodium-cooled fast reactor (SFR). To model the phenomena associated with sodium pool scrubbing, a computational tool, developed as part of the Integral Fast Reactor (IFR) program, was utilized in an MST trial calculation. This tool was developed by applying classical theories of aerosol scrubbing to the decontamination ofmore » gases produced as a result of postulated fuel pin failures during an SFR accident scenario. The model currently considers aerosol capture by Brownian diffusion, inertial deposition, and gravitational sedimentation. The effects of sodium vapour condensation on aerosol scrubbing are also treated. This paper provides details of the individual scrubbing mechanisms utilized in the IFR code as well as results from a trial mechanistic source term assessment led by Argonne National Laboratory in 2016.« less
Nadchatram, M
2006-06-01
Some 2,000 species of mites of the family Trombiculidae are known in the world. The 6-legged larvae are mostly ectoparasites of reptiles, birds, mammals and invertebrates. Their 8-legged active nymphs and adults are free-living predators. In the Asia-Pacific region, a few species in various genera are vectors of scrub typhus and scrub-itch. In this a paper, a very bizarre trombiculid species, Vatacarus ipoides Southcott 1957, endoparasitic in the trachea of the amphibious sea snake, Laticauda colubrina (Schenider) is re-described based mostly on new-born larvae reared in the laboratory. Life history study of the mite produced very novel and interesting results. A brief account of the life-cycle was presented at the first laboratory demonstration of the Malaysian Society of Parasitology and Tropical Medicine Meeting by Nadchatram and Audy (1965). The life history is illustrated and described here in greater detail. The active nymphal, and the akinetic teleiophane stages are bypassed, which is unusual in the life-cycle of the family Trombiculidae. Also, the larva is the only stage in the life-cycle that feeds. The sexes are predetermined in the larval neosomatic stage and give rise to small males and bigger females. Having obtained adults of the species, by rearing, it is deemed unnecessary for the original proposal by Southcott to erect a new family, Vatacaridae, because the adults share all the attributes of the family Trombiculidae. The male and female obtained through laboratory rearing are illustrated for the first time. Relationship of V. ipoides with Laticauda snakes show close host-specificity, in a group of acarines that are generally habitat-specific. Possible explanations for their association are discussed. The unusual morphology and the formation of new structures during an instar is of ontogenetic and evolutionary importance. The hypertrophic larvae are superficially vermiform, rather than typically acarine in shape. This, and other biological features, necessitated the proposal of new morphological terms, and they are discussed here.
NASA Technical Reports Server (NTRS)
Berg, Melanie; Poivey C.; Petrick, D.; Espinosa, D.; Lesea, Austin; LaBel, K. A.; Friendlich, M; Kim, H; Phan, A.
2008-01-01
We compare two scrubbing mitigation schemes for Xilinx FPGA devices. The design of the scrubbers is briefly discussed along with an examination of mitigation limitations. Proton and Heavy Ion data are then presented and analyzed.
FLY ASH RECYCLE IN DRY SCRUBBING
The paper describes the effects of fly ash recycle in dry scrubbing. (Previous workers have shown that the recycle of product solids improves the utilization of slaked lime--Ca(OH)2--for sulfur dioxide (SO2) removal by spray dryers with bag filters.) In laboratory-scale experimen...
A test procedure for evaluating surgical hand disinfection.
Babb, J R; Davies, J G; Ayliffe, G A
1991-06-01
A technique for assessing the immediate and prolonged efficacy of surgical scrubs and alcoholic hand rubs is described. A mean baseline count is obtained from all volunteers and logarithmic reductions in resident skin flora immediately after one or more applications, and after wearing gloves for 3 h, are measured. Loose-fitting surgical gloves are used for sampling resident flora. Preparations were applied using a standard technique for 2 min, apart from one test with 70% isopropanol (IPA) in which the application time was 30 s. Two studies are described, one of which compared four chlorhexidine scrubs, and the second 70% IPA, 7.5% povidone-iodine scrub, 2% triclosan cleanser and unmedicated bar soap. In spite of their constituent similarity, the four chlorhexidine scrubs varied considerably in efficacy and user acceptability. A 2 min application of 70% IPA was the most effective treatment, and gave log10 reductions of 1.65 for immediate and 1.58 for prolonged effect. This was marginally more effective than a 30 s application, but the difference was not significant. 'Hibiscrub' was the most effective aqueous formulation and gave reductions of 1.01 for immediate effect and 1.16 for prolonged effect. The test described could be used by reference centres and manufacturers to assess the efficacy of new and existing surgical hand disinfection formulations.
Diagnosis of Queensland tick typhus and African tick bite fever by PCR of lesion swabs.
Wang, Jin Mei; Hudson, Bernard J; Watts, Matthew R; Karagiannis, Tom; Fisher, Noel J; Anderson, Catherine; Roffey, Paul
2009-06-01
We report 3 cases of Queensland tick typhus (QTT) and 1 case of African tick bite fever in which the causative rickettsiae were detected by PCR of eschar and skin lesions in all cases. An oral mucosal lesion in 1 QTT case was also positive.
A Markov decision process for managing habitat for Florida scrub-jays
Johnson, Fred A.; Breininger, David R.; Duncan, Brean W.; Nichols, James D.; Runge, Michael C.; Williams, B. Ken
2011-01-01
Florida scrub-jays Aphelocoma coerulescens are listed as threatened under the Endangered Species Act due to loss and degradation of scrub habitat. This study concerned the development of an optimal strategy for the restoration and management of scrub habitat at Merritt Island National Wildlife Refuge, which contains one of the few remaining large populations of scrub-jays in Florida. There are documented differences in the reproductive and survival rates of scrubjays among discrete classes of scrub height (<120 cm or "short"; 120-170 cm or "optimal"; .170 cm or "tall"; and a combination of tall and optimal or "mixed"), and our objective was to calculate a state-dependent management strategy that would maximize the long-term growth rate of the resident scrub-jay population. We used aerial imagery with multistate Markov models to estimate annual transition probabilities among the four scrub-height classes under three possible management actions: scrub restoration (mechanical cutting followed by burning), a prescribed burn, or no intervention. A strategy prescribing the optimal management action for management units exhibiting different proportions of scrub-height classes was derived using dynamic programming. Scrub restoration was the optimal management action only in units dominated by mixed and tall scrub, and burning tended to be the optimal action for intermediate levels of short scrub. The optimal action was to do nothing when the amount of short scrub was greater than 30%, because short scrub mostly transitions to optimal height scrub (i.e., that state with the highest demographic success of scrub-jays) in the absence of intervention. Monte Carlo simulation of the optimal policy suggested that some form of management would be required every year. We note, however, that estimates of scrub-height transition probabilities were subject to several sources of uncertainty, and so we explored the management implications of alternative sets of transition probabilities. Generally, our analysis demonstrated the difficulty of managing for a species that requires midsuccessional habitat, and suggests that innovative management tools may be needed to help ensure the persistence of scrub-jays at Merritt Island National Wildlife Refuge. The development of a tailored monitoring program as a component of adaptive management could help reduce uncertainty about controlled and uncontrolled variation in transition probabilities of scrub-height and thus lead to improved decision making.
[The epidemic typhus of 1813/14 in the area of lower Franconia].
Vasold, Manfred
2004-01-01
When Napoleon left for Moscow, in June 1812, he marched at the head of a huge army, perhaps more than half a million men strong. Roughly one fifth of them survived and came back to Germany at the turn of 1812/13. The "Grande Armée" had been subject to open battles and guerilla warfare, but even more to the ravages of hunger and infectious disease - it was epidemic typhus that killed off the soldiers. On their way back to France, the soldiers carried that disease to some areas of Germany, esp. those along the Main river. In late winter of 1813 some parts of Franconia suffered terribly. The epidemic subsided in summer 1813 when the lice - typhus is a louse-born disease - were less and better under control. But again in the winter of 1813/14, after the battle of Leipzig (Oct. 1813), a murderous epidemic of typhus broke out and killed very many people in cities like Wurzburg, Aschaffenburg, and Mainz. Mortality rose to a high percentage. Some contemporary German doctors had a rough idea that the carrier of the disease must be in the clothes. According to very conservative estimates one out of ten Germans fell sick, and ten percent of the sick died of typhus, a quarter of a million out of 23 million people. German historiography normally does not mention this epidemic in history text-books, so this epidemic is rather unknown.
Nursing typhus victims in the Second World War, 1942-1944: a discussion paper.
Brooks, Jane
2014-07-01
This article explores the care British nurses provided to victims of typhus during the Second World War. Typhus is associated with poverty and overcrowding. During wars in the pre-antibiotic era, civilians were particularly susceptible to epidemics, which military governments feared would spread to their troops. This discussion paper draws on archival data from three typhus epidemics in the Second World War to examine the expert work of British nurses in caring for victims during these potential public health disasters. The published sources for the paper include material from nursing and medical journals published between 1940-1947. Archival sources come from the National Archives in Kew, the Wellcome Library and the Army Medical Services Museum, between 1943-1945. Of particular interest is the correspondence with Dame Katharine Jones from nurses on active service overseas. Whilst epidemics of typhus are now rare, nurses in the present day may be required to care for the public in environments of extreme poverty and overcrowding, where life-threatening infectious diseases are prevalent. This article has demonstrated that it is possible for expert and compassionate nursing to alleviate suffering and prevent death, even when medical technologies are unavailable. Expert and compassionate care, adequate nutrition and hydration and attention to hygiene needs are crucial when there are limited pharmacological treatments and medical technologies available to treat infectious diseases. The appreciation of this could have implications for nurses working in current global conflicts. © 2013 John Wiley & Sons Ltd.
Joardar, Vinita; Williams, Kelly P.; Driscoll, Timothy; Hostetler, Jessica B.; Nordberg, Eric; Shukla, Maulik; Walenz, Brian; Hill, Catherine A.; Nene, Vishvanath M.; Azad, Abdu F.; Sobral, Bruno W.; Caler, Elisabet
2012-01-01
We present the draft genome for the Rickettsia endosymbiont of Ixodes scapularis (REIS), a symbiont of the deer tick vector of Lyme disease in North America. Among Rickettsia species (Alphaproteobacteria: Rickettsiales), REIS has the largest genome sequenced to date (>2 Mb) and contains 2,309 genes across the chromosome and four plasmids (pREIS1 to pREIS4). The most remarkable finding within the REIS genome is the extraordinary proliferation of mobile genetic elements (MGEs), which contributes to a limited synteny with other Rickettsia genomes. In particular, an integrative conjugative element named RAGE (for Rickettsiales amplified genetic element), previously identified in scrub typhus rickettsiae (Orientia tsutsugamushi) genomes, is present on both the REIS chromosome and plasmids. Unlike the pseudogene-laden RAGEs of O. tsutsugamushi, REIS encodes nine conserved RAGEs that include F-like type IV secretion systems similar to that of the tra genes encoded in the Rickettsia bellii and R. massiliae genomes. An unparalleled abundance of encoded transposases (>650) relative to genome size, together with the RAGEs and other MGEs, comprise ∼35% of the total genome, making REIS one of the most plastic and repetitive bacterial genomes sequenced to date. We present evidence that conserved rickettsial genes associated with an intracellular lifestyle were acquired via MGEs, especially the RAGE, through a continuum of genomic invasions. Robust phylogeny estimation suggests REIS is ancestral to the virulent spotted fever group of rickettsiae. As REIS is not known to invade vertebrate cells and has no known pathogenic effects on I. scapularis, its genome sequence provides insight on the origin of mechanisms of rickettsial pathogenicity. PMID:22056929
Rentas, Francisco; Harman, Ronald; Gomez, Charlotte; Salata, Jeanne; Childs, Joseph; Silva, Tonya; Lippert, Lloyd; Montgomery, Joshua; Richards, Allen; Chan, Chye; Jiang, Ju; Reddy, Heather; Li, John; Goodrich, Raymond
2007-02-01
Treatment of blood products with riboflavin and light has been used to reduce the number of certain pathogens. Orientia (formerly Rickettsia) tsutsugamushi, the scrub typhus agent, is an obligate intracellular bacterium that grows free in the cytoplasm of infected cells. This study evaluated the capability of riboflavin and light to inactivate O. tsutsugamushi in red blood cells (RBCs), platelets (PLTs), and plasma, as measured by mouse infectivity. A total of 108 mice, equally divided into groups receiving RBCs, plasma, and PLTs, received untreated products infected with 10(0) to 10(5) organisms. Eighteen mice received products infected with 10(5) organisms and were subsequently treated with riboflavin and light. Mice were monitored daily for up to 17 days for signs and symptoms of infection (e.g., lethargy, labored breathing, rough coat) and killed upon appearance of symptoms or on Day 17 after infection. Real-time polymerase chain reaction (PCR) on blood and Giemsa stains from peritoneal exudates were performed. A total of 102 of 108 mice receiving the untreated products developed signs and symptoms of infection and had positive PCR and Giemsa stain results. None of the 18 animals receiving riboflavin and light-treated blood products exhibited signs or symptoms of infection, nor was infection observed by PCR testing or Giemsa staining. Riboflavin and light are effective in reducing O. tsutsugamushi. Mice injected with blood products inoculated with 10(5) organisms and treated with riboflavin and light did not experience any signs or symptoms of infection, 17 days after inoculation. A 5-log reduction of this organism in blood was achieved as assayed in an animal model.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-24
...] Endangered and Threatened Wildlife and Plants; Incidental Take Permit Application; Proposed Low-Effect... (Aphelocoma coerulescens) (scrub-jay) breeding, feeding, and sheltering habitat incidental to lot preparation... taking approximately 0.23 acre (0.1 hectares (ha)) of Florida scrub-jay breeding, feeding, and sheltering...
Newly Recognized Pediatric Cases of Typhus Group Rickettsiosis, Houston, Texas, USA
Erickson, Timothy; da Silva, Juliana; Nolan, Melissa S.; Marquez, Lucila; Munoz, Flor M.
2017-01-01
An increase in typhus group rickettsiosis and an expanding geographic range occurred in Texas, USA, over a decade. Because this illness commonly affects children, we retrospectively examined medical records from 2008–2016 at a large Houston-area pediatric hospital and identified 36 cases. The earliest known cases were diagnosed in 2011. PMID:29148369
[Typhus in Mexico City in 1915].
Rodríguez, Martha Eugenia
2016-01-01
The year 1915 was particularly difficult; it was characterized by droughts, famines, and outbreaks of diseases including typhus.This text exposes its spread in Mexico City as well as the measures implemented to combat it, carried out before knowing the etiology of the illness, focused on cleaning up the environment and the measures undertaken afterwards with the aim of delousing people.
Medical Surveillance Monthly Report (MSMR). Volume 2, Number 11, November 2015
2015-11-01
encounters within 2 weeks Typhoid fever 002.0 once per 360 days 1 inpatient Typhus fever 080, 081.x once per lifetime 1 inpatient, 2 outpatient encounters...Tuberculosis 49 18 36.7 3 1 33.3 NR NR NR NR NR NR Tularemia 2 1 50.0 0 0 * 1 1 100.0 0 0 * Typhoid fever 4 0 0.0 0 0 * NR NR NR NR NR NR Typhus fever 2 1 50.0 0...Tularemia 1 1 100.0 0 0 * 1 1 100.0 0 0 * Typhoid fever 3 0 0.0 0 0 * NR NR NR NR NR NR Typhus fever 2 0 0.0 0 0 * 0 0 * 0 0 * Vaccine, adverse event 1
Development and implementation of a scrub habitat compensation plan for Kennedy Space Center
NASA Technical Reports Server (NTRS)
Schmalzer, Paul A.; Breininger, David R.; Adrian, Frederic W.; Schaub, Ron; Duncan, Brean W.
1994-01-01
Kennedy Space Center (KSC), located on Merritt Island on the east coast of central Florida, is one of three remaining major populations of the Florida Scrub Jay (Aphelocoma coerulescens coerulescens), listed as threatened by the U.S. Fish and Wildlife Service (USFWS) since 1987. Construction of new facilities by the National Aeronautics and Space Administration (NASA) on KSC over the next five years has the potential to impact up to 193 ac (78.1 ha) of Scrub Jay habitat. Under an early consultation process with the Endangered Species Office of the USFWS, NASA agreed to a compensation plan for loss of Scrub Jay habitat. The compensation plan required NASA to restore or create scrub on KSC at a 2:1 ratio for that lost. The compensation plan emphasized restoration of scrub habitat that is of marginal or declining suitability to Scrub Jays because it has remained unburned. Although prescribed burning has been conducted by the USFWS Merritt Island National Wildlife Refuge (MINWR) for more than ten years, significant areas of scrub remain unburned because they have been excluded from fire management units or because landscape fragmentation and a period of fire suppression allowed scrub to reach heights and diameters that are fire resistant. For such areas, mechanical cutting followed by prescribed burning was recommended for restoration. A second part of the restoration plan is an experimental study of scrub reestablishment (i.e., creation) on abandoned, well drained agricultural sites by planting scrub oaks and other scrub plants. The compensation plan identified 260 ac (105 ha) of scrub restoration in four areas and a 40 ac (16 ha) scrub creation site. Monitoring of restoration sites required under the plan included: establishing permanent vegetation sample transects before treatment and resampling annually for ten years after treatment, and color banding Scrub Jays to determine territories prior to treatment followed by monitoring reproductive success and survival for ten years after treatment. Monitoring scrub creation sites included determining survival of planted material for five years and establishing permanent transects to follow vegetation development for ten years after planting. Scrub Jay monitoring of creation sites is incorporated with that of adjacent restoration sites.
Scrubbing liquors for nitrogen tetroxide
NASA Technical Reports Server (NTRS)
Thomas, J. J.
1978-01-01
Once it was determined that the wet scrubbing concept was the most practical solution to the N2O4 emission problem, it became important to optimize the composition of the scrubbing liquor. Several reagents were cited in the literature as being advantageous in scrubbing NO2. Experiments were conducted on a model wet scrubber in order to verify and rank the performances of these scrubbing liquors. The most efficient scrubbing liquor found experimentally was a 10% sodium sulfite solution.
Liu, Yan; Wu, Bin; Weinstock, George; Walker, David H.; Yu, Xue-jie
2014-01-01
Louse borne typhus (also called epidemic typhus) was one of man's major scourges, and epidemics of the disease can be reignited when social, economic, or political systems are disrupted. The fear of a bioterrorist attack using the etiologic agent of typhus, Rickettsia prowazekii, was a reality. An attenuated typhus vaccine, R. prowazekii Madrid E strain, was observed to revert to virulence as demonstrated by isolation of the virulent revertant Evir strain from animals which were inoculated with Madrid E strain. The mechanism of the mutation in R. prowazekii that affects the virulence of the vaccine was not known. We sequenced the genome of the virulent revertant Evir strain and compared its genome sequence with the genome sequences of its parental strain, Madrid E. We found that only a single nucleotide in the entire genome was different between the vaccine strain Madrid E and its virulent revertant strain Evir. The mutation is a single nucleotide insertion in the methyltransferase gene (also known as PR028) in the vaccine strain that inactivated the gene. We also confirmed that the vaccine strain E did not cause fever in guinea pigs and the virulent revertant strain Evir caused fever in guinea pigs. We concluded that a single nucleotide insertion in the methyltransferase gene of R. prowazekii attenuated the R. prowazekii vaccine strain E. This suggested that an irreversible insertion or deletion mutation in the methyl transferase gene of R. prowazekii is required for Madrid E to be considered a safe vaccine. PMID:25412248
Liu, Yan; Wu, Bin; Weinstock, George; Walker, David H; Yu, Xue-Jie
2014-01-01
Louse borne typhus (also called epidemic typhus) was one of man's major scourges, and epidemics of the disease can be reignited when social, economic, or political systems are disrupted. The fear of a bioterrorist attack using the etiologic agent of typhus, Rickettsia prowazekii, was a reality. An attenuated typhus vaccine, R. prowazekii Madrid E strain, was observed to revert to virulence as demonstrated by isolation of the virulent revertant Evir strain from animals which were inoculated with Madrid E strain. The mechanism of the mutation in R. prowazekii that affects the virulence of the vaccine was not known. We sequenced the genome of the virulent revertant Evir strain and compared its genome sequence with the genome sequences of its parental strain, Madrid E. We found that only a single nucleotide in the entire genome was different between the vaccine strain Madrid E and its virulent revertant strain Evir. The mutation is a single nucleotide insertion in the methyltransferase gene (also known as PR028) in the vaccine strain that inactivated the gene. We also confirmed that the vaccine strain E did not cause fever in guinea pigs and the virulent revertant strain Evir caused fever in guinea pigs. We concluded that a single nucleotide insertion in the methyltransferase gene of R. prowazekii attenuated the R. prowazekii vaccine strain E. This suggested that an irreversible insertion or deletion mutation in the methyl transferase gene of R. prowazekii is required for Madrid E to be considered a safe vaccine.
Differences in Attentional Strategies by Novice and Experienced Operating Theatre Scrub Nurses
ERIC Educational Resources Information Center
Koh, Ranieri Y. I.; Park, Taezoon; Wickens, Christopher D.; Ong, Lay Teng; Chia, Soon Noi
2011-01-01
This study investigated the effect of nursing experience on attention allocation and task performance during surgery. The prevention of cases of retained foreign bodies after surgery typically depends on scrub nurses, who are responsible for performing multiple tasks that impose heavy demands on the nurses' cognitive resources. However, the…
Studies on Typhus and Spotted Fever
1979-02-01
thawing caused no detectaule loss of ricket - tsial infectivity. Accordingly, the longterm survival of typhus organisms at -700 C in these and other...or even qualitative,differentiation between a specific action on intracellular ricket - tsiae and selective cytotoxicity directed against infected...study of the cell envelopes of Rickettsia prowazekii, Rickettsia ricket ii, and Rickettsia tsutsugamushi. Infect. Immun. 21: 1020-1uZ3 (1978). 8
Seroepidemiology of spotted fever group and typhus group rickettsioses in humans, South Korea.
Jang, Won-Jong; Choi, Yeon-Joo; Kim, Jong-Hyun; Jung, Kwang-Don; Ryu, Ji-Sun; Lee, Seung-Hyun; Yoo, Cheon-Kwon; Paik, Hyung-Suk; Choi, Myung-Sik; Park, Kyung-Hee; Kim, Ik-Sang
2005-01-01
The prevalence of spotted fever group (SFG) and typhus group (TG) rickettsioses was investigated in 3,362 sera by immunofluorescence assay. The serum samples were obtained from patients with acute febrile episodes in South Korea from December 1992 to November 1993. The number of polyvalent positive sera against SFG rickettsial agents at the level of 1: 40 dilution was 269 (8%) in Rickettsia sibirica, 482 (14.34%) in R. conorii, and 546 (16.24%) in R. akari. Many of the positive sera contained immunoglobulin (Ig) M antibodies rather than IgG antibodies. These results strongly suggest that SFG rickettsioses are prevalent in Korea. For TG rickettsial agents, the number of positive sera was 1,096 (32.60%) in R. typhi and 951 (28.29%) in R. prowazekii. Only a few epidemic typhus positive sera contained IgM antibodies. The result suggests that recent and/or primary infections of epidemic typhus were very rare in Korea during the said period. Among seven patients who had high titers (1:5,120) of IgG antibody to R. prowazekii, six were over 50 years old. The result suggests that Brill-Zinsser disease was prevalent in Korea.
Habitat model for the Florida Scrub Jay on John F. Kennedy Space Center
NASA Technical Reports Server (NTRS)
Breininger, David R.
1992-01-01
The Florida Scrub Jay is endemic to Florida. The John F. Kennedy Space Center (KSC) provides habitat for one of the three largest populations of the Florida Scrub Jay. This threatened bird occupies scrub, slash pine flatwoods, disturbed scrub, and coastal strand on KSC. Densities of Florida Scrub Jays were shown to vary with habitat characteristics but not necessarily with vegetation type. Relationships between Florida Scrub Jay densities and habitat characteristics were used to develop a habitat model to provide a tool to compare alternative sites for new facilities and to quantify environmental impacts. This model is being tested using long term demographic studies of colorbanded Florida Scrub Jays. Optimal habitat predicted by the model has greater than or equal to 50 percent of the shrub canopy comprised of scrub oaks, 20-50 percent open space or scrub oak vegetation within 100 m of a ruderal edge, less than or equal to 15 percent pine canopy cover, a shrub height of 120-170 cm, and is greater than or equal to 100 m from a forest. This document reviews life history, social behavior, food, foraging habitat, cover requirements, characteristics of habitat on KSC, and habitat preferences of the Florida Scrub Jay. Construction of the model and its limitations are discussed.
Indian tick typhus presenting with gangrene: a case report from an urban slum of Delhi.
Kumar, Manish; Singh, Raghvendra; Yadav, Mukesh
2014-01-01
Indian Tick Typhus has been rarely reported in children from Delhi. A 10-y-old male child from Delhi presented with fever, non specific gastrointestinal symptoms, petechial rash and gangrene of all the toes. Possibility of rickettsial infection was entertained after the child failed to improve with best of the antibiotics. Sample for serology for rickettsial infection was sent and Doxycycline was started empirically. He became afebrile within 72 h of starting Doxycycline. Later, diagnosis of Indian Tick Typhus was confirmed on the basis of IgM positivity against Rickettsia conori. Possibility of rickettsial infection should be entertained in children with history of fever and skin rash, especially if the child fails to improve with a course of antibiotics and common infectious etiologies have been ruled out.
Jail fever (epidemic typhus) outbreak in Burundi.
Raoult, D; Roux, V; Ndihokubwayo, J B; Bise, G; Baudon, D; Marte, G; Birtles, R
1997-01-01
We recently investigated a suspected outbreak of epidemic typhus in a jail in Burundi. We tested sera of nine patients by microimmunofluorescence for antibodies to Rickettsia prowazekii and Rickettsia typhi. We also amplified and sequenced from lice gene portions specific for two R. prowazekii proteins: the gene encoding for citrate synthase and the gene encoding for the rickettsial outer membrane protein. All patients exhibited antibodies specific for R. prowazekii. Specific gene sequences were amplified in two lice from one patient. The patients had typical clinical manifestations, and two died. Molecular techniques provided a convenient and reliable means of examining lice and confirming this outbreak. The jail-associated outbreak predates an extensive ongoing outbreak of louse-borne typhus in central eastern Africa after civil war and in refugee camps in Rwanda, Burundi (1), and Zaire.
Jail fever (epidemic typhus) outbreak in Burundi.
Raoult, D.; Roux, V.; Ndihokubwayo, J. B.; Bise, G.; Baudon, D.; Marte, G.; Birtles, R.
1997-01-01
We recently investigated a suspected outbreak of epidemic typhus in a jail in Burundi. We tested sera of nine patients by microimmunofluorescence for antibodies to Rickettsia prowazekii and Rickettsia typhi. We also amplified and sequenced from lice gene portions specific for two R. prowazekii proteins: the gene encoding for citrate synthase and the gene encoding for the rickettsial outer membrane protein. All patients exhibited antibodies specific for R. prowazekii. Specific gene sequences were amplified in two lice from one patient. The patients had typical clinical manifestations, and two died. Molecular techniques provided a convenient and reliable means of examining lice and confirming this outbreak. The jail-associated outbreak predates an extensive ongoing outbreak of louse-borne typhus in central eastern Africa after civil war and in refugee camps in Rwanda, Burundi (1), and Zaire. PMID:9284381
CO2 study shows effects on scrub oak environment
NASA Technical Reports Server (NTRS)
2000-01-01
CO2 study site manager and plant physiologist Graham Hymus (left) examines scrub oak foliage while project engineer David Johnson (right) looks on. The life sciences study is showing that rising levels of carbon dioxide in our atmosphere, caused by the burning of fossil fuels, could spur plant growth globally. The site of KSC's study is a natural scrub oak area near the Vehicle Assembly Building. Twelve-foot areas of scrub oak have been enclosed in 16 open-top test chambers into which CO2 has been blown. Five scientists from NASA and the Smithsonian Environmental Research Center in Edgewater, Md., work at the site to monitor experiments and keep the site running. Scientists hope to continue the study another five to 10 years. More information on this study can be found in Release No. 57- 00.
One hospital's clinical evaluation of brushless scrubbing.
Berman, Mara
2004-02-01
BRUSHLESS SCRUBBING rapidly is becoming an accepted method for surgical hand scrubbing. AN EVALUATION was undertaken at an acute care hospital in the southeastern United States to examine brushless scrubbing before laminectomy, craniotomy, and colectomy procedures. PATIENTS DID NOT SHOW an increase in postoperative surgical site infections when the brushless scrubbing product was used. SATISFACTION AND COMPLIANCE among users of the product was positive.
Endangered and Threatened Species at Kennedy Space Center Merritt Island National Wildlife Refuge
NASA Technical Reports Server (NTRS)
Galdolfi, Catherine
2010-01-01
Throughout my internship, I assisted with the long-term monitoring of the Florida Scrub- Jay (Aphelocoma coerulescens), a threatened species endemic to Florida. The Florida Scrub Jay diet consists of insects and small vertebrates throughout most of the year; however, during the winter their primary diet is acorns because the insect population is low. Furthermore, the Florida Scrub-Jay is a habitat specialist that lives in a disappearing plant community called the scrub, which consists of sand live oak, myrtle oak and chapman oak. The Florida Scrub-Jay is considered threatened because its numbers are decreasing primarily due to the loss of habitat that it needs to survive. Scrub habitat is highly desirable for human development because it is high, dry, and sandy. Periodic controlled burns maintain the scrub in a low, open condition favored by Scrub-Jays. Florida Scrub-Jays build their nests approximately 3-5 feet (approximately 1.5 m) above the ground in shrubby oaks (Breininger 153), mate for life and are cooperative breeders; which means that the young jays remain in their natal territory for at least a year to help their parents defend their territory, feed the young, and mob predators. (Breininger 152). I assisted in conducting monthly censuses at long-term monitoring sites and a juvenile in July survey to determine reproductive success for the year. In addition, to Scrub-Jay monitoring, I also had the opportunity to assist with some long term monitoring of ecosystem recovery. Scrub is a fire maintained system. Fire maintains the structure of scrub necessary for many of the threatened species that reside in the scrub habitat.
Radiation-Tolerant Intelligent Memory Stack - RTIMS
NASA Technical Reports Server (NTRS)
Ng, Tak-kwong; Herath, Jeffrey A.
2011-01-01
This innovation provides reconfigurable circuitry and 2-Gb of error-corrected or 1-Gb of triple-redundant digital memory in a small package. RTIMS uses circuit stacking of heterogeneous components and radiation shielding technologies. A reprogrammable field-programmable gate array (FPGA), six synchronous dynamic random access memories, linear regulator, and the radiation mitigation circuits are stacked into a module of 42.7 42.7 13 mm. Triple module redundancy, current limiting, configuration scrubbing, and single- event function interrupt detection are employed to mitigate radiation effects. The novel self-scrubbing and single event functional interrupt (SEFI) detection allows a relatively soft FPGA to become radiation tolerant without external scrubbing and monitoring hardware
A century of typhus, lice and Rickettsia.
Andersson, J O; Andersson, S G
2000-03-01
At the beginning of the 20th century, it was discovered at the Pasteur Institute in Tunis that epidemic typhus is transmitted by the human body louse. The complete genome sequence of its causative agent, Rickettsia prowazekii, was determined at Uppsala University in Sweden at the end of the century. In this mini-review, we discuss insights gained from the genome sequence of this fascinating and deadly organism.
Effects of Forest Management Practices on Terrestrial Coleopteran Assemblages in Sand Pine Scrub
Cathryn H. Greenberg; Michael C. Thomas
1995-01-01
Coleopteran assemblages were sampled monthly for one year using pitfall traps in replicated sites of three 5- to 7-year-old disturbance treatments and mature forested sand pine scrub in the Ocala National Forest, Marion County, Florida. Disturbance treatments were (1) burning at high-intensity and salvage-logging; (2) clearcutting, roller-chopping and broadcast...
Fire alters patterns of genetic diversity among 3 lizard species in Florida Scrub habitat.
Schrey, Aaron W; Ashton, Kyle G; Heath, Stacy; McCoy, Earl D; Mushinsky, Henry R
2011-01-01
The Florida Sand Skink (Plestiodon reynoldsi), the Florida Scrub Lizard (Sceloporus woodi), and the Six-lined Racerunner (Aspidoscelis sexlineata) occur in the threatened and fire-maintained Florida scrub habitat. Fire may have different consequences to local genetic diversity of these species because they each have different microhabitat preference. We collected tissue samples of each species from 3 sites with different time-since-fire: Florida Sand Skink n = 73, Florida Scrub Lizard n = 70, and Six-lined Racerunner n = 66. We compared the effect of fire on genetic diversity at microsatellite loci for each species. We screened 8 loci for the Florida Sand Skink, 6 loci for the Florida Scrub Lizard, and 6 loci for the Six-lined Racerunner. We also tested 2 potential driving mechanisms for the observed change in genetic diversity, a metapopulation source/sink model and a local demographic model. Genetic diversity varied with fire history, and significant genetic differentiation occurred among sites. The Florida Scrub Lizard had highest genetic variation at more recently burned sites, whereas the Florida Sand Skink and the Six-lined Racerunner had highest genetic variation at less recently burned sites. Habitat preferences of the Florida Sand Skink and the Florida Scrub Lizard may explain their discordant results, and the Six-lined Racerunner may have a more complicated genetic response to fire or is acted on at a different geographic scale than we have investigated. Our results indicate that these species may respond to fire in a more complicated manner than predicted by our metapopulation model or local demographic model. Our results show that the population-level responses in genetic diversity to fire are species-specific mandating conservation management of habitat diversity through a mosaic of burn frequencies.
Is it time for brushless scrubbing with an alcohol-based agent?
Gruendemann, B J; Bjerke, N B
2001-12-01
The practice of surgical scrubbing in perioperative settings is changing rapidly. This article presents information about eliminating the traditional scrub brush technique and using an alcohol formulation for surgical hand scrubs. Also covered are antimicrobial agents, relevant US Food and Drug Administration classifications, skin and fingernail care, and implementation of changes. The article challenges surgical team members to evaluate a new and different approach to surgical hand scrubbing.
Plant communities of Santa Rosa Island, Channel Islands National Park
Clark, Ronilee A.; Halvorson, William L.; Sawdo, Andell A.; Danielsen, Karen C.
1990-01-01
A survey of the plant communities on Santa Rosa Island, Channel Islands National Park, was conducted from January through July 1988. Vegetation data were collected at 296 sites using a releve technique. The plant communities described include: grassland, coastal marsh, caliche scrub, coastal sage scrub, lupine scrub, baccharis scrub, coastal bluff scrub, coastal dune scrub, mixed chaparral, mixed woodland, torrey pine woodland, closed-cone pine woodland, island oak woodland, riparian woodland, and riparian herbaceous vegetation. The areal extent of each community was mapper on USGS 7.5' topographic maps, and digitized for GIS manipulation.
2009-02-27
CAPE CANAVERAL, Fla. – Close-up of a Florida scrub jay in the woods near NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky
2009-02-27
CAPE CANAVERAL, Fla. – Florida scrub jays scan their territory from a bush at NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky
2009-02-27
CAPE CANAVERAL, Fla. – Florida scrub jays scan their territory from a bush at NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky
2009-02-27
CAPE CANAVERAL, Fla. – A Florida scrub jay perches on a branch in a wooded area at NASA's Kennedy Space Center in Florida. As the name implies, the Florida scrub jay thrives in a scrub, which is an extremely dry habitat. Their ideal environment is a relatively open flatwoods of oak or sand pine scrub with trees less than 10 feet tall, wide apart and providing minimal canopy cover. The last recorded population count of Florida scrub jays is just a little over 2,000, mostly located at Kennedy but also in some scattered scrubs all over central and southern Florida. Photo credit: NASA/Ben Smegelsky
Dzul-Rosado, Karla R; Zavala Velázquez, Jorge Ernesto; Zavala-Castro, Jorge
2012-01-01
Rickettsia typhi: is an intracellular bacteria who causes murine typhus. His importance is reflected in the high frequency founding specific antibodies against Rickettsia typhi in several worldwide seroepidemiological studies, the seroprevalence ranging between 3-36%. Natural reservoirs of R. typhi are rats (some species belonging the Rattus Genus) and fleas (Xenopsylla cheopis) are his vector. This infection is associated with overcrowding, pollution and poor hygiene. Typically presents fever, headache, rash on trunk and extremities, in some cases may occur organ-specific complications, affecting liver, kidney, lung or brain. Initially the disease is very similar to other diseases, is very common to confuse the murine typhus with Dengue fever, therefore, ignorance of the disease is a factor related to complications or non-specific treatments for the resolution of this infection. This paper presents the most relevant information to consider about the rickettsiosis caused by Rickettsia typhi. PMID:24893060
Cluster of Sylvatic Epidemic Typhus Cases Associated with Flying Squirrels, 2004–2006
Chapman, Alice S.; Swerdlow, David L.; Dato, Virginia M.; Anderson, Alicia D.; Moodie, Claire E.; Marriott, Chandra; Amman, Brian; Hennessey, Morgan; Fox, Perry; Green, Douglas B.; Pegg, Eric; Nicholson, William L.; Eremeeva, Marina E.
2009-01-01
In February 2006, a diagnosis of sylvatic epidemic typhus in a counselor at a wilderness camp in Pennsylvania prompted a retrospective investigation. From January 2004 through January 2006, 3 more cases were identified. All had been counselors at the camp and had experienced febrile illness with myalgia, chills, and sweats; 2 had been hospitalized. All patients had slept in the same cabin and reported having seen and heard flying squirrels inside the wall adjacent to their bed. Serum from each patient had evidence of infection with Rickettsia prowazekii. Analysis of blood and tissue from 14 southern flying squirrels trapped in the woodlands around the cabin indicated that 71% were infected with R. prowazekii. Education and control measures to exclude flying squirrels from housing are essential to reduce the likelihood of sylvatic epidemic typhus. PMID:19624912
Cluster of sylvatic epidemic typhus cases associated with flying squirrels, 2004-2006.
Chapman, Alice S; Swerdlow, David L; Dato, Virginia M; Anderson, Alicia D; Moodie, Claire E; Marriott, Chandra; Amman, Brian; Hennessey, Morgan; Fox, Perry; Green, Douglas B; Pegg, Eric; Nicholson, William L; Eremeeva, Marina E; Dasch, Gregory A
2009-07-01
In February 2006, a diagnosis of sylvatic epidemic typhus in a counselor at a wilderness camp in Pennsylvania prompted a retrospective investigation. From January 2004 through January 2006, 3 more cases were identified. All had been counselors at the camp and had experienced febrile illness with myalgia, chills, and sweats; 2 had been hospitalized. All patients had slept in the same cabin and reported having seen and heard flying squirrels inside the wall adjacent to their bed. Serum from each patient had evidence of infection with Rickettsia prowazekii. Analysis of blood and tissue from 14 southern flying squirrels trapped in the woodlands around the cabin indicated that 71% were infected with R. prowazekii. Education and control measures to exclude flying squirrels from housing are essential to reduce the likelihood of sylvatic epidemic typhus.
Hobson, D W; Woller, W; Anderson, L; Guthery, E
1998-10-01
Since the introduction in the 1970s of surgical hand scrub formulations that contain 4% chlorhexidine gluconate (CHG), new surgical scrub formulations that have improved efficacy, persistence, or significantly improved use characteristics have not been forthcoming. In addition, the manufacturer's labeling for popular hand scrub products generally requires scrub times in excess of 6 minutes, whereas current practical needs call for products with substantially shorter scrub times. A new alcohol-based surgical scrub formulation, which has ingredients that provide emollient, surfactant, and antimicrobial persistence characteristics to complement the rapid and broad-spectrum antiseptic qualities of alcohol, has been developed in an effort to address these current practical needs. The relative efficacy of a new alcohol-based surgical scrub formulation that contains ingredients that provide surfactant and antimicrobial persistence characteristics was compared with that of commercial 4% CHG and 7.5% povidone iodine (PVPI) formulations with use of human subjects. Hand antimicrobial count sampling was performed by using standardized "glove juice" methodology. The efficacy and persistence results of the new formulation showed statistically significant improvement over both CHG and PVPI at a substantially lessened scrub time (3 minutes). In addition, use of the new formulation without a scrub brush produced results statistically similar to 3-minute applications with either a brush or a sponge. The new alcohol-based formulation demonstrates promise as a new surgical hand scrub formulation with antimicrobial and use characteristics that are significantly improved over current CHG and PVPI formulations. These studies demonstrate the suitability of this formulation for use as a surgical hand scrub and for brushless application.
Bechah, Yassina; Capo, Christian; Grau, Georges E; Raoult, Didier; Mege, Jean-Louis
2007-06-01
Epidemic typhus remains a major disease threat, furthermore, its etiologic agent, Rickettsia prowazekii, is classified as a bioterrorism agent. We describe here a murine model of epidemic typhus that reproduced some features of the human disease. When BALB/c mice were inoculated intravenously with R. prowazekii (Breinl strain), they survived but did not clear R. prowazekii infection. Immunohistological analysis of tissues and quantitative PCR showed that R. prowazekii was present in blood, liver, lungs and brain 1 day after infection and persisted for at least 9 days. Importantly, infected mice developed interstitial pneumonia, with consolidation of the alveoli, hemorrhages in lungs, multifocal granulomas in liver, and hemorrhages in brain, as seen in humans. Circulating antibodies directed against R. prowazekii were detected at day 4 post-infection and steadily increased for up to 21 days, demonstrating that R. prowazekii lesions were independent of humoral immune response. R. prowazekii-induced lesions were associated with inflammatory response, as demonstrated by elevated levels of inflammatory cytokines including interferon-gamma, tumor necrosis factor and the CC chemokine RANTES in the lesions. We concluded that the BALB/c mouse strain provides a useful model for studying the pathogenic mechanisms of epidemic typhus and its control by the immune system.
Rickettsioses in Japan and the far East.
Mahara, Fumihiko
2006-10-01
Three rickettsial diseases are known to exist in Japan currently: Japanese spotted fever (JSF), Tsutsugamushi disease (TD; scrub typhus), and Q fever. Since April 1999, the system for infection control and prevention in Japan has changed drastically. JSF, Q fever, and TD, as emerging infectious diseases, are designated as national notifiable diseases.The geographic distribution of JSF patients is along the coast of central and southwestern Japan, whereas TD and Q fever occur almost all over the country. The number of JSF patients reported was 216 cases during 1984-1998 and 268 cases, under the revised law, in 1999-2004. About 300-1000 cases of TD occur every year, and 7-46 cases of Q fever in 1999-2004. The number of cases of JSF and its endemic area are gradually increasing. There was only one fatality due to JSF until 2003, whereas two patients died of JSF in 2004, so JSF is still a life-threatening disease in Japan. Treatment of fulminant JSF consists of prompt administration of a combination of tetracycline and quinolone. Recent tick surveys revealed that the most probable vectors of JSF are Haemophysalis flava and Haemophysalis hystericis. In addition to R. japonica, two serotypes or species of spotted fever group rickettsiae have been isolated from ticks in Japan; one is closely related to R. helvetica and the other is a new genotype of unknown genotype AT, which is closely related to a Slovakian genotype. These serotypes are of uncertain clinical significance. Epidemiology of rickettsioses in the Far East is mentioned briefly.
Robert D. Cox; Edith B. Allen
2008-01-01
Restoration of semi-arid shrub ecosystems often requires control of invasive grasses but the effects of these grass-control treatments on native and exotic forbs have not been investigated adequately to assess long-term stability. In southern California, coastal sage scrub (CSS) vegetation is one semi-arid shrub community that has been invaded extensively by both...
A Stand-Replacement Prescribed Burn in Sand Pine Scrub
Kenneth W. Outcalt; Cathryn H. Greenberg
1998-01-01
This paper describes fire characteristics and the immediate effects of a prescribed, high-intensity bum on a 12.2 hectare portion of a stand of Ocala sand pine scrub. The fire team on the Seminole District, Ocala National Forest used the BEHAVE fire model to predict the conditions needed to accomplish a stand-replacement bum. Suitable conditions arose on May 11, 1993...
Cathryn H. Greenberg; Daniel G. Neary; Larry D. Harris
1994-01-01
We tested whether the herpetofuunal response to clearcutting followed by site preparation was similar to high-intensity wildfire foIlowed by salvage logging in sand- pine scrub. Herpetofaunal communities were compared in three replicated 5- to 7-yearpost-disturbance treatments and mature sand-pine forest. The three disturbance treatments were (1) high-intensity...
T. R. Plumb
1967-01-01
ABSTRACT:Combinations of three annual broadcast and individual plant spray applications of brushkiller (a 50-50 mixture of 2,4-dichloro- and 2,4,5-trichlorophenoxyacetic acid) in water-oil emulsion were compared to find the most effective, economical sequence of treatments to kill sprouting scrub oak (Quercus dumosa Nutt.) plants. No one treatment combination had a...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-02
...; Availability of Proposed Low- Effect Habitat Conservation Plan and Associated Documents; Lee County, FL AGENCY... about 75 acres of Florida scrub-jay habitat in Lee County, Florida, for the construction of a 215-acre... Lee County, Florida. The Service listed the scrub-jay as threatened on June 3, 1987 (52 FR 20715). The...
The effects of 11 yr of CO2 enrichment on roots in a Florida scrub-oak ecosystem
Frank Day; Rachel Schroeder; Daniel Stover; Alisha Brown; John Butnor; John Dilustro; Bruce Hungate; Paul Dijkstra; Benjamin Duval; Troy Seiler; Bert Drake; Ross Hinkle
2013-01-01
Uncertainty surrounds belowground plant responses to rising atmospheric CO2 because roots are difficult to measure, requiring frequent monitoring as a result of fine root dynamics and long-term monitoring as a result of sensitivity to resource availability. We report belowground plant responses of a scrub-oak ecosystem in Florida exposed to 11...
Hsieh, Ching-Shui; Cheng, Hsiu-Chi; Lin, Jen-Shiou; Kuo, Shou-Jen; Chen, Yao-Li
2014-01-01
This trial was designed to compare the efficacy of 4% chlorhexidine gluconate (CHG) with normal saline (NS) as a predisinfection skin-scrub solution prior to standard presurgical skin preparation. Data was collected at a single transplantation center where patients electing resection of hepatic tumors were recruited between October 2011 and September 2012. In total, 100 patients were consecutively enrolled for random assignment to either 4% CHG or NS as a predisinfection skin-scrub solution prior to surgery. Our aim was to assess the comparative antiseptic efficacy of CHG in this setting, focusing on cutaneous microbial colonization (at baseline, preoperatively, and postoperatively) and postsurgical site infections as primary outcome measures. Positivity rates of baseline, preoperative, and postoperative cultures were similar for both groups, showing significant declines (relative to baseline) after skin preparation and no significant postsurgical rebound. Rates of surgical site infection were also similar in both groups (CHG, 6.0%; NS, 4.1%; P = 1.0). For patients with hepatic tumors undergoing hepatectomy, the effect of 4% CHG as a predisinfection scrub solution was similar to that of NS in terms of skin decontamination and surgical site infections.
Radford, Eleanor J; Fotis, Theo
2018-01-01
Operating theatre scrub nurses (OTSNs) are not required to have undertaken a secondary or specialist post-registration theatre qualification to work in the operating theatre (OT) setting in the UK. From the systematic review there is only very limited literature or research in how technical scrub skills are acquired. This study explores the lived experiences of OTSNs learning technical scrub skills. The study employed the qualitative methodology of interpretative phenomenological analysis. Data was collected from six participating OTSNs using semi-structured interviews. Four superordinate themes emerged: How technical scrub skills are established, Gatekeepers, How the learner feels whilst learning and, Reflections of the experienced scrub nurse. The study found that the experiences of OTSNs learning technical scrub skills are varied and a variety of teaching and learning methods are utilised. These experiences were influenced by the team, mentor and surgeon within the OT environment. Lived experiences were also influenced by organisational structure and service pressures within the NHS.
Wheeler, Sarah S.; Langevin, Stanley; Woods, Leslie; Carroll, Brian D.; Vickers, Winston; Morrison, Scott A.; Chang, Gwong-Jen J.; Reisen, William K.
2011-01-01
Abstract The devastating effect of West Nile virus (WNV) on the avifauna of North America has led zoo managers and conservationists to attempt to protect vulnerable species through vaccination. The Island Scrub-Jay (Aphelocoma insularis) is one such species, being a corvid with a highly restricted insular range. Herein, we used congeneric Western Scrub-Jays (Aphelocoma californica) to test the efficacy of three WNV vaccines in protecting jays from an experimental challenge with WNV: (1) the Fort Dodge West Nile-Innovator® DNA equine vaccine, (2) an experimental DNA plasmid vaccine, pCBWN, and (3) the Merial Recombitek® equine vaccine. Vaccine efficacy after challenge was compared with naïve and nonvaccinated positive controls and a group of naturally immune jays. Overall, vaccination lowered peak viremia compared with nonvaccinated positive controls, but some WNV-related pathology persisted and the viremia was sufficient to possibly infect susceptible vector mosquitoes. The Fort Dodge West Nile-Innovator DNA equine vaccine and the pCBWN vaccine provided humoral immune priming and limited side effects. Five of the six birds vaccinated with the Merial Recombitek vaccine, including a vaccinated, non-WNV challenged control, developed extensive necrotic lesions in the pectoral muscle at the vaccine inoculation sites, which were attributed to the Merial vaccine. In light of the well-documented devastating effects of high morbidity and mortality associated with WNV infection in corvids, vaccination of Island Scrub-Jays with either the Fort Dodge West Nile-Innovator DNA vaccine or the pCBWN vaccine may increase the numbers of birds that would survive an epizootic should WNV become established on Santa Cruz Island. PMID:21438693
Colour coding scrubs as a means of improving perioperative communication.
Litak, Dominika
2011-05-01
Effective communication within the operating department is essential for achieving patient safety. A large part of the perioperative communication is non-verbal. One type of non-verbal communication is 'object communication', the most common form of which is clothing. The colour coding of clothing such as scrubs has the potential to optimise perioperative communication with the patients and between the staff. A colour contains a coded message, and is a visual cue for an immediate identification of personnel. This is of key importance in the perioperative environment. The idea of colour coded scrubs in the perioperative setting has not been much explored to date and, given the potential contributiontowards improvement of patient outcomes, deserves consideration.
1906-10-01
pressure, almost petechial in character, as if there was a slight admixture of typhus infection. Such cases were always serious. Typhoid fever is not rare...of typhoid fever , 15 of typhus, and 9 of recurrent fever . The number of typhoid- fever cases, how- ever, rapidly increased up to 951 on August 26...east of Lake Baikal (about 570,000 men), was as follows: Dysentery....................... ............... Typhoid fever
[Sanitary and epidemiological supply for the Russian Army during the First World War (1914-1918)].
gorelova, L E; Loktev, A E
2014-02-01
At the beginning of the First World War the most typical diseases in the Russian Army were typhoid, typhus, diphtheria, cholera, smallpox and other infectious diseases. At the beginning of the First World War the level of infectious morbidity was significantly low, but further increased and pandemic risk arose. Servicemen were mostly ill with typhus, relapsing fever, flux, cholera, smallpox and typhoid. The highest mortality rate was registered in patients with cholera, typhus and typhoid. According the prewar deployment program of the Russian Army anti-epidemiologic facilities were established. By the end of war were established 110 sanitary-and-hygienic and 90 disinfection units. However, organization of anti-epidemiologic security was unsatisfactory. Due to lack of specialists and equipment anti-epidemiologic facilities of units were under strength. Commanders of sanitary units and sanitary service had not enough resources for operational service in the Forces and facilities of rear area.
[Epidemics and disease during the Revolution Period in Mexico].
Sanfilippo-Borrás, José
2010-01-01
The health condition in Mexico was bad around de beginning of the revolutionary period. The movement of troops led the development of epidemics like yellow fever, typhus, smallpox, and influenza that were enhance with natural disasters and hunger in whole country, from cost to cost and in the north big cities like Monterrey, Guadalajara and Saltillo. Doctor Liceaga conducted a well planned campaign against yellow fever eradicating water stagnant deposits in order to combat the vector transmission, the Aedes aegypti, mosquito with satisfactory results. The first smallpox epidemic in the XX Century in Mexico was in 1916. The Mexican physicians used the smallpox vaccine against this epidemic. An American physician named Howard Taylor Ricketts arrived to Mexico for studying the typhus transmission. Accidentally he had been infected and finally, he died from typhus. Definitively, the epidemics predominate along de revolutionary period in Mexico.
Effect of scrub oak and associated ground cover on soil moisture
Arthur R. Eschner
1960-01-01
Planting experiments have been conducted for the past 10 years in the scrub oak type at the Delaware-Lehigh Experimental Forest in eastern Pennsylvania. The object of these experiments is to find a practical method of establishing a high forest of greater value than the area's present cover. In the course of these studies it was suggested that soil moisture might...
Effect of elevated CO2 on coarse-root biomass in Florida scrub detected by ground-penetrating radar
Daniel B. Stover; Frank P. Day; John R Butnor; Bert G. Drake
2007-01-01
Growth and distribution of coarse roots in time and space represent a gap in our understanding of belowground ecology. Large roots may play a critical role in carbon sequestration belowground. Using ground-penetrating radar (GPR), we quantified coarseroot biomass from an open-top chamber experiment in a scrub-oak ecosystem at Kennedy Space Center, Florida, USA. GPR...
Kitsongsermthon, J; Duangweang, K; Kreepoke, J; Tansirikongkol, A
2017-11-01
The plastic microbeads, used in many cleansers, will be banned in cosmetic and personal care products within 2017 since they are non-degradable and can disturb the living organisms in water reservoirs. Various choices of biodegradable beads are commercially available, but their efficacy has not been proven yet. This study aimed to compare the cleansing efficacy in dirt and sebum removal aspects of three types of exfoliating beads. The gel scrubs with polyethylene (PE) beads, mannan beads or wax beads, were formulated and evaluated for their stability. The in vivo evaluation was done in 38 healthy volunteers and the skin irritation, efficacy for dirt and sebum removal were measured by Mexameter ® , Colorimeter ® , and Sebumeter ® , respectively. The selected gel scrubs did not cause an irritation in any volunteers. The differences in dirt residues between before and after scrubbing were not statistically significant among three gel scrubs and the similar result was also reported in the sebum removal study. All gel scrubs demonstrated the comparable cleansing efficacy in term of dirt and sebum removal. Thus, mannan beads and wax beads may be replaced non-biodegradable PE beads to achieve the similar cleansing effect. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Bolstering Skin Grafts With a Surgical Scrub Brush: A Cost-effective Solution.
Buller, Mitchell; Lee, Thomas J; Davis, Jared; Wilhelmi, Bradon J
2017-01-01
Objective: The objective of this article is to review the methods currently used for the bolstering of skin grafts and compare their advantages and disadvantages with those of the dry, sterile surgical scrub brush. We report a series of cases performed at a single institution and compare the cost-effectiveness, application, and limitations of this method with other options for skin graft bolstering. Methods: A PubMed search using the parameters "(bolster) AND skin graft" was conducted, yielding 85 results. A total of 40 publications met the criteria for our literature review. The costs of the foam bolsters utilized as stents for skin grafts were obtained from the Central Supply and Resource Division of the University of Louisville Hospital for a cost analysis. The cost per square centimeter of each bolster material was calculated. Results: At $0.003/cm 2 , the 3M Reston foam is the most inexpensive of the 3 bolster materials analyzed. The dry, sterile surgical scrub brush has a similar cost at $0.006/cm 2 but carries the advantage of sterility. The material cost of negative pressure wound therapy is $0.47/cm 2 , and the cost of the system as a whole makes it a much more expensive alternative. In 6 patients with defects of varying size and location, the scrub brush bolster showed a near 100% graft take and no complications. Conclusions: The dry, sterile surgical scrub brush presents a readily available and low-cost option for the stenting of small skin grafts and should be considered a viable method in the armamentarium of available skin graft bolsters.
Dzul-Rosado, Karla; Lugo-Caballero, Cesar; Tello-Martin, Raul; López-Avila, Karina; Zavala-Castro, Jorge
2017-01-01
Murine typhus is a rickettsiosis caused by Rickettsia typhi , whose transmission is carried out by rat fleas in urban settlements as classically known, but it also has been related to cat fleas in a sub-urban alternative cycle that has been suggested by recent reports. These studies remarks that in addition to rats, other animals like cats, opossums and dogs could be implied in the transmission of Rickettsia typhi as infected fleas obtained from serologically positive animals have been detected in samples from endemic areas. In Mexico, the higher number of murine typhus cases have been detected in the Yucatan peninsula, which includes a great southeastern region of Mexico that shows ecologic characteristics similar to the sub-urban alternative cycle recently described in Texas and California at the United States. To find out which are the particular ecologic characteristics of murine typhus transmission in this region, we analyzed blood and Rhipicephalus sanguineus ticks obtained from domestic dogs by molecular approaches, demonstrating that both samples were infected by Rickettsia typhi . Following this, we obtained isolates that were analyzed by genetic sequencing to corroborate this infection in 100% of the analyzed samples. This evidence suggests for the first time that ticks and dogs could be actively participating in the transmission of murine typhus, in a role that requires further studies for its precise description.
[Struggle against typhus in the Caucasian front during the 1st World War].
Karatepe, Mustafa
2002-01-01
As an infectious disease, typhus has triggered many epidemics during the course of wars and caused thousands of death all through the ages. The French physician Charles Nicolle (1886-1936) defined its agent as a louse transferring the disease from man to man in 1909 and was awarded the Nobel Prize in 1928. Many cases were reported during the 1st World War both in the European and the Ottoman armies; and one of the most severe epidemics broke in the Caucasian front; a great number of civilians and soldiers died at winter in 1914 and 1915. Lice had to be destroyed in order to prevent the epidemic, but etuves in the Caucasian front was too few to achieve it. Clothes were cleansed in ovens by means of a method proposed by Dr. Abdülkadir Noyan (1886-1977). On March 28, 1915 the first typhus vaccination, obtained from the infected blood of the patients, was applied by Dr. Tevfik Salim (Saklam) (1882-1963). In 1916 Dr. Ahmet Fikri Tüzer discovered a disinfection apparatus called "buğu sandiği" (vapour box) which was widely used in the Caucasian front after 1917. This apparatus was highly useful in controlling the typhus epidemics. 164 health officers lost their lifes in the Caucasian front between 1914-1918, in addition, 7310 military casualties were recorded from 1915 to the end of the war.
Investigation of new hypergol scrubber technology
NASA Technical Reports Server (NTRS)
Glasscock, Barbara H.
1994-01-01
The ultimate goal of this work is to minimize the liquid waste generated from the scrubbing of hypergolic vent gases. In particular, nitrogen tetroxide, a strong oxidizer used in hypergolic propellant systems, is currently scrubbed with a sodium hydroxide solution resulting in a hazardous liquid waste. This study investigated the use of a solution of potassium hydroxide and hydrogen peroxide for the nitrogen textroxide vent scrubber system. The potassium nitrate formed would be potentially usable as a fertilizer. The hydrogen peroxide is added to convert the potassium nitrite that is formed into more potassium nitrate. Smallscale laboratory tests were conducted to establish the stability of hydrogen peroxide in the proposed scrubbing solution and to evaluate the effectiveness of hydrogen peroxide in converting nitrite to nitrate.
Chlorhexidine avoids skin bacteria recolonization more than triclosan.
Macias, Juan H; Alvarez, Mildred F; Arreguin, Virginia; Muñoz, Juan M; Macias, Alejandro E; Alvarez, Jose A
2016-12-01
We do not know whether differences exist between the residual effect of 2% chlorhexidine in 70% isopropyl alcohol when compared with 1% triclosan in 70% isopropyl alcohol. Using an analytic, longitudinal, controlled, and comparative experimental trial, with blinded measurements, we recruited healthy, adult volunteers from the University of Guanajuato who completed a stabilization phase of skin microbiota and had no history of skin allergies. Four 25-cm 2 areas of the inner surface of the forearms were designated for study: unscrubbed control for establishing baseline bacterial counts, scrubbed control with tridistilled water, scrubbed with chlorhexidine, and scrubbed with triclosan. Quantitative cultures were taken of all the areas at 0, 3, and 24 hours, using agar plates with neutralizing agents. A total of 135 healthy volunteers were tested. At 24 hours, the unscrubbed control counts were 288 CFU/cm 2 , whereas the scrubbed control counts were 96 CFU/cm 2 ; 24 CFU/cm 2 for chlorhexidine and 96 CFU/cm 2 for triclosan (Kruskal-Wallis χ 2 H = 64.27; P <.001). Chlorhexidine is the best antiseptic option when a prolonged antiseptic effect is needed; for instance, when implanting medical devices or performing surgical procedures. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Tick-borne typhus fever of northern Asia: some characteristics of the pathogenesis.
Nelyubov, M V
2002-09-01
Morphological changes in the viscera of albino mice were studied over the course of North Asia typhus fever. In general, the microcirculatory bed in the studied organs (brain, liver, spleen, peritoneum, and testicle) corresponded to angioparalytical capillary and venular hyperemia. Macrophagic reaction (proliferation of stellate macrophages) transformed into granulomatous reaction in the course of the experiment. Macrophagic reaction of the spleen was characterized by blurred follicular pattern. In the testes a tendency to the loss of normal spermatogenesis was observed.
Queensland tick typhus: three cases with unusual clinical features.
Wilson, P A; Tierney, L; Lai, K; Graves, S
2013-07-01
Queensland tick typhus (QTT), caused by Rickettsia australis, is usually a relatively mild illness but can occasionally be severe. We describe three cases of probable QTT with unusual clinical features, namely splenic infarction, fulminant myopericarditis and severe leukocytoclastic vasculitis. QTT may present with uncommon clinical features in addition to the more common manifestations. A high index of suspicion enables specific antibiotic therapy that may hasten recovery. © 2013 The Authors; Internal Medicine Journal © 2013 Royal Australasian College of Physicians.
Kim, Jong Bin; Lee, Jaehoon
2017-01-01
Purpose The aim of the present study was to identify the radiation hazards to vascular surgeons and scrub nurses working in mobile fluoroscopy equipped hybrid vascular operation rooms; additionally, to estimate cumulative cancer risk due to certain exposure dosages. Methods The study was conducted prospectively in 71 patients (53 men and 18 women) who had undergone vascular intervention at our hybrid vascular theater for 6 months. OEC 9900 fluoroscopy was used as mobile C-arm. Exposure dose (ED) was measured by attaching optically stimulated luminescence at in and outside of the radiation protectors. To measure X-ray scatter with the anthropomorphic phantom model, the dose was measured at 3 distances (20, 50, 100 cm) and 3 angles (horizontal, upward 45°, downward 45°) using a personal gamma radiation dosimeter, Ecotest CARD DKG-21, for 1, 3, 5, 10 minutes. Results Lifetime attributable risk of cancer was estimated using the approach of the Biological Effects of Ionizing Radiation report VII. The 6-month ED of vascular surgeons and scrub nurses were 3.85, 1.31 mSv, respectively. The attenuation rate of lead apron, neck protector and goggle were 74.6%, 60.6%, and 70.1%, respectively. All cancer incidences among surgeons and scrub nurses correspond to 2,355 and 795 per 100,000 persons. The 10-minute dose at 100-cm distance was 0.004 mSv at horizontal, 0.009 mSv at downward 45°, 0.003 mSv at upward 45°. Conclusion Although yearly radiation hazards for vascular surgeons and scrub nurses are still within safety guidelines, protection principles can never be too stringent when aiming to minimize the cumulative harmful effects. PMID:28289670
Surgical scrubbing: can we clean up our carbon footprints by washing our hands?
Somner, J E A; Stone, N; Koukkoulli, A; Scott, K M; Field, A R; Zygmunt, J
2008-11-01
A growing scientific consensus states that the global climate is changing and that human activity is responsible for these changes. It folLows that each of us has a responsibility to look at how our own lives impact on the environment. This study aimed to investigate water use during surgical scrubbing. Two water delivery systems were assessed to see whether technological innovation can promote more 'environmentally friendly' scrubbing behaviour. At least 10 different individuals, comprising surgeons, assistants and scrub nurses, were observed at two sites. Twenty-five separate surgical scrubs were observed in each location and the length of time for which the tap was on recorded. The tap was on during surgical scrubbing for a mean of 2 min 23 s at Gartnavel General Hospital (maximum: 4 min 37 s; minimum: 49 s; SD: 55 s) and for a mean of 1 min 7 s at Stobhill Hospital (maximum: 2 min 25 s; minimum: 19 s; SD: 33 s). The mean 'tap on' time (in seconds) at Gartnavel was significantly greater than that at Stobhill [t(39.5)=P<0.001]. A different tap design resulted in a net saving of 5.7 L of hot water, approximately 600 kJ of energy and 80 g of carbon dioxide emitted per surgical scrub. Surgical scrubbing is a ubiquitous procedure performed daily in healthcare settings. A simple technological solution can reduce water and energy use by modifying hand-washing behaviour and thereby reduce the carbon footprint of surgical scrubbing.
Factors that influence the non-technical skills performance of scrub nurses: a prospective study.
Kang, Evelyn; Massey, Debbie; Gillespie, Brigid M
2015-12-01
To identify and describe the factors that impact on the performance of scrub nurses' non-technical skills performance during the intra-operative phase of surgery. Non-technical skills have been identified as important precursors to errors in the operating room. However, few studies have investigated factors influencing non-technical skills of scrub nurses. Prospective observational study. Structured observations were performed on a sample of 182 surgical procedures across eight specialities by two trained observers from August 2012-April 2013 at two hospital sites. Participants were purposively selected scrub nurses. Bivariate correlations and a multiple linear regression model were used to identify associations among length of surgery, patients' acuity using the American Society of Anesthesiologists classification system, team familiarity, number of occasions scout nurses leave the operating room, change of scout nurse and the outcome, the non-technical skills performance of scrub nurses. Patient acuity and team familiarity were the strongest predictors of scrub nurses' non-technical skills performance at hospital site A. There were no correlations between the predictors and the performance of scrub nurses at hospital site B. A dedicated surgical team and patient acuity potentially influence the performance of scrub nurses' non-technical skills. Familiarity with team members foster advanced planning, thus minimizing distractions and interruptions that impact on scrub nurses' performance. Development of interventions aimed at improving non-technical skills has the potential to make a substantial difference and enhance patient care. © 2015 John Wiley & Sons Ltd.
Flea-Borne Rickettsioses in the North of Caldas Province, Colombia
Montoya, Viviana; Martínez, Alejandra; Mercado, Marcela; De la Ossa, Alberto; Vélez, Carolina; Estrada, Gloria; Pérez, Jorge E.; Faccini-Martínez, Alvaro A.; Labruna, Marcelo B.; Valbuena, Gustavo
2013-01-01
Abstract Rickettsia typhi and R. felis are the etiological agents of murine typhus and flea-borne spotted fever, respectively. Both are emerging acute febrile zoonotic diseases for which fleas are vectors; they also have similar clinical characteristics and global distribution. In 2005, we identified the circulation of murine typhus in 6 towns within the mountainous coffee-growing area north of Caldas, Colombia. We now report the specific seroprevalence against R. typhi and R. felis, and associated risk factors in 7 towns of this province. The combined seroprevalence against the 2 flea-borne rickettsioses is the highest yet reported in the literature: 71.7% (17.8% for R. felis, 25.2% for R. typhi, and 28.7% for both). We also report a prospective analysis of 26 patients with a febrile illness compatible with rickettsioses, including murine typhus; 9 of these patients had a rickettsiosis. This supports our sero-epidemiological results and highlights the diagnostic complexity of febrile syndromes in this region. PMID:23473218
Ruggi, Giovanni; Carneglia, Luca
2002-01-01
The authors recall the louse-borne typhus that took place in Leghorn in 1817. They analyse its causes and the health measures adopted to face it. Out of the historical reconstruction, there arise some issues on both the coming up again of such risk and the role played by health measures. Data concern the chronicles and the medical literature of those days. The method adopted implies comparison between historical circumstances, medical debate and provisions: in 1817 an epidemic of typhus exanthematicus caused hundreds of deaths and gave rise to much medical controversy incapable, however, of improving the existing knowledge. The analysis show a lack of health protection programs and a fallacious medical approach which did not help understand the relationship between pediculosis and disease. Following the health risks posed by migration pressures, this study stresses the importance of keeping the health agents' freedom of judgment away from political and administrative authority.
Multispacer typing of Rickettsia prowazekii enabling epidemiological studies of epidemic typhus.
Zhu, Yong; Fournier, Pierre-Edouard; Ogata, Hiroyuki; Raoult, Didier
2005-09-01
Currently, there is no tool for typing Rickettsia prowazekii, the causative agent of epidemic typhus, currently considered a potential bioterrorism agent, at the strain level. To test if the multispacer typing (MST) method could differentiate strains of R. prowazekii, we amplified and sequenced the 25 most variable intergenic spacers between the R. prowazekii and R. conorii genomes in five strains and 10 body louse amplicons of R. prowazekii from various geographic origins. Two intergenic spacers, i.e., rpmE/tRNA(fMet) and serS/virB4, were variable among tested R. prowazekii isolates and allowed identification of three and two genotypes, respectively. When the genotypes obtained from the two spacers were combined, we identified four different genotypes. MST demonstrated that several R. prowazekii strains circulated in human body lice during an outbreak of epidemic typhus in Burundi. This may help to discriminate between natural and intentional outbreaks. Our study supports the usefulness of MST as a versatile method for rickettsial strain genotyping.
[Petechial typhus in Napoleonic Italy. Scientific debate and the role of Giovanni Rasori].
Sabbatani, Sergio
2006-12-01
During the Napoleonic wars, an epidemic recrudescence of petechial typhus was observed throughout Europe. In Italy, the epidemic first broke out in Genoa, in 1799, coming from southern France, during the sieges of the Austro-Hungarian army. Giovanni Rasori, a young Republican physician and man of the sciences, supported the besieged and contributed to defend the city. From the beginning, Rasori identified the cause of the epidemic in petechial typhus, being able to evaluate its clinical presentation, and developed a pathogenetic theory, known as contrastimulus. At that time, this theory obtained some success, though opposed by the academic establishment in Lombardy. In this article, we present the medical and philosophical ideas which, in the period between the 18th and 19th century, pervaded medical Italian culture. Furthermore, a biographic profile of Giovanni Rasori is described, a courageous scientist who did not disdain to take part in political and cultural Italian life during a historical period that was to become important for the future fortunes of Italy.
Matsuda, Tritia; Turschak, Greta; Brehme, Cheryl; Rochester, Carlton; Mitrovich, Milan; Fisher, Robert
2011-01-01
We investigated the effect of broad-scale wildfire on ground foraging ants within southern California. In October and November of 2003, two wildfires burned large portions of the wildlands within San Diego County. Between January 2005 and September 2006, we surveyed 63 plots across four sites to measure the effect of the fires on the ant assemblages present in four vegetation types: 1) coastal sage scrub, 2) chaparral, 3) grassland, and 4) woodland riparian. Thirty-six of the 63 plots were sampled before the fires between March 2001 and June 2003. Mixed model regression analyses, accounting for the burn history of each plot and our pre- and postfire sampling efforts, revealed that fire had a negative effect on ant species diversity. Multivariate analyses showed that ant community structure varied significantly among the four vegetation types, and only the ant assemblage associated with coastal sage scrub exhibited a significant difference between burned and unburned samples. The most notable change detected at the individual species level involved Messor andrei (Mayr), which increased from <1% of prefire coastal sage scrub ant samples to 32.1% in burned plots postfire. We theorize that M. andrei responded to the increase of bare ground and postfire seed production, leading to an increase in the detection rate for this species. Collectively, our results suggest that wildfires can have short-term impacts on the diversity and community structure of ground foraging ants in coastal sage scrub. We discuss these findings in relation to management implications and directions for future research.
NASA Astrophysics Data System (ADS)
Sánchez, Ana M.; Peco, Begoña
2004-07-01
This paper analyses the relationship between Lavandula stoechas subsp. pedunculata, a common Mediterranean scrub species in central Iberia, and perennial grasslands. While Lavandula gives rise to almost monospecific formations in intermediate and upper hill zones, perennial grasses occupy the low areas. The proposed explanatory hypothesis for this spatial distribution is that the scrub is unable to establish itself in grasslands with heavy spatial occupation. We designed two experiments to test this hypothesis, one which analysed the effect of perennial grass cover on Lavandula establishment, and another which focused on its influence on previously implanted seedling survival and growth, distinguishing the effect of shoot and root interference. The results show negative interference during establishment and later in the use of light and nutrients. This results in a very low overall survival probability, with only 1.4% of seedlings surviving the first growth period. This low success rate explains the existence of a clear spatial segregation between scrub patches and perennial-dominated grasslands.
Approach to Clinical Syndrome of Jaundice and Encephalopathy in Tropics
Anand, Anil C.; Garg, Hitendra K.
2015-01-01
A large number of patients present with jaundice and encephalopathy in tropical country like India and acute liver failure is the usual cause. Clinical presentation like ALF is also a complication of many tropical infections, and these conditions may mimic ALF but may have subtle differences from ALF. Moreover, what hepatologists see as acute liver failure in tropics is different from what is commonly described in Western Textbooks. Paracetamol overdose, which is possibly the commonest cause of ALF in UK and USA, is hardly ever seen in India. Most common etiology here is viral hepatitis (hepatitis E > hepatitis B> hepatitis A). Apart from ALF, one may also come across subacute hepatic failure (SAHF) as well as acute-on-chronic liver failure (ACLF) due to viral hepatitis. Interestingly, a host of other conditions can mimic ALF because clinical presentation in these conditions can be dominated by jaundice and encephalopathy. Malarial hepatopathy is possibly the best-known condition out of these and is not an uncommon manifestation of severe malaria. A similar presentation can also be seen in other common infections in tropics such as dengue fever, typhoid fever, leptospirosis, scrub typhus, amoebic liver abscesses, tuberculosis and other bacterial and fungal infections with or without human immunodeficiency virus (HIV) related disease. In many of these conditions, liver failure may not be underlying pathophysiology. Some pregnancy related liver diseases could also present with jaundice and encephalopathy. This review summarizes the commonly seen presentations in tropical country like India, where jaundice and encephalopathy dominate the clinical picture. PMID:26041951
Isolation of a novel Orientia species (O. chuto sp. nov.) from a patient infected in Dubai.
Izzard, Leonard; Fuller, Andrew; Blacksell, Stuart D; Paris, Daniel H; Richards, Allen L; Aukkanit, Nuntipa; Nguyen, Chelsea; Jiang, Ju; Fenwick, Stan; Day, Nicholas P J; Graves, Stephen; Stenos, John
2010-12-01
In July 2006, an Australian tourist returning from Dubai, in the United Arab Emirates (UAE), developed acute scrub typhus. Her signs and symptoms included fever, myalgia, headache, rash, and eschar. Orientia tsutsugamushi serology demonstrated a 4-fold rise in antibody titers in paired serum collections (1:512 to 1:8,192), with the sera reacting strongest against the Gilliam strain antigen. An Orientia species was isolated by the in vitro culture of the patient's acute blood taken prior to antibiotic treatment. The gene sequencing of the 16S rRNA gene (rrs), partial 56-kDa gene, and the full open reading frame 47-kDa gene was performed, and comparisons of this new Orientia sp. isolate to previously characterized strains demonstrated significant sequence diversity. The closest homology to the rrs sequence of the new Orientia sp. isolate was with three strains of O. tsutsugamushi (Ikeda, Kato, and Karp), with a nucleotide sequence similarity of 98.5%. The closest homology to the 47-kDa gene sequence was with O. tsutsugamushi strain Gilliam, with a nucleotide similarity of 82.3%, while the closest homology to the 56-kDa gene sequence was with O. tsutsugamushi strain TA686, with a nucleotide similarity of 53.1%. The molecular divergence and geographically unique origin lead us to believe that this organism should be considered a novel species. Therefore, we have proposed the name "Orientia chuto," and the prototype strain of this species is strain Dubai, named after the location in which the patient was infected.
Isolation of a Novel Orientia Species (O. chuto sp. nov.) from a Patient Infected in Dubai ▿
Izzard, Leonard; Fuller, Andrew; Blacksell, Stuart D.; Paris, Daniel H.; Richards, Allen L.; Aukkanit, Nuntipa; Nguyen, Chelsea; Jiang, Ju; Fenwick, Stan; Day, Nicholas P. J.; Graves, Stephen; Stenos, John
2010-01-01
In July 2006, an Australian tourist returning from Dubai, in the United Arab Emirates (UAE), developed acute scrub typhus. Her signs and symptoms included fever, myalgia, headache, rash, and eschar. Orientia tsutsugamushi serology demonstrated a 4-fold rise in antibody titers in paired serum collections (1:512 to 1:8,192), with the sera reacting strongest against the Gilliam strain antigen. An Orientia species was isolated by the in vitro culture of the patient's acute blood taken prior to antibiotic treatment. The gene sequencing of the 16S rRNA gene (rrs), partial 56-kDa gene, and the full open reading frame 47-kDa gene was performed, and comparisons of this new Orientia sp. isolate to previously characterized strains demonstrated significant sequence diversity. The closest homology to the rrs sequence of the new Orientia sp. isolate was with three strains of O. tsutsugamushi (Ikeda, Kato, and Karp), with a nucleotide sequence similarity of 98.5%. The closest homology to the 47-kDa gene sequence was with O. tsutsugamushi strain Gilliam, with a nucleotide similarity of 82.3%, while the closest homology to the 56-kDa gene sequence was with O. tsutsugamushi strain TA686, with a nucleotide similarity of 53.1%. The molecular divergence and geographically unique origin lead us to believe that this organism should be considered a novel species. Therefore, we have proposed the name “Orientia chuto,” and the prototype strain of this species is strain Dubai, named after the location in which the patient was infected. PMID:20926708
Thomas, Rwituja; Puranik, Preeti; Kalal, Bhuvanesh; Britto, Carl; Kamalesh, Savitha; Rego, Sylvan; Shet, Anita
2016-06-30
Rickettsial infections are re-emerging in the Indian subcontinent, especially among children. Understanding geographical and clinical epidemiology will facilitate early diagnosis and management. Children aged <18yrs hospitalized with clinically-diagnosed rickettsial fever were reviewed retrospectively. Frequency distributions and odds ratios were calculated from tabulated data. Among 262 children hospitalized between January 2008-December 2012, median age was five years, and 61% were male children. Hospitalized cases increased steadily every year, with the highest burden (74%) occurring between September and January each year. Mean duration of fever was 11.5 days. Rash was present in 54.2% (142/262) of children, with 37.0% involving palms and soles. Prevalence of malnutrition was high (45% of children were underweight and 28% had stunting). Retinal vasculitis was seen in 13.7% (36/262), and the risk appeared higher in females. Severe complications were seen in 29% (purpura fulminans, 7.6%; meningitis and meningoencephalitis, 28%; septic shock, 1.9%; acute respiratory distress syndrome, 1.1%). Complications were more likely to occur in anemic children. Positive Weil-Felix test results (titers ≥1:160) were seen in 70% of cases. Elevated OX-K titers suggestive of scrub typhus were seen in 80% (147/184). Patients were treated with chloramphenicol (32%) or doxycycline (68%). Overall mortality among hospitalised children was 1.9%. This five-year analysis from southern India shows a high burden and increasing trend of rickettsial infections among children. The occurrence of retinal vasculitis and a high rate of severe complications draw attention to the need for early diagnosis and management of these infections.
Batty, Elizabeth M; Chaemchuen, Suwittra; Blacksell, Stuart; Richards, Allen L; Paris, Daniel; Bowden, Rory; Chan, Caroline; Lachumanan, Ramkumar; Day, Nicholas; Donnelly, Peter; Chen, Swaine; Salje, Jeanne
2018-06-01
Orientia tsutsugamushi is a clinically important but neglected obligate intracellular bacterial pathogen of the Rickettsiaceae family that causes the potentially life-threatening human disease scrub typhus. In contrast to the genome reduction seen in many obligate intracellular bacteria, early genetic studies of Orientia have revealed one of the most repetitive bacterial genomes sequenced to date. The dramatic expansion of mobile elements has hampered efforts to generate complete genome sequences using short read sequencing methodologies, and consequently there have been few studies of the comparative genomics of this neglected species. We report new high-quality genomes of O. tsutsugamushi, generated using PacBio single molecule long read sequencing, for six strains: Karp, Kato, Gilliam, TA686, UT76 and UT176. In comparative genomics analyses of these strains together with existing reference genomes from Ikeda and Boryong strains, we identify a relatively small core genome of 657 genes, grouped into core gene islands and separated by repeat regions, and use the core genes to infer the first whole-genome phylogeny of Orientia. Complete assemblies of multiple Orientia genomes verify initial suggestions that these are remarkable organisms. They have larger genomes compared with most other Rickettsiaceae, with widespread amplification of repeat elements and massive chromosomal rearrangements between strains. At the gene level, Orientia has a relatively small set of universally conserved genes, similar to other obligate intracellular bacteria, and the relative expansion in genome size can be accounted for by gene duplication and repeat amplification. Our study demonstrates the utility of long read sequencing to investigate complex bacterial genomes and characterise genomic variation.
Pesendorfer, Mario B.; Baker, Christopher M.; Stringer, Martin; McDonald-Madden, Eve; Bode, Michael; McEachern, A. Kathryn; Morrison, Scott A.; Sillett, T. Scott
2018-01-01
Seed dispersal by birds is central to the passive restoration of many tree communities. Reintroduction of extinct seed dispersers can therefore restore degraded forests and woodlands. To test this, we constructed a spatially explicit simulation model, parameterized with field data, to consider the effect of different seed dispersal scenarios on the extent of oak populations. We applied the model to two islands in California's Channel Islands National Park (USA), one of which has lost a key seed disperser.We used an ensemble modelling approach to simulate island scrub oak (Quercus pacifica) demography. The model was developed and trained to recreate known population changes over a 20-year period on 250-km2 Santa Cruz Island, and incorporated acorn dispersal by island scrub-jays (Aphelocoma insularis), deer mice (Peromyscus maniculatus) and gravity, as well as seed predation. We applied the trained model to 215-km2 Santa Rosa Island to examine how reintroducing island scrub-jays would affect the rate and pattern of oak population expansion. Oak habitat on Santa Rosa Island has been greatly reduced from its historical extent due to past grazing by introduced ungulates, the last of which were removed by 2011.Our simulation model predicts that a seed dispersal scenario including island scrub-jays would increase the extent of the island scrub oak population on Santa Rosa Island by 281% over 100 years, and by 544% over 200 years. Scenarios without jays would result in little expansion. Simulated long-distance seed dispersal by jays also facilitates establishment of discontinuous patches of oaks, and increases their elevational distribution.Synthesis and applications. Scenario planning provides powerful decision support for conservation managers. We used ensemble modelling of plant demographic and seed dispersal processes to investigate whether the reintroduction of seed dispersers could provide cost-effective means of achieving broader ecosystem restoration goals on California's second-largest island. The simulation model, extensively parameterized with field data, suggests that re-establishing the mutualism with seed-hoarding jays would accelerate the expansion of island scrub oak, which could benefit myriad species of conservation concern.
Wet scrubbing of biomass producer gas tars using vegetable oil
NASA Astrophysics Data System (ADS)
Bhoi, Prakashbhai Ramabhai
The overall aims of this research study were to generate novel design data and to develop an equilibrium stage-based thermodynamic model of a vegetable oil based wet scrubbing system for the removal of model tar compounds (benzene, toluene and ethylbenzene) found in biomass producer gas. The specific objectives were to design, fabricate and evaluate a vegetable oil based wet scrubbing system and to optimize the design and operating variables; i.e., packed bed height, vegetable oil type, solvent temperature, and solvent flow rate. The experimental wet packed bed scrubbing system includes a liquid distributor specifically designed to distribute a high viscous vegetable oil uniformly and a mixing section, which was designed to generate a desired concentration of tar compounds in a simulated air stream. A method and calibration protocol of gas chromatography/mass spectroscopy was developed to quantify tar compounds. Experimental data were analyzed statistically using analysis of variance (ANOVA) procedure. Statistical analysis showed that both soybean and canola oils are potential solvents, providing comparable removal efficiency of tar compounds. The experimental height equivalent to a theoretical plate (HETP) was determined as 0.11 m for vegetable oil based scrubbing system. Packed bed height and solvent temperature had highly significant effect (p0.05) effect on the removal of model tar compounds. The packing specific constants, Ch and CP,0, for the Billet and Schultes pressure drop correlation were determined as 2.52 and 2.93, respectively. The equilibrium stage based thermodynamic model predicted the removal efficiency of model tar compounds in the range of 1-6%, 1-4% and 1-2% of experimental data for benzene, toluene and ethylbenzene, respectively, for the solvent temperature of 30° C. The NRTL-PR property model and UNIFAC for estimating binary interaction parameters are recommended for modeling absorption of tar compounds in vegetable oils. Bench scale experimental data from the wet scrubbing system would be useful in the design and operation of a pilot scale vegetable oil based system. The process model, validated using experimental data, would be a key design tool for the design and optimization of a pilot scale vegetable oil based system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pierce, R.; Peters, T.; Crowder, M.
2011-09-27
Researchers successfully demonstrated the chemistry and process equipment of the Caustic-Side Solvent Extraction (CSSX) flowsheet using MaxCalix for the decontamination of high level waste (HLW). The demonstration was completed using a 12-stage, 2-cm centrifugal contactor apparatus at the Savannah River National Laboratory (SRNL). This represents the first CSSX process demonstration of the MaxCalix solvent system with Savannah River Site (SRS) HLW. Two tests lasting 24 and 27 hours processed non-radioactive simulated Tank 49H waste and actual Tank 49H HLW, respectively. Conclusions from this work include the following. The CSSX process is capable of reducing {sup 137}Cs in high level radioactivemore » waste by a factor of more than 40,000 using five extraction, two scrub, and five strip stages. Tests demonstrated extraction and strip section stage efficiencies of greater than 93% for the Tank 49H waste test and greater than 88% for the simulant waste test. During a test with HLW, researchers processed 39 liters of Tank 49H solution and the waste raffinate had an average decontamination factor (DF) of 6.78E+04, with a maximum of 1.08E+05. A simulant waste solution ({approx}34.5 liters) with an initial Cs concentration of 83.1 mg/L was processed and had an average DF greater than 5.9E+03, with a maximum DF of greater than 6.6E+03. The difference may be attributable to differences in contactor stage efficiencies. Test results showed the solvent can be stripped of cesium and recycled for {approx}25 solvent turnovers without the occurrence of any measurable solvent degradation or negative effects from minor components. Based on the performance of the 12-stage 2-cm apparatus with the Tank 49H HLW, the projected DF for MCU with seven extraction, two scrub, and seven strip stages operating at a nominal efficiency of 90% is {approx}388,000. At 95% stage efficiency, the DF in MCU would be {approx}3.2 million. Carryover of organic solvent in aqueous streams (and aqueous in organic streams) was less than 0.1% when processing Tank 49H HLW. The entrained solvent concentration measured in the decontaminated salt solution (DSS) was as much as {approx}140 mg/L, although that value may be overstated by as much as 50% due to modifier solubility in the DSS. The entrained solvent concentration was measured in the strip effluent (SE) and the results are pending. A steady-state concentration factor (CF) of 15.9 was achieved with Tank 49H HLW. Cesium distribution ratios [D(Cs)] were measured with non-radioactive Tank 49H waste simulant and actual Tank 49H waste. Below is a comparison of D(Cs) values of ESS and 2-cm tests. Batch Extraction-Strip-Scrub (ESS) tests yielded D(Cs) values for extraction of {approx}81-88 for tests with Tank 49H waste and waste simulant. The results from the 2-cm contactor tests were in agreement with values of 58-92 for the Tank 49H HLW test and 54-83 for the simulant waste test. These values are consistent with the reference D(Cs) for extraction of {approx}60. In tests with Tank 49H waste and waste simulant, batch ESS tests measured D(Cs) values for the two scrub stages as {approx}3.5-5.0 for the first scrub stage and {approx}1.0-3.0 for the second scrub stage. In the Tank 49H test, the D(Cs) values for the 2-cm test were far from the ESS values. A D(Cs) value of 161 was measured for the first scrub stage and 10.8 for the second scrub stage. The data suggest that the scrub stage is not operating as effectively as intended. For the simulant test, a D(Cs) value of 1.9 was measured for the first scrub stage; the sample from the second scrub stage was compromised. Measurements of the pH of all stage samples for the Tank 49H test showed that the pH for extraction and scrub stages was 14 and the pH for the strip stages was {approx}7. It is expected that the pH of the second scrub stage would be {approx}12-13. Batch ESS tests measured D(Cs) values for the strip stages to be {approx}0.002-0.010. A high value in Strip No.3 of a test with simulant solution has been attributed to issues associated with the limits of detection for the analytical method. In the 2-cm contactor tests, the first four strip stages of the Tank 49H waste test and all five strip stages in the simulant waste test had higher values than the ESS tests. Only the fifth strip stage D(Cs) value of the Tank 49H waste test matched that of the ESS tests. It is speculated that the less-than-optimal performance of the strip section is caused by inefficiencies in the scrub section. Because strip is sensitive to pH, the elevated pH value in the second scrub stage may be the cause of strip performance. In spite of the D(Cs) values obtained in the scrub and strip sections, testing showed that the solvent system is robust. Average DFs for the process far exceeded targets even though the scrub and strip stages did not function optimally. Correction of the issue in the scrub and strip stages is expected to yield even higher waste DFs.« less
Masticophis flagellum selects florida scrub habitat at multiple spatial scales
Halstead, B.J.; Mushinsky, H.R.; McCoy, E.D.
2009-01-01
The use of space by individual animals strongly influences the spatial extent, abundance, and growth rates of their populations. We analyzed the spatial ecology and habitat selection of Masticophis flagellum (the coachwhip) at three different scales to determine which habitats are most important to this species. Home ranges and mean daily displacements of M. flagellum in Florida were large compared to individuals in other populations of this species. Home ranges contained a greater proportion of Florida scrub habitat than did the study site as a whole, and individuals selected Florida scrub habitat within their home ranges. For both selection of the home range within the study site and selection of habitats within the home range, mesic cutthroat and hydric swamp habitats were avoided. Standardized selection ratios of Florida scrub patches were positively correlated with lizard abundance. Several non-mutually exclusive mechanisms, including foraging success (prey abundance, prey vulnerability, and foraging efficiency), abundance of refugia, and thermoregulatory opportunity may underlie the selection of Florida scrub by M. flagellum. Historic rarity and anthropogenic loss and fragmentation of Florida scrub habitat, coupled with the long-distance movements, large home ranges, and selection of Florida scrub by M. flagellum, indicate that large contiguous tracts of land containing Florida scrub will be essential for the persistence of M. flagellum in central Florida. ?? 2009 by The Herpetologists' League, Inc.
Stewart, Adam; Armstrong, Mark; Graves, Stephen; Hajkowicz, Krispin
2017-07-01
Rickettsia australis , the etiologic agent of Queensland tick typhus (QTT), is increasingly being recognized as a cause of community-acquired acute febrile illness in eastern Australia. Changing human population demographics, climate change, and increased understanding of expanding vector distribution indicate QTT is an emerging public health threat. This review summarizes the epidemiology, pathogenesis, clinical features, treatment principles, and future directions of this disease. Increased recognition of QTT will enable consideration of and prompt treatment of R. australis infection by clinicians in Australia.
Hermann Mooser, Typhus, Warsaw 1941.
Lindenmann, Jean
2002-01-01
Hermann Mooser (1891-1971), a Swiss rickettsiologist, sent his friend Peyton Rous (1879-1970) of the Rockefeller Institute (New York) a telegram on November 3, 1941, asking for financial help for the manufacture of typhus vaccine in Zurich for the Warsaw Ghetto. His explanatory letter from November 4 reached Rous too late to have any influence on the negative decision (by the Rockefeller Foundation and the American Red Cross) in this matter. Contrary to Weindling's affirmation Mooser was neither in Warsaw in 1941, nor was he a member of the Swiss Sanitary Missions to the eastern front.
75 FR 56133 - Savannah Coastal Refuges' Complex, GA and SC
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-15
..., open waters, forested habitats, scrub/shrub habitats, grasslands, and open lands. All ponds, levees... management programs for impoundments, beaches, wetlands, open waters, forested habitats, scrub/shrub habitats... habitat management strategy. Impoundments, beaches, wetlands, open waters, forested habitats, scrub/shrub...
Simultaneous treatment of SO2 containing stack gases and waste water
NASA Technical Reports Server (NTRS)
Poradek, J. C.; Collins, D. D. (Inventor)
1978-01-01
A process for simultaneously removing sulfur dioxide from stack gases and the like and purifying waste water such as derived from domestic sewage is described. A portion of the gas stream and a portion of the waste water, the latter containing dissolved iron and having an acidic pH, are contacted in a closed loop gas-liquid scrubbing zone to effect absorption of the sulfur dioxide into the waste water. A second portion of the gas stream and a second portion of the waste water are controlled in an open loop gas-liquid scrubbing zone. The second portion of the waste water contains a lesser amount of iron than the first portion of the waste water. Contacting in the openloop scrubbing zone is sufficient to acidify the waste water which is then treated to remove solids originally present.
Use of face masks by non-scrubbed operating room staff: a randomized controlled trial.
Webster, Joan; Croger, Sarah; Lister, Carolyn; Doidge, Michelle; Terry, Michael J; Jones, Ian
2010-03-01
Ambiguity remains about the effectiveness of wearing surgical face masks. The purpose of this study was to assess the impact on surgical site infections (SSIs) when non-scrubbed operating room staff did not wear surgical face masks. Eight hundred twenty-seven participants undergoing elective or emergency obstetric, gynecological, general, orthopaedic, breast or urological surgery in an Australian tertiary hospital were enrolled. Complete follow-up data were available for 811 patients (98.1%). Operating room lists were randomly allocated to a 'Mask group' (all non-scrubbed staff wore a mask) or 'No Mask group' (none of the non-scrubbed staff wore masks). The primary end point, SSI was identified using in-patient surveillance; post discharge follow-up and chart reviews. The patient was followed for up to six weeks. Overall, 83 (10.2%) surgical site infections were recorded; 46/401 (11.5%) in the Masked group and 37/410 (9.0%) in the No Mask group; odds ratio (OR) 0.77 (95% confidence interval (CI) 0.49 to 1.21), p = 0.151. Independent risk factors for surgical site infection included: any pre-operative stay (adjusted odds ratio [aOR], 0.43 (95% CI, 0.20; 0.95), high BMI aOR, 0.38 (95% CI, 0.17; 0.87), and any previous surgical site infection aOR, 0.40 (95% CI, 0.17; 0.89). Surgical site infection rates did not increase when non-scrubbed operating room personnel did not wear a face mask.
Jet Surface Interaction Scrubbing Noise from High Aspect-Ratio Rectangular Jets
NASA Technical Reports Server (NTRS)
Khavaran, Abbas; Bozak, Richard F.
2015-01-01
Concepts envisioned for the future of civil air transport consist of unconventional propulsion systems in the close proximity of the airframe. Distributed propulsion system with exhaust configurations that resemble a high aspect ratio rectangular jet are among geometries of interest. Nearby solid surfaces could provide noise shielding for the purpose of reduced community noise. Interaction of high-speed jet exhaust with structure could also generate new sources of sound as a result of flow scrubbing past the structure, and or scattered noise from sharp edges. The present study provides a theoretical framework to predict the scrubbing noise component from a high aspect ratio rectangular exhaust in proximity of a solid surface. The analysis uses the Greens function (GF) to the variable density Pridmore-Brown equation in a transversely sheared mean flow. Sources of sound are defined as the auto-covariance function of second-rank velocity fluctuations in the jet plume, and are modeled using a RANS-based acoustic analogy approach. Acoustic predictions are presented in an 8:1 aspect ratio rectangular exhaust at three subsonic Mach numbers. The effect of nearby surface on the scrubbing noise component is shown on both reflected and shielded sides of the plate.
SHAWNEE LIME/LIMESTONE SCRUBBING COMPUTERIZED DESIGN/COST-ESTIMATE MODEL USERS MANUAL
The manual gives a general description of the Shawnee lime/limestone scrubbing computerized design/cost-estimate model and detailed procedures for using it. It describes all inputs and outputs, along with available options. The model, based on Shawnee Test Facility scrubbing data...
Medical science in the light of the Holocaust: Departing from a post-war paper by Ludwik Fleck.
Hedfors, Eva
2008-04-01
In scholarly debates, Ludwik Fleck's post-war paper 'Problemy naukoznawstwa [Problems of the Science of Science]', published in 1946, has been taken unanimously to illustrate the epistemology expounded in his monograph Genesis and Development of a Scientific Fact. The paper has also been seen to support parts of the received view of Fleck, notably that he manufactured an anti-typhus vaccine while imprisoned in Buchenwald. However, a different narrative emerges when comparing Fleck's paper with other accounts, also published in 1946 and written by other prisoners alluded to by Fleck in his paper. The situation is further complicated by four papers, published in prestigious scientific journals between 1942 and 1945, by the German medical leader of the typhus studies accounted for by Fleck. In addition, a thus-far neglected paper by Fleck, published in 1946 and summarizing his observations on typhus, discloses his role in the Buchenwald studies. Despite the obvious difficulties with tracing the history behind these works, notably the one on Nazi science, the contention is that what was attempted in Buchenwald in the name of science amounted to pseudoscience. This conclusion is amply supported not only by the accounts given by Fleck's fellow prisoners, but also by his own post-war paper on typhus. Based on the above findings, it is suggested that the mythology about Fleck, established in the 1980s, has been accomplished by a selective reading of his papers and also that the role played by Fleck was more complex than has so far been contemplated.
McCullough, Sarah A; Endress, Bryan A
2012-01-01
In recent years, the use of postfire mulch treatments to stabilize slopes and reduce soil erosion in shrubland ecosystems has increased; however, the potential effects on plant recovery have not been examined. To evaluate the effects of mulching treatments on postfire plant recovery in southern California coastal sage scrub, we conducted a field experiment with three experimental treatments, consisting of two hydromulch products and an erosion control blanket, plus a control treatment. The area burned in 2007, and treatments were applied to six plot blocks before the 2008 growing season. Treatment effects on plant community recovery were analyzed with a mixed effects ANOVA analysis using a univariate repeated measures approach. Absolute plant cover increased from 13 to 90% by the end of the second growing season, and the mean relative cover of exotic species was 32%. The two hydromulch treatments had no effect on any plant community recovery response variable measured. For the erosion control blanket treatment, the amount of bare ground cover at the end of the second growing season was significantly lower (P = 0.01), and greater shrub height was observed (P < 0.01). We conclude that postfire mulch treatments did not provide either a major benefit or negative impact to coastal sage scrub recovery on the study area.
Optimal Irrigation and Debridement of Infected Joint Implants
Schwechter, Evan M.; Folk, David; Varshney, Avanish K.; Fries, Bettina C.; Kim, Sun Jin; Hirsh, David M.
2014-01-01
Acute postoperative and acute, late hematogenous prosthetic joint infections have been treated with 1-stage irrigation and debridement with polyethylene exchange. Success rates, however, are highly variable. Reported studies demonstrate that detergents are effective at decreasing bacterial colony counts on orthopedic implants. Our hypothesis is that the combination of a detergent and an antiseptic would be more effective than using a detergent alone to decrease colony counts from a methicillin-resistant Staphylococcus aureus biofilm-coated titanium alloy disk simulating an orthopedic implant. In our study of various agents tested, chlorhexidine gluconate scrub (antiseptic and detergent) was the most effective at decreasing bacterial colony counts both prereincubation and postreincubation of the disks; pulse lavage and scrubbing were not more effective than pulse lavage alone. PMID:21641757
[The North African plague and Charles Nicolle's theory of infectious diseases].
Ben, Néfissa Kmar; Moulin, Anne Marie
2010-01-01
Many infectious diseases were described in North Africa in 18th-19th centuries by European travellers. Most of them were allegedly imported by new migrant populations coming from sub-Saharan, European or Middle East countries. Plague outbreaks have been described since the Black Death as diseases of the Mediterranean harbours. Charles Nicolle and his collaborators at the Pasteur Institute were witnesses to the extinction of plague and typhus fever in Tunisia. Both could be considered as endemo-epidemic diseases propagated by ancient nomad communities for centuries. Typhus was exported to other countries; plague was imported by Mediterranean travellers but also hid in unknown wild-animal reservoirs. The role of the bite of a rat's flea was not confirmed and the pneumonic form might have prevailed in the medieval North African cities. Association between plague, typhus, flu and other causes of immune deficiencies could explain the high morbidity and mortality caused by plague in the past. The authors comment the local history of plague at the light of the evolutionary laws of infectious disease proposed by Charles Nicolle in 1930.
PRECIPITATION CHEMISTRY OF MAGNESIUM SULFITE HYDRATES IN MAGNESIUM OXIDE SCRUBBING
The report gives results of laboratory studies defining the precipitation chemistry of MgSO3 hydrates. The results apply to the design of Mg-based scrubbing processes for SO2 removal from combustion flue gas. In Mg-based scrubbing processes, MgSO3 precipitates as either trihydrat...
Low level vapor verification of monomethyl hydrazine
NASA Technical Reports Server (NTRS)
Mehta, Narinder
1990-01-01
The vapor scrubbing system and the coulometric test procedure for the low level vapor verification of monomethyl hydrazine (MMH) are evaluated. Experimental data on precision, efficiency of the scrubbing liquid, instrument response, detection and reliable quantitation limits, stability of the vapor scrubbed solution, and interference were obtained to assess the applicability of the method for the low ppb level detection of the analyte vapor in air. The results indicated that the analyte vapor scrubbing system and the coulometric test procedure can be utilized for the quantitative detection of low ppb level vapor of MMH in air.
Large scale database scrubbing using object oriented software components.
Herting, R L; Barnes, M R
1998-01-01
Now that case managers, quality improvement teams, and researchers use medical databases extensively, the ability to share and disseminate such databases while maintaining patient confidentiality is paramount. A process called scrubbing addresses this problem by removing personally identifying information while keeping the integrity of the medical information intact. Scrubbing entire databases, containing multiple tables, requires that the implicit relationships between data elements in different tables of the database be maintained. To address this issue we developed DBScrub, a Java program that interfaces with any JDBC compliant database and scrubs the database while maintaining the implicit relationships within it. DBScrub uses a small number of highly configurable object-oriented software components to carry out the scrubbing. We describe the structure of these software components and how they maintain the implicit relationships within the database.
Concept-match medical data scrubbing. How pathology text can be used in research.
Berman, Jules J
2003-06-01
In the normal course of activity, pathologists create and archive immense data sets of scientifically valuable information. Researchers need pathology-based data sets, annotated with clinical information and linked to archived tissues, to discover and validate new diagnostic tests and therapies. Pathology records can be used for research purposes (without obtaining informed patient consent for each use of each record), provided the data are rendered harmless. Large data sets can be made harmless through 3 computational steps: (1) deidentification, the removal or modification of data fields that can be used to identify a patient (name, social security number, etc); (2) rendering the data ambiguous, ensuring that every data record in a public data set has a nonunique set of characterizing data; and (3) data scrubbing, the removal or transformation of words in free text that can be used to identify persons or that contain information that is incriminating or otherwise private. This article addresses the problem of data scrubbing. To design and implement a general algorithm that scrubs pathology free text, removing all identifying or private information. The Concept-Match algorithm steps through confidential text. When a medical term matching a standard nomenclature term is encountered, the term is replaced by a nomenclature code and a synonym for the original term. When a high-frequency "stop" word, such as a, an, the, or for, is encountered, it is left in place. When any other word is encountered, it is blocked and replaced by asterisks. This produces a scrubbed text. An open-source implementation of the algorithm is freely available. The Concept-Match scrub method transformed pathology free text into scrubbed output that preserved the sense of the original sentences, while it blocked terms that did not match terms found in the Unified Medical Language System (UMLS). The scrubbed product is safe, in the restricted sense that the output retains only standard medical terms. The software implementation scrubbed more than half a million surgical pathology report phrases in less than an hour. Computerized scrubbing can render the textual portion of a pathology report harmless for research purposes. Scrubbing and deidentification methods allow pathologists to create and use large pathology databases to conduct medical research.
Premaratna, Ranjan; Blanton, Lucas S; Samaraweera, Dilhar N; de Silva, G Nalika N; Chandrasena, Nilmini T G A; Walker, David H; de Silva, H J
2017-01-13
To date more than 20 antigenically distinct strains of Orientia tsutsugamushi (OT) reported within the tsutsugamushi triangle that cause an undifferentiated acute febrile illness in humans. Genotypic characterization of OT in different geographic regions or within the same country, is important in order to establish effective diagnostics, clinical management and to develop effective vaccines. Genetic and antigenic characterization of OT causing human disease in OT-endemic regions is not known for Sri Lanka. Adult patients and children who were admitted with an acute febrile illness and presumed to having acute scrub typhus based on presence of an eschar and other supporting clinical features were recruited. Eschar biopsies and buffy coat samples collected from patients who were confirmed having OT by IFA were further studied by real time PCR (Orientia 47 kD) and nested PCR (Orientia 56 kD) amplification. DNA sequences were obtained for 56 kD gene amplicons and phylogenetic comparisons were analyzed using currently available data in GenBank [Neucleotide substitution per 100 residues, 1000 Bootstrap Trials]. Twenty eschar biopsies (Location1,19, Location 2,1) and eight buffy coat samples (Location1,6, Location2,2) examined by real time PCR revealed Orientia amplicons in 16 samples. DNA sequences were obtained for the 56 kD gene amplicons in 12 eschars and 4 buffy coat samples. The genotypes of the Location1 samples revealed that, 7 exhibiting close homology with JP1 [distantly related to UT177 Thai (Karp related)], five had close homology with Kato strain, two had close homology with JGv and JG AF [Distantly related to Kawasaki M63383] and one had close homology with Gilliam strain. The Location 2 strain was closely related to Kuroki-Boryong L04956, the genotype which is distributed in far eastern Asia. Similar to other patients in the cohort this patient also had never travelled out of Sri Lanka. We observed all three main OT genotypes in Sri Lanka, and the majority fell into Thai Karp related clade. These results demonstrate great antigenic diversity of OT in the studied areas of Sri Lanka.
Kargupta, Roli; Hull, Garret J; Rood, Kyle D; Galloway, James; Matthews, Clinton F; Dale, Paul S; Sengupta, Shramik
2015-04-02
The Centers for Disease Control and Prevention's (CDC) National Healthcare Safety Network (NHSN) report published in 2009 shows that there were about 16,000 cases of surgical site infection (SSI) following ~ 850,000 operative procedures making SSI one of the most predominant infection amongst nosocomial infections. Preoperative skin preparation is a standard procedure utilized to prevent SSIs thereby improving patient outcomes and controlling associated healthcare costs. Multiple techniques/ products have been used for pre-operative skin preparation, like 2 step scrubbing and painting, 2 step scrubbing and drying, and 1 step painting with a drying time. However, currently used products require strict, time consuming and labor-intensive protocols that involve repeated mechanical scrubbing. It can be speculated that a product requiring a more facile protocol will increase compliance, thus promoting a reduction in SSIs. Hence, the antimicrobial efficacy of a spray-on foaming formulation containing Betadine (povidone-iodine aerosol foam) that can be administered with minimum effort is compared to that of an existing formulation/technique (Wet Skin Scrub). In vitro antimicrobial activities of (a) 5% Betadine delivered in aerosolized foam, (b) Wet Skin Scrub Prep Tray and (c) liquid Betadine are tested against three clinically representative microorganisms (S. aureus, S. epidermidis and P. aeruginosa,) on two surfaces (agar-gel on petri-dish and porcine skin). The log reduction/growth of the bacteria in each case is noted and ANOVA statistical analysis is used to establish the effectiveness of the antimicrobial agents, and compare their relative efficacies. With agar gel as the substrate, no growth of bacteria is observed for all the three formulations. With porcine skin as the substrate, the spray-on foam's performance was not statistically different from that of the Wet Skin Scrub Prep technique for the microorganisms tested. The povidone-iodine aerosolized foam could potentially serve as a non-labor intensive antimicrobial agent for surgical site preparation.
Typhus, yellow fever and Medicine in Mexico during the French intervention
Gerardo-Ramírez, Monserrat; Zavaleta-Castro, Jesús; Gómez-Quiroz, Luis Enrique
2018-01-01
French intervention in Mexico (1861-1867) is particularly full of episodes of patriotic heroism in terms of military, politic and, even, religious affairs, however this history is also rich in episodes related to diseases and the evolution of Mexican scientific medicine practice, epidemics such as typhus (nowadays knows as rickettsiosis), yellow fever, or cholera. Principally, this context outlined the Mexican history and influenced the course of the nation. The epidemics served as fertile land for the development of medicine science leading by prominent physicians, particularly by doctor Miguel Francisco Jiménez. Copyright: © 2018 SecretarÍa de Salud.
Lukin, E P; Mikhaĭlov, V V; Oleĭchik, V L; Solodiankin, A I
1996-01-01
On the basis of their earlier formula for modeling the possible development of the epidemic process of louse-borne exanthematous typhus the authors have calculated the probability of the development of such process for high indices (10 -- 12 % of convalescents with louse contamination rate among them reaching 20 -- 40 %) characterizing this process. The number of sources of this infection (primary patients), as well as the rate of increase and scale of louse contamination of the population, are of prime importance for the prognostication of the development of the epidemic.
Gazi, Michal; Caro-Gomez, Erika; Goez, Yenny; Cespedes, Maria A; Hidalgo, Marylin; Correa, Paula; Valbuena, Gustavo
2013-01-01
Rickettsia prowazekii has been tested for biological warfare due to the high mortality that it produces after aerosol transmission of very low numbers of rickettsiae. Epidemic typhus, the infection caused by these obligately intracellular bacteria, continues to be a threat because it is difficult to diagnose due to initial non-specific symptoms and the lack of commercial diagnostic tests that are sensitive and specific during the initial clinical presentation. A vaccine to prevent epidemic typhus would constitute an effective deterrent to the weaponization of R. prowazekii; however, an effective and safe vaccine is not currently available. Due to the cytoplasmic niche of Rickettsia, CD8(+) T-cells are critical effectors of immunity; however, the identification of antigens recognized by these cells has not been systematically addressed. To help close this gap, we designed an antigen discovery strategy that uses cell-based vaccination with antigen presenting cells expressing microbe's proteins targeted to the MHC class I presentation pathway. We report the use of this method to discover a protective T-cell rickettsial antigen, RP884, among a test subset of rickettsial proteins.
Two decades of change in a coastal scrub community: songbird responses to plant succession
Mary K. Chase; Aaron L. Holmes; Thomas Gardali; Grant Ballard; Geoffrey R. Geupel; Nadav Nur
2005-01-01
Coastal scrub habitats in California are threatened by habitat loss, fragmentation, and degradation. Local and statewide declines have been observed in several birds that breed in coastal scrub, most notably the California Gnatcatcher (Polioptila californica; Atwood 1993), but also include more common species such as the Whitecrowned Sparrow...
Alluvial Scrub Vegetation in Coastal Southern California
Ted L. Hanes; Richard D. Friesen; Kathy Keane
1989-01-01
Certain floodplain systems in southern California sustain a unique scrub vegetation rather than riparian woodlands due to a lack of perennial water. Alluvial scrub occurs on outwash fans and riverine deposits along the coastal side of major mountains of southern California. This vegetation type is adapted to severe floods and erosion, nutrient-poor substrates, and the...
77 FR 77037 - Procurement List; Additions
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-31
...-Compatible, 2'' x 8'' NSN: 7920-00-NIB-0545--Scrub Brush, Wire, Knuckle Guard, Long Handle, Ergonomic, 6'' x 1 1/8'', w/built-in scraper NSN: 7920-00-NIB-0547--Scrub Brush, Wire, Stainless, Ergonomic, 5'' NSN: 7920-00-NIB-0558--Scrub Brush, Wire, Black Tempered, Ergonomic, 5'' NSN: 7920-00-NIB-0563--Wire Brush...
40 CFR Appendix B to Part 425 - Modified Monier-Williams Method
Code of Federal Regulations, 2014 CFR
2014-07-01
... is removed by scrubbing the nitrogen gas stream in a pH 7 buffer solution. The sulfide gas is collected by passage through an alkaline hydrogen peroxide scrubbing solution in which it is oxidized to sulfate. Sulfate concentration in the scrubbing solution is determined by either EPA gravimetric test...
40 CFR Appendix B to Part 425 - Modified Monier-Williams Method
Code of Federal Regulations, 2013 CFR
2013-07-01
... is removed by scrubbing the nitrogen gas stream in a pH 7 buffer solution. The sulfide gas is collected by passage through an alkaline hydrogen peroxide scrubbing solution in which it is oxidized to sulfate. Sulfate concentration in the scrubbing solution is determined by either EPA gravimetric test...
77 FR 64326 - Procurement List; Proposed Additions and Deletions
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-19
...-Compatible, 2'' x 8''. NSN: 7920-00-NIB-0545--Scrub Brush, Wire, Knuckle Guard, Long Handle, Ergonomic, 6'' x 1 1/8'', w/built-in scraper. NSN: 7920-00-NIB-0547--Scrub Brush, Wire, Stainless, Ergonomic, 5''. NSN: 7920-00-NIB-0558--Scrub Brush, Wire, Black Tempered, Ergonomic, 5''. NSN: 7920-00-NIB-0563--Wire...
2009-03-07
Designated Areas lor Scrub Issue i : FHSI 2. I West ?. Cardiac Cath Lab> 4. Cardiology Radiology 5. Centralized Materiel Services 6. CCUs...Scrub Management System 37 BAMC Memo 52-2 4-. Neiirosnrgciy Clinic 15. Bum Tinuma Unit 46 Cinq Rullis -4". 9J V School -IS. Veterinary Clinic
Stature of sub-arctic birch in relation to growth rate, lifespan and tree form.
Jónsson, Thorbergur Hjalti
2004-11-01
Sub-arctic mountain birch Betula pubescens var. pumila communities in the North Atlantic region are of variable stature, ranging from prostrate scrubs to forests with trees up to 12 m high. Four hypotheses were tested, relating growth and population characteristics of sub-arctic birch woodland and scrub to tree stature; i.e. the variable stature of birch woods is due to differences in (1) the mean growth rate; (2) the age-related patterns of growth rate; (3) the life expectancy of stems; or (4) the tree form. A stratified random sample of 300 birch trees was drawn from the total population of indigenous birch woodlands and scrub in Iceland, yielding 286 valid sample genets. The population was divided into three sub-populations with dominant trees 0-2, 2-4 and 4-12 m tall, referred to as birch scrub, birch scrub-woodland and birch forest, respectively. Trees in the scrub population were of more contorted growth form than birch in the scrub-woodland and forest populations. Mean growth rates, mean age and median life expectancies increased significantly with sub-population of greater tree stature. At the population level, annual increment and longevity of birch stems was apparently interrelated as the stems in vigorously growing birch sub-populations had a longer life expectancy than those of slower growth. However, no difference was observed between sub-populations in age-related patterns of extension growth rate. The results were consistent with hypotheses (1), (3) and (4), but hypothesis (2) was rejected. Hence, mountain birch of more vigorous growth attains a greater stature than birch of lesser increment due to faster extension growth rate and a longer lifespan. In addition, the more contorted stem form of scrub populations contributes to their low stature.
Studies on Typhus and Spotted Fever.
1980-02-01
prowazekii-infected human somatic (fibroblast, endothelia)), but not chick, mouse or monkey , cells in culture: (a) intracellular antirickettsial action...that of the controls. No such effect on growth was apparent in CE cells, Nu E % o0 M Ŕ ZOO - .0 E 00 (1 CI - 4D W = .) C ~ o r- -!NBI Go !N 21501,,o o...human origin transformed or malignant cells, monkey primary or diploid and primary mouse embryo fibroblasts will permit expression of these effects to
Re-caching by Western scrub-jays (Aphelocoma californica) cannot be attributed to stress.
Thom, James M; Clayton, Nicola S
2013-01-01
Western scrub-jays (Aphelocoma californica) live double lives, storing food for the future while raiding the stores of other birds. One tactic scrub-jays employ to protect stores is "re-caching"-relocating caches out of sight of would-be thieves. Recent computational modelling work suggests that re-caching might be mediated not by complex cognition, but by a combination of memory failure and stress. The "Stress Model" asserts that re-caching is a manifestation of a general drive to cache, rather than a desire to protect existing stores. Here, we present evidence strongly contradicting the central assumption of these models: that stress drives caching, irrespective of social context. In Experiment (i), we replicate the finding that scrub-jays preferentially relocate food they were watched hiding. In Experiment (ii) we find no evidence that stress increases caching. In light of our results, we argue that the Stress Model cannot account for scrub-jay re-caching.
Cuzzubbo, Andrea J.; Vaughn, David W.; Nisalak, Ananda; Solomon, Tom; Kalayanarooj, Siripen; Aaskov, John; Dung, Nguyen Minh; Devine, Peter L.
1999-01-01
The performances of the MRL dengue fever virus immunoglobulin M (IgM) capture enzyme-linked immunosorbent assay (ELISA) and the PanBio Dengue Duo IgM capture and IgG capture ELISA were compared. Eighty sera from patients with dengue virus infections, 24 sera from patients with Japanese encephalitis (JE), and 78 sera from patients with nonflavivirus infections, such as malaria, typhoid, leptospirosis, and scrub typhus, were used. The MRL test showed superior sensitivity for dengue virus infections (94 versus 89%), while the PanBio test showed superior specificity for JE (79 versus 25%) and other infections (100 versus 91%). The PanBio ELISA showed better overall performance, as assessed by the sum of sensitivity and specificity (F value). When dengue virus and nonflavivirus infections were compared, F values of 189 and 185 were obtained for the PanBio and MRL tests, respectively, while when dengue virus infections and JE were compared, F values of 168 and 119 were obtained. The results obtained with individual sera in the PanBio and MRL IgM ELISAs showed good correlation, but this analysis revealed that the cutoff value of the MRL test was set well below that of the PanBio test. Comparing the sensitivity and specificity of the tests at different cutoff values (receiver-operator analysis) revealed that the MRL and PanBio IgM ELISAs performed similarly in distinguishing dengue virus from nonflavivirus infections, although the PanBio IgM ELISA showed significantly better distinction between dengue virus infections and JE. The implications of these findings for the laboratory diagnosis of dengue are discussed. PMID:10473522
Gorvel, Laurent; Textoris, Julien; Banchereau, Romain; Ben Amara, Amira; Tantibhedhyangkul, Wiwit; von Bargen, Kristin; Ka, Mignane B; Capo, Christian; Ghigo, Eric; Gorvel, Jean-Pierre; Mege, Jean-Louis
2014-01-01
Dendritic cells (DCs) orchestrate host defenses against microorganisms. In infectious diseases due to intracellular bacteria, the inefficiency of the immune system to eradicate microorganisms has been attributed to the hijacking of DC functions. In this study, we selected intracellular bacterial pathogens with distinct lifestyles and explored the responses of monocyte-derived DCs (moDCs). Using lipopolysaccharide as a control, we found that Orientia tsutsugamushi, the causative agent of scrub typhus that survives in the cytosol of target cells, induced moDC maturation, as assessed by decreased endocytosis activity, the ability to induce lymphocyte proliferation and the membrane expression of phenotypic markers. In contrast, Coxiella burnetii, the agent of Q fever, and Brucella abortus, the agent of brucellosis, both of which reside in vacuolar compartments, only partly induced the maturation of moDCs, as demonstrated by a phenotypic analysis. To analyze the mechanisms used by C. burnetii and B. abortus to alter moDC activation, we performed microarray and found that C. burnetii and B. abortus induced a specific signature consisting of TLR4, TLR3, STAT1 and interferon response genes. These genes were down-modulated in response to C. burnetii and B. abortus but up-modulated in moDCs activated by lipopolysaccharide and O. tsutsugamushi. This transcriptional alteration was associated with the defective interferon-β production. This study demonstrates that intracellular bacteria specifically affect moDC responses and emphasizes how C. burnetii and B. abortus interfere with moDC activation and the antimicrobial immune response. We believe that comparing infection by several bacterial species may be useful for defining new pathways and biomarkers and for developing new treatment strategies.
Halder, Ajay; Jose, Ruby; Vijayselvi, Reeta
2014-01-01
Preceding the use of World Health Organization (WHO) near-miss approach in our institute for the surveillance of Severe Maternal Outcome (SMO), we pilot-tested the tool on maternal death cases that took place over the last 10 years in order to establish its feasibility and usefulness at the institutional level. This was a retrospective review of maternal deaths in Christian Medical College Vellore, India, over a decade. Cases were recorded and analyzed using the WHO near-miss tool. The International Classification of Diseases, 10(th) Revision was used to define and classify maternal mortality. There were 98,139 total births and 212 recorded maternal deaths. Direct causes of mortality constituted 46.96% of total maternal deaths, indirect causes constituted 51.40%, and unknown cases constituted 1.9%. Nonobstetrical cause (48.11%) is the single largest group. Infections (19.8%) other than puerperal sepsis remain an important group, with pulmonary tuberculosis, scrub typhus, and malaria being the leading ones. According to the WHO near-miss criteria, cardiovascular and respiratory dysfunctions are the most frequent organ dysfunctions. Incidence of coagulation dysfunction is seen highest in obstetrical hemorrhage (64%). All women who died had at least one organ dysfunction; 90.54% mothers had two- and 38.52% had four- or more organ involvement. The screening questions of the WHO near-miss tool are particularly instrumental in obtaining a comprehensive assessment of the problem beyond the International Classification of Diseases-Maternal Mortality and establish the need for laboratory-based identification of organ dysfunctions and prompt availability of critical care facilities. The process indicators, on the other hand, inquire about the basic interventions that are more or less widely practiced and therefore give no added information at the institutional level.
Frances, S P; Watcharapichat, P; Phulsuksombati, D
2001-01-01
Vertical transmission of Orientia tsutsugamushi (Hayashi), the etiologic agent for scrub typhus, was studied in two lines of naturally infected Leptotrombidium deliense Walch. In one line of mites originating from a single adult (V3M), the rate of filial transmission was 100% for the first two laboratory generations, but declined to 86.6% in the third laboratory generation. The vertical infection rate in this line of mites was 100% for the parental generation, but declined to 95.6% for the F1 generation and 88.6% for F2. The transmission of O. tsutsugamushi in another line of L. deliense (V3F) was less efficient than mites originating from V3M. In the initial laboratory generation of V3F a filial transmission rate of 100% was recorded. However, none of the F2 generation of this line transmitted rickettsiae to mice (Mus musculus L.), resulting in a filial transmission rate of 0%. Transmission of O. tsutsugamushi to mice by progeny from cohort larvae originally from the same adult (V3F) was also studied in the laboratory and these were found to be relatively poor transmitters of rickettsiae. The filial infection rate of F2 larvae was 60%, F3 was 88.8%, and F4 was 55.9%. The biology of infected L. deliense was studied and compared with uninfected mites reared under the same laboratory conditions. The results showed that infected female L. deliense laid approximately the same or more eggs as uninfected adults. The rate of development of the progeny of infected L. deliense was not significantly different from uninfected mites.
[Comparative study of the cost/effectiveness of surgical wash with various antiseptics].
Tapia-Jurado, Jesús; Reyes-Arellano, Wulfrano; García-García, Juan José; Jiménez-Corona, José Luis; Peña-Jiménez, Carmen Magdalena; León-Mancilla, Benjamín
2011-01-01
"Surgical scrub" of the hands and arms is a fundamental procedure for reducing infection risk. We undertook this study in order to compare different antiseptics and their microbicidal effects, costs and times of the procedures. Thirty students followed the surgical scrub procedure using benzalkonium chloride. Seven days later the students used povidone-iodine and, 7 days after that, they used chlorhexidine/alcohol. After the surgical scrub, cultures were obtained from the palms of their hands and from their nail beds. The students wore sterile gloves, which were removed 30 min later to obtain new cultures from the same sites. The cost of the products was calculated in Mexican pesos and the time of each procedure was measured in minutes. There was a statistically significant difference in the number of colony-forming units (CFUs). The number of CFUs was lower in the groups of students who used chlorhexidine/alcohol and povidone-iodine as compared to the benzalkonium chloride group. There was no difference between chlorhexidine/alcohol and povidone-iodine. Costs were higher for povidone-iodine and benzalkonium chloride compared to chlorhexidine/alcohol. Procedure times were similar with povidone-iodine and benzalkonium chloride but the time was reduced approximately five times when using chlorhexidine/alcohol. It is a proven fact that the lack of surgical scrub favors wound infections, longer hospital stays and increased costs. Therefore, further studies are needed to determine the best antiseptic according to cost/benefit. Chlorhexidine/alcohol proved to be the superior antiseptic in terms of cost/benefit compared to povidone-iodine and benzalkonium chloride.
Trace Contaminant Testing with the Orion Atmosphere Revitalization Technology
NASA Technical Reports Server (NTRS)
Button, Amy Lin; Sweterlitsch, Jeffrey; Broerman, Craig
2009-01-01
Every spacecraft atmosphere contains trace contaminants resulting from offgassing by cabin materials and human passengers. An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). Part of the risk mitigation effort for this new technology is the study of how atmospheric trace contaminants will affect and be affected by the technology. One particular area of concern is ammonia, which, in addition to the normal spacecraft sources, can also be off-gassed by the amine-based sorbent. In the first half of 2009, tests were performed with typical cabin atmosphere levels of five of the most common trace gases, most of which had not yet been tested with this technology. A subscale sample of the sorbent was exposed to each of the chemicals mixed into a stream of moist, CO2-laden air, and the CO2 adsorption capacity of the sorbent was compared before and after the exposure. After these typical-concentration chemicals were proven to have negligible effect on the subscale sample, tests proceeded on a full-scale test article in a sealed chamber with a suite of eleven contaminants. To isolate the effects of various test rig components, several extended-duration tests were run: without injection or scrubbing, with injection and without scrubbing, with injection and scrubbing by both the test article and dedicated trace contaminant filters, and with injection and scrubbing by only the test article. The high-level results of both the subscale and full-scale tests are examined in this paper.