Parasite infection alters nitrogen cycling at the ecosystem scale.

PubMed

Mischler, John; Johnson, Pieter T J; McKenzie, Valerie J; Townsend, Alan R

2016-05-01

Despite growing evidence that parasites often alter nutrient flows through their hosts and can comprise a substantial amount of biomass in many systems, whether endemic parasites influence ecosystem nutrient cycling, and which nutrient pathways may be important, remains conjectural. A framework to evaluate how endemic parasites alter nutrient cycling across varied ecosystems requires an understanding of the following: (i) parasite effects on host nutrient excretion; (ii) ecosystem nutrient limitation; (iii) effects of parasite abundance, host density, host functional role and host excretion rate on nutrient flows; and (iv) how this infection-induced nutrient flux compares to other pools and fluxes. Pathogens that significantly increase the availability of a limiting nutrient within an ecosystem should produce a measurable ecosystem-scale response. Here, we combined field-derived estimates of trematode parasite infections in aquatic snails with measurements of snail excretion and tissue stoichiometry to show that parasites are capable of altering nutrient excretion in their intermediate host snails (dominant grazers). We integrated laboratory measurements of host nitrogen excretion with field-based estimates of infection in an ecosystem model and compared these fluxes to other pools and fluxes of nitrogen as measured in the field. Eighteen nitrogen-limited ponds were examined to determine whether infection had a measurable effect on ecosystem-scale nitrogen cycling. Because of their low nitrogen content and high demand for host carbon, parasites accelerated the rate at which infected hosts excreted nitrogen to the water column in a dose-response manner, thereby shifting nutrient stoichiometry and availability at the ecosystem scale. Infection-enhanced fluxes of dissolved inorganic nitrogen were similar to other commonly important environmental sources of bioavailable nitrogen to the system. Additional field measurements within nitrogen-limited ponds indicated that

The magnitude and risk factors of intestinal parasitic infection in relation to Human Immunodeficiency Virus infection and immune status, at ALERT Hospital, Addis Ababa, Ethiopia.

PubMed

Taye, Biruhalem; Desta, Kassu; Ejigu, Selamawit; Dori, Geme Urge

2014-06-01

Human Immunodeficiency Virus (HIV) and intestinal parasitic infections are among the main health problems in developing countries like Ethiopia. Particularly, co-infections of these diseases would worsen the progression of HIV to Acquired Immunodeficiency Syndrome (AIDS). The purpose of this study was to determine the magnitude and risk factors for intestinal parasites in relation to HIV infection and immune status. The study was conducted in (1) HIV positive on antiretroviral therapy (ART) and (2) ART naïve HIV positive patients, and (3) HIV-negative individuals, at All African Leprosy and Tuberculosis (TB) Eradication and Rehabilitation Training Center (ALERT) hospital in Addis Ababa, Ethiopia. Study participants were interviewed using structured questionnaires to obtain socio-demographic characteristics and assess risk factors associated with intestinal parasitic infection. Intestinal parasites were identified from fecal samples by direct wet mount, formol ether concentration, and modified Ziehl-Neelsen staining techniques. The immune status was assessed by measuring whole blood CD4 T-cell count. The overall magnitude of intestinal parasite was 35.08%. This proportion was different among study groups with 39.2% (69/176), 38.83% (40/103) and 27.14% (38/140) in ART naïve HIV positives patients, in HIV negatives, and in HIV positive on ART patients respectively. HIV positive patients on ART had significantly lower magnitude of intestinal parasitic infection compared to HIV negative individuals. Intestinal helminths were significantly lower in HIV positive on ART and ART naïve patients than HIV negatives. Low monthly income, and being married, divorced or widowed were among the socio-demographic characteristics associated with intestinal parasitic infection. No association was observed between the magnitude of intestinal parasites and CD4 T-cell count. However, Cryptosporidium parvum, and Isospora belli were exclusively identified in individuals with CD4 T

Intestinal Parasitic Infections in HIV Infected and Non-Infected Patients in a Low HIV Prevalence Region, West-Cameroon

PubMed Central

Nkenfou, Céline Nguefeu; Nana, Christelle Tafou; Payne, Vincent Khan

2013-01-01

The magnitude of intestinal parasitic infection in acquired immunodeficiency syndrome patients requires careful consideration in the developing world where poor nutrition is associated with poor hygiene and several tropical diseases. However, there have been very few studies addressing this issue in Cameroon. This study was conducted to determine the prevalence of intestinal parasitosis in HIV/AIDS patients in Dschang -Cameroon. Stool and blood specimens from HIV/AIDS patients and control group were screened respectively for intestinal parasites and for HIV antibodies. Intestinal parasites were identified using direct microscopy, formalin-ether concentration and Ziehl Neelsen methods. Out of 396 participants recruited among patients consulting at hospital, 42 (10.6%) were HIV positive, thirty of them treatment naïve. The overall prevalence of intestinal parasites was 14.64%. Out of 42 HIV/AIDS patients, 59.5% (25/42) were infected with intestinal parasites, while only 9.32% (33/354) of the HIV negative patients were infected with intestinal parasites. The parasites detected in our study population included Crystosporidium parvum (2.53%), Entamoeba histolytica (7.52%), Entamoeba coli (4.04%), Giardia lamblia (0.25%), Trichuris trichura (0.25%), Strongyloides stercoralis (0.25%) and Taenia spp. (0.25%). In the HIV infected group, Crystosporidium parvum (19.04%), Entamoeba histolytica (19.04%), Entamoeba coli (21.42%), Giardia lamblia (2.38%), Strongyloides stercoralis (0.25%) and Taenia spp. (0.25%) were found. Crystosporidium parvum was found to be significantly higher in HIV/AIDS patients than in controls (P<0.05). Multivariate analysis showed that the HIV status and the quality of water were the major risk factors for intestinal parasitosis. Routine examinations of stool samples for parasites would significantly benefit the HIV patients by contributing in reducing morbidity and improving the efficiency of antiretroviral treatment. Even after the introduction of

Wild Anopheles funestus mosquito genotypes are permissive for infection with the rodent malaria parasite, Plasmodium berghei.

PubMed

Xu, Jiannong; Hillyer, Julián F; Coulibaly, Boubacar; Sacko, Madjou; Dao, Adama; Niaré, Oumou; Riehle, Michelle M; Traoré, Sekou F; Vernick, Kenneth D

2013-01-01

Malaria parasites undergo complex developmental transitions within the mosquito vector. A commonly used laboratory model for studies of mosquito-malaria interaction is the rodent parasite, P. berghei. Anopheles funestus is a major malaria vector in sub-Saharan Africa but has received less attention than the sympatric species, Anopheles gambiae. The imminent completion of the A. funestus genome sequence will provide currently lacking molecular tools to describe malaria parasite interactions in this mosquito, but previous reports suggested that A. funestus is not permissive for P. berghei development. An A. funestus population was generated in the laboratory by capturing female wild mosquitoes in Mali, allowing them to oviposit, and rearing the eggs to adults. These F1 progeny of wild mosquitoes were allowed to feed on mice infected with a fluorescent P. berghei strain. Fluorescence microscopy was used to track parasite development inside the mosquito, salivary gland sporozoites were tested for infectivity to mice, and parasite development in A. funestus was compared to A. gambiae. P. berghei oocysts were detectable on A. funestus midguts by 7 days post-infection. By 18-20 days post-infection, sporozoites had invaded the median and distal lateral lobes of the salivary glands, and hemocoel sporozoites were observed in the hemolymph. Mosquitoes were capable of infecting mice via bite, demonstrating that A. funestus supports the complete life cycle of P. berghei. In a random sample of wild mosquito genotypes, A. funestus prevalence of infection and the characteristics of parasite development were similar to that observed in A. gambiae-P. berghei infections. The data presented in this study establish an experimental laboratory model for Plasmodium infection of A. funestus, an important vector of human malaria. Studying A. funestus-Plasmodium interactions is now feasible in a laboratory setting. This information lays the groundwork for exploitation of the awaited genome

Infecting Pacific Herring with Ichthyophonus sp. in the laboratory

USGS Publications Warehouse

Hershberger, Paul; Hart, Lucas; Mackenzie, Ashley; Yanney, M.L.; Conway, Carla M.; Elliott, Diane G.

2015-01-01

The protistan parasite Ichthyophonus sp. occurs in coastal populations of Pacific Herring Clupea pallasii throughout the northeast Pacific region, but the route(s) by which these planktivorous fish become infected is unknown. Several methods for establishing Ichthyophonus infections in laboratory challenges were examined. Infections were most effectively established after intraperitoneal (IP) injections with suspended parasite isolates from culture or after repeated feedings with infected fish tissues. Among groups that were offered the infected tissues, infection prevalence was greater after multiple feedings (65%) than after a single feeding (5%). Additionally, among groups that were exposed to parasite suspensions prepared from culture isolates, infection prevalence was greater after exposure by IP injection (74%) than after exposure via gastric intubation (12%); the flushing of parasite suspensions over the gills did not lead to infections in any of the experimental fish. Although the consumption of infected fish tissues is unlikely to be the primary route of Ichthyophonus sp. transmission in wild populations of Pacific Herring, this route may contribute to abnormally high infection prevalence in areas where juveniles have access to infected offal.

No effect of a parasite on reproduction in stickleback males: a laboratory artefact?

PubMed

Candolin, U; Voigt, H R

2001-04-01

Experiments are often carried out in the laboratory under artificial conditions. Although this can control for confounding factors, it may eliminate important factors that under natural conditions mediate the interaction under investigation. Here, we show that different results can be gained in the field and in the laboratory regarding host-parasite interaction. In the field, courting three-spined stickleback males, Gasterosteus aculeatus, were less often infected with plerocercoids of a cestode tapeworm, Schistocephalus solidus, than shoaling males. However, when a random sample of males was allowed to nest and court females in individual aquaria in the laboratory, both uninfected and infected males built nests and courted females. Moreover, while the few infected males that courted females in the field expressed less red nuptial coloration than uninfected courting males, there was no difference in redness between infected and uninfected males in the laboratory. We argue that the different results gained in the field and in the laboratory are due to differences in the cost of reproduction, due to differences in the resource pool of the males. The favourable conditions in the laboratory exclude factors such as predation risk, social interactions, and fluctuating environmental conditions that may use up resources in the field and mediate the effect of the parasite.

Glomerulopathy Associated with Parasitic Infections

PubMed Central

van Velthuysen, M.-L. F.; Florquin, S.

2000-01-01

Although parasitic infections do not usually present with disturbance in renal function, glomerular lesions can be seen in most of these infections. The glomerular lesions observed in parasitic infections cover the whole range of glomerular lesions known, but most of them are proliferative. Little is known of the exact pathogenic mechanisms. In this review, we try to explain the glomerular lesions associated with parasitic infections in terms of the specific immunologic events observed during these diseases against the background of recent developments in the general knowledge of the pathogenesis of glomerular disease. PMID:10627491

Parasitic infections of the external eye.

PubMed

Pahuja, Shivani; Puranik, Charuta; Jelliti, Bechir; Khairallah, Moncef; Sangwan, Virender S

2013-08-01

To review the published literature on parasitic infections of external eye. Published articles and case reports on parasitic infections of external eye were reviewed and relevant information was collected. Parasitic infections of the eye are rare. However, being more commonly seen in developing nations, they require active measures for screening, diagnosis, and therapy. Parasites of importance causing external ocular disease are protozoan parasites, such as Leishmania; metazoans, such as nematodes (roundworms), cestodes (tapeworms), and trematodes (flatworms); or ectoparasites, such as Phthirus pubis and Demodex.

Resist Globally, Infect Locally: A Transcontinental Test of Adaptation by Stickleback and Their Tapeworm Parasite.

PubMed

Weber, Jesse N; Kalbe, Martin; Shim, Kum Chuan; Erin, Noémie I; Steinel, Natalie C; Ma, Lei; Bolnick, Daniel I

2017-01-01

Parasite infections are a product of both ecological processes affecting host-parasite encounter rates and evolutionary dynamics affecting host susceptibility. However, few studies examine natural infection variation from both ecological and evolutionary perspectives. Here, we describe the ecological and evolutionary factors generating variation in infection rates by a tapeworm (Schistocephalus solidus) in a vertebrate host, the threespine stickleback (Gasterosteus aculeatus). To explore ecological aspects of infection, we measured tapeworm prevalence in Canadian stickleback inhabiting two distinct environments: marine and freshwater. Consistent with ecological control of infection, the tapeworm is very rare in marine environments, even though marine fish are highly susceptible. Conversely, commonly infected freshwater stickleback exhibit substantial resistance in controlled laboratory trials, suggesting that high exposure risk overwhelms their recently evolved resistance. We also tested for parasite adaptation to its host by performing transcontinental reciprocal infections, using stickleback and tapeworm populations from Europe and western Canada. More infections occurred in same-continent host-parasite combinations, indicating parasite "local" adaptation, at least on the scale of continents. However, the recently evolved immunity of freshwater hosts applies to both local and foreign parasites. The pattern of adaptation described here is not wholly compatible with either of the common models of host-parasite coevolution (i.e., matching infection or targeted recognition). Instead, we propose a hybrid, eco-evolutionary model to explain the remarkable pattern of global host resistance and local parasite infectivity.

Neglected parasitic infections in the United States: toxocariasis.

PubMed

Woodhall, Dana M; Eberhard, Mark L; Parise, Monica E

2014-05-01

Toxocariasis is a preventable parasitic disease that is caused by the dog and cat roundworms Toxocara cani and T. cati, respectively. Humans become infected when they accidently ingest infectious Toxocara eggs commonly found in contaminated soil; children are most often affected. Clinical manifestations of Toxocara infection in humans include ocular toxocariasis and visceral toxocariasis. Although infection with Toxocara can cause devastating disease, the burden of toxocariasis in the United States population remains unknown. In addition, risk factors for acquiring infection need to be better defined, and research needs to be conducted to better understand the pathophysiology and clinical course of toxocariasis. Development of diagnostic tests would enable clinicians to detect active infection, and determination of optimal drug regiments would ensure patients were appropriately treated. Addressing these public health gaps is necessary to understand and address the impact of toxocariasis in the United States.

Screening for parasite infections in immigrant children from low-income countries.

PubMed

Belhassen-García, Moncef; Pardo-Lledías, Javier; Pérez Del Villar, Luis; Velasco-Tirado, Virginia; Siller Ruiz, María; Cordero-Sánchez, Miguel; Vicente, Belen; Hernández Egido, Sara; Muñoz Bellido, Juan Luis; Muro, Antonio

2017-01-01

In Spain, minors represent approximately 20% of the immigration flow. Many of these immigrants come from countries in the tropics and sub-tropics where intestinal parasitic infections caused by helminths and protozoa are one of the major causes of human disease. The main objective of the present work was to describe parasite infections in a group of immigrant children. A prospective evaluation was performed in 373 minors from Sub-Saharan Africa, North Africa, and Latin America. Details were collected from the medical records and physical examination. Urine, stool and peripheral blood samples were obtained for serological and routine laboratory tests. Direct and indirect parasitological tests were also performed. At least 1 parasitic disease was diagnosed in 176 (47.1%) immigrant children, while 77 (20.6%) minors were infected with two or more parasites. The number of parasites was highest in children from Sub-Saharan Africa compared with the rest of the areas of origin (p<.001), and in children from urban areas compared with those from rural areas (OR 1.27 [1.059-1.552], p=.011). The most frequent causes of multiple parasite infection were filariasis plus strongyloidiasis and filariasis plus schistosomiasis. Intestinal parasite infection was diagnosed in 38 cases (13.8%). Logistic regression analysis revealed that for each month of stay, the probability of a positive finding in the stool sample decreased by 0.02% [β=-0.020, (p=.07)]. The high infection rates of parasite diseases in immigrant children point to the need for screening protocols for certain infectious diseases in these children according to their country of origin and their length of residence in Spain. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Risk Factors Associated with Parasitic Infection Among Municipality Solid-Waste Workers in an Egyptian Community.

PubMed

Eassa, Safaa M; El-Wahab, Ekram W Abd; Lotfi, Sameh E; El Masry, Sanaa A; Shatat, Hanan Z; Kotkat, Amira M

2016-04-01

Solid-waste management is associated with several health hazards, particularly parasitic infection. The objective of the study was to determine the association between risk factors and the occurrence of intestinal parasitic infections (potentially pathogenic) among municipal waste collectors in Alexandria, Egypt. A cross-sectional survey was conducted in the main municipality company in Alexandria. A total of 346 municipality solid-waste workers (MSWWs) was interviewed using an in-depth questionnaire. The type of parasitic infections among waste handlers was determined using formol-ether concentration and modified Ziehl-Neelsen technique. About half of the workers were infected with parasites. The profile of parasitic infection revealed 12 parasitic species. These were comprised of the following helminths: Schistosoma mansoni (13.3%), Enterobius vermicularis (1.7%), Ascaris lumbricoides (1.4%), and Hymenolepis nana ova (0.6%). Among protozoa were pathogenic Entamoeba histolytica (3.2%), Giardia intestinalis (2.9%), nonpathogenic protozoa such as Entamoeba coli (1.7%), and potentially pathogenic or opportunistic ones as Cryptosporidium (23.4%), Microsporidia (20.25%), Cyclospora (2.0%), Blastocystis hominis (1.7%), and Cystoisospora belli (1.2%). About 1.4% of MSWWs have pediculosis and phthiriasis in their scalp and eyelashes respectively. Risk factors for infection were associated with direct exposure to solid fecal waste (odds ratio [OR] = 1.8, confidence interval [CI] = 1.1-3.0) and occupational activities that allowed for direct exposure to solid fecal waste (OR = 2.3, CI = 1.4-4.0). Logistic regression model has revealed that educational level and residence were the factors that contribute to parasitic infection among MSWWs (P < 0.05). MSWWs are at high risk of acquiring parasitic infections. Data of the present study highlighted the need for greater biomonitoring of MSWWs and the improvement of environmental conditions and health care in such marginalized

Helminth Parasites Alter Protection against Plasmodium Infection

PubMed Central

Salazar-Castañon, Víctor H.; Legorreta-Herrera, Martha

2014-01-01

More than one-third of the world's population is infected with one or more helminthic parasites. Helminth infections are prevalent throughout tropical and subtropical regions where malaria pathogens are transmitted. Malaria is the most widespread and deadliest parasitic disease. The severity of the disease is strongly related to parasite density and the host's immune responses. Furthermore, coinfections between both parasites occur frequently. However, little is known regarding how concomitant infection with helminths and Plasmodium affects the host's immune response. Helminthic infections are frequently massive, chronic, and strong inductors of a Th2-type response. This implies that infection by such parasites could alter the host's susceptibility to subsequent infections by Plasmodium. There are a number of reports on the interactions between helminths and Plasmodium; in some, the burden of Plasmodium parasites increased, but others reported a reduction in the parasite. This review focuses on explaining many of these discrepancies regarding helminth-Plasmodium coinfections in terms of the effects that helminths have on the immune system. In particular, it focuses on helminth-induced immunosuppression and the effects of cytokines controlling polarization toward the Th1 or Th2 arms of the immune response. PMID:25276830

Helminth parasites alter protection against Plasmodium infection.

PubMed

Salazar-Castañon, Víctor H; Legorreta-Herrera, Martha; Rodriguez-Sosa, Miriam

2014-01-01

More than one-third of the world's population is infected with one or more helminthic parasites. Helminth infections are prevalent throughout tropical and subtropical regions where malaria pathogens are transmitted. Malaria is the most widespread and deadliest parasitic disease. The severity of the disease is strongly related to parasite density and the host's immune responses. Furthermore, coinfections between both parasites occur frequently. However, little is known regarding how concomitant infection with helminths and Plasmodium affects the host's immune response. Helminthic infections are frequently massive, chronic, and strong inductors of a Th2-type response. This implies that infection by such parasites could alter the host's susceptibility to subsequent infections by Plasmodium. There are a number of reports on the interactions between helminths and Plasmodium; in some, the burden of Plasmodium parasites increased, but others reported a reduction in the parasite. This review focuses on explaining many of these discrepancies regarding helminth-Plasmodium coinfections in terms of the effects that helminths have on the immune system. In particular, it focuses on helminth-induced immunosuppression and the effects of cytokines controlling polarization toward the Th1 or Th2 arms of the immune response.

Neglected Parasitic Infections in the United States: Toxocariasis

PubMed Central

Woodhall, Dana M.; Eberhard, Mark L.; Parise, Monica E.

2014-01-01

Toxocariasis is a preventable parasitic disease that is caused by the dog and cat roundworms Toxocara cani and T. cati, respectively. Humans become infected when they accidently ingest infectious Toxocara eggs commonly found in contaminated soil; children are most often affected. Clinical manifestations of Toxocara infection in humans include ocular toxocariasis and visceral toxocariasis. Although infection with Toxocara can cause devastating disease, the burden of toxocariasis in the United States population remains unknown. In addition, risk factors for acquiring infection need to be better defined, and research needs to be conducted to better understand the pathophysiology and clinical course of toxocariasis. Development of diagnostic tests would enable clinicians to detect active infection, and determination of optimal drug regiments would ensure patients were appropriately treated. Addressing these public health gaps is necessary to understand and address the impact of toxocariasis in the United States. PMID:24808249

Naturally acquired bovine besnoitiosis: Differential distribution of parasites in the skin of chronically infected cattle.

PubMed

Schares, G; Langenmayer, M C; Majzoub-Altweck, M; Scharr, J C; Gentile, A; Maksimov, A; Schares, S; Conraths, F J; Gollnick, N S

2016-01-30

Bovine besnoitiosis is caused by Besnoitia besnoiti, an apicomplexan parasite closely related to Toxoplasma gondii and Neospora caninum. In the acute stage of besnoitiosis, cattle suffer from pyrexia, swollen lymph nodes, anorexia and subcutaneous edema. In the chronic stage, tissue cysts are formed in a variety of tissues including the skin. Knowledge about the distribution of tissue cysts of different parts of the skin of infected animals is scarce. Four chronically infected cattle were euthanized and skin samples were taken from a total of 77 standardized cutaneous locations per animal. Portions of the dermis were taken, from which DNA was extracted and examined by real-time PCR. Cycle of transition (Ct) values reflecting the amount of parasite DNA in the samples were determined. For statistical analysis, samples were attributed to 11 larger skin regions ('OuterHindlegDistal', 'Rump, ForelegMiddle', 'NoseFrontEars', 'CheekEye', 'SideLowerPart', 'ForelegDistal', 'SideUpperPart', 'LegsInner', 'VentralHeadNeck', 'DorsalNeckWithersBackTail'). While all samples revealed a positive result in three female cattle, only 63.6% (49/77) of the samples of a bull showed positive results. For statistical analysis, a Ct value of 45 was assumed for samples with a negative result. The dams showed median Ct values of 16.1, 17.5 and 19.4, while in skin samples of the bull a median Ct value of 37.6 was observed. To determine the differences in DNA concentrations between different locations of the skin of the animals, a relative Ct (relCt) was determined by subtracting for each animal indv the MedianCtindv from each sample Ct. Analyses of the relCt values showed that the highest relative parasite DNA concentrations were observed in the categories 'OuterHindlegDistal', 'Rump', 'ForelegMiddle' and 'NoseFrontEars'. The relCt values in these categories differed statistically significantly from those determined for the categories 'VentralHeadNeck' and 'DorsalNeckWithersBackTail'. The

Practical parasitology courses and infection with intestinal parasites in students.

PubMed

Fallahi, Sh; Rostami, A; Mohammadi, M; Ebrahimzadeh, F; Pournia, Y

2016-01-01

Students who are working in research or educational laboratories of parasitology, as well as health care workers providing care for patients, are at the risk of becoming infected with parasites through accidental exposure. The main purpose of this study was to identify potential positive cases of intestinal parasitic infections among students who took practical parasitology courses compared with students who did not take any practical parasitology courses in Lorestan University of Medical Sciences, Khorramabad, Iran, in 2013-2014. A total of 310 subjects from various majors were invited to voluntarily participate in the study. Various demographic data were collected using questionnaires. Three stool samples were collected from each individual on alternate days. Saline wet mounts (SWM), formalin-ether sedimentation test (FEST), Sheather floatation test (SHFT) and trichrome and modified Ziehl-Neelsen staining methods were used to diagnose the presence of intestinal parasites. The prevalence rate of intestinal parasites (IPs) among the students was 11.93%. There was a significant difference between majors in the infection with IPs (P<0.05). The most frequently observed IPs were Blastocystis hominis (4.51%) and Giardia intestinalis (3.54%). The results of this study showed that the transmission of pathogenic parasites in the educational course of practical parasitology could occur and must be taken into careful consideration. Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Syphacia obvelata (Nematode, Oxyuridae) infecting laboratory mice Mus musculus (Rodentia, Muridae): phylogeny and host-parasite relationship.

PubMed

Abdel-Gaber, Rewaida

2016-03-01

Syphacia obvelata is a pinworm nematode parasite infecting man and laboratory animals in high abundance. This parasitological study was carried out during the period of March 2014-February 2015 to investigate the helminth parasites infecting the laboratory mice Mus musculus in the Animal House at Cairo University, Egypt. The prevalence of S. obvelata in M. musculus was 75.0 %. The extent of infection with S. obvelata is analyzed according to the sex of the host mice. It was shown that the prevalence of male infection was greater than female worms. Morphological characterization revealed that the present Oxyurid species possesses a rounded cephalic end with less developed lips, esophagus divided into cylindrical corpus, and globular bulb supported internally with valvular apparatus; three mamelons are located at the ventral surface with a single chitinized spicule and a gubernaculum provided with an accessory hook in males, and ovijector apparatus opens ventrally by the vulva surrounded by protruded lips in female worms. Body of the male was 0.623-1.130 (0.830 ± 0.11) mm long and 0.092-0.130 (0.110 ± 0.01) mm wide; the esophagus was 0.164-0.280 (0.210 ± 0.01) mm long; the nerve ring and excretory pore are located at 0.035-0.132 (0.073 ± 0.01) and 0.087-0.191 (0.145 ± 0.01) mm from the anterior end, respectively, while the female measured 2.930-4.650 (3.540 ± 0.1) mm long and 0.120-0.232 (0.156 ± 0.001) mm wide; the esophagus was 0.213-0.410 (0.342 ± 0.01) mm long; the nerve ring, excretory pore, and vulval opening are located at 0.026-0.157 (0.121 ± 0.01), 0.134-0.243 (0.195 ± 0.01), and 0.323-0.632 (0.546 ± 0.11) mm from the anterior end, respectively; eggs measured 0.120-0.139 (0.129 ± 0.001) mm long and 0.030-0.052 (0.045 ± 0.001) mm wide. It compared morphometrically with other Syphacia species described previously and showed little differences in

First case of a naturally acquired human infection with Plasmodium cynomolgi

PubMed Central

2014-01-01

Since 1960, a total of seven species of monkey malaria have been reported as transmissible to man by mosquito bite: Plasmodium cynomolgi, Plasmodium brasilianum, Plasmodium eylesi, Plasmodium knowlesi, Plasmodium inui, Plasmodium schwetzi and Plasmodium simium. With the exception of P. knowlesi, none of the other species has been found to infect humans in nature. In this report, it is described the first known case of a naturally acquired P. cynomolgi malaria in humans. The patient was a 39-year-old woman from a malaria-free area with no previous history of malaria or travel to endemic areas. Initially, malaria was diagnosed and identified as Plasmodium malariae/P. knowlesi by microscopy in the Terengganu State Health Department. Thick and thin blood films stained with 10% Giemsa were performed for microscopy examination. Molecular species identification was performed at the Institute for Medical Research (IMR, Malaysia) and in the Malaria & Emerging Parasitic Diseases Laboratory (MAPELAB, Spain) using different nested PCR methods. Microscopic re-examination in the IMR showed characteristics of Plasmodium vivax and was confirmed by a nested PCR assay developed by Snounou et al. Instead, a different PCR assay plus sequencing performed at the MAPELAB confirmed that the patient was infected with P. cynomolgi and not with P. vivax. This is the first report of human P. cynomolgi infection acquired in a natural way, but there might be more undiagnosed or misdiagnosed cases, since P. cynomolgi is morphologically indistinguishable from P. vivax, and one of the most used PCR methods for malaria infection detection may identify a P. cynomolgi infection as P. vivax. Simian Plasmodium species may routinely infect humans in Southeast Asia. New diagnostic methods are necessary to distinguish between the human and monkey malaria species. Further epidemiological studies, incriminating also the mosquito vector(s), must be performed to know the relevance of cynomolgi malaria and its

First case of a naturally acquired human infection with Plasmodium cynomolgi.

PubMed

Ta, Thuy H; Hisam, Shamilah; Lanza, Marta; Jiram, Adela I; Ismail, NorParina; Rubio, José M

2014-02-24

Since 1960, a total of seven species of monkey malaria have been reported as transmissible to man by mosquito bite: Plasmodium cynomolgi, Plasmodium brasilianum, Plasmodium eylesi, Plasmodium knowlesi, Plasmodium inui, Plasmodium schwetzi and Plasmodium simium. With the exception of P. knowlesi, none of the other species has been found to infect humans in nature. In this report, it is described the first known case of a naturally acquired P. cynomolgi malaria in humans.The patient was a 39-year-old woman from a malaria-free area with no previous history of malaria or travel to endemic areas. Initially, malaria was diagnosed and identified as Plasmodium malariae/P. knowlesi by microscopy in the Terengganu State Health Department. Thick and thin blood films stained with 10% Giemsa were performed for microscopy examination. Molecular species identification was performed at the Institute for Medical Research (IMR, Malaysia) and in the Malaria & Emerging Parasitic Diseases Laboratory (MAPELAB, Spain) using different nested PCR methods.Microscopic re-examination in the IMR showed characteristics of Plasmodium vivax and was confirmed by a nested PCR assay developed by Snounou et al. Instead, a different PCR assay plus sequencing performed at the MAPELAB confirmed that the patient was infected with P. cynomolgi and not with P. vivax.This is the first report of human P. cynomolgi infection acquired in a natural way, but there might be more undiagnosed or misdiagnosed cases, since P. cynomolgi is morphologically indistinguishable from P. vivax, and one of the most used PCR methods for malaria infection detection may identify a P. cynomolgi infection as P. vivax.Simian Plasmodium species may routinely infect humans in Southeast Asia. New diagnostic methods are necessary to distinguish between the human and monkey malaria species. Further epidemiological studies, incriminating also the mosquito vector(s), must be performed to know the relevance of cynomolgi malaria and its

Intestinal parasitic infections among expatriate workers in various occupations in Sharjah, United Arab Emirates.

PubMed

Dafalla, Abdelmunim Izzeldin Abdelrahman; Almuhairi, Shaikha Ali Salem Obaid; AlHosani, Mohamed Hassan Jasim; Mohamed, Mira Yousif; Alkous, Mariam Ibrahim Ahmed; AlAzzawi, Mousa Abdelsattar; Abakar, Adam Dawoud; Nour, Bakri Yousif Mohamed; Hasan, Hayder; AbuOdeh, Ra'ed Omar; ElBakri, Ali

2017-12-21

Intestinal parasitic infections are prevalent throughout many countries. This study aimed to determine the prevalence of intestinal parasite carriers among 21,347 expatriate workers, including food handlers and housemaids attending the public health center laboratory in Sharjah, UAE. Stool sample collection was performed throughout the period between January and December 2013. All samples were examined microscopically. Demographic data were also obtained and analyzed. Intestinal parasites were found in 3.3% (708/21,347) of the studied samples (single and multiple infections). Among positive samples, six hundred and eighty-three samples (96.5%) were positive for a single parasite: Giardia lamblia (257; 36.3%) and Entamoeba histolytica/Entamoeba dispar (220; 31.1%), respectively, whereas mono-infections with helminths accounted for 206 (29.1%) of the samples. Infection rates with single worms were: Ascaris lumbricoides (84; 11.9%), Hookworm (34; 4.8%), Trichuris trichiura (33; 4.7%), Taenia spp. (27; 3.81%), Strongyloides stercoralis (13; 1.8%), Hymenolepis nana (13; 1.8%), and Enterobius vermicularis (2; 0.28%), respectively. Infections were significantly associated with gender (x2 = 14.18; p = 0.002) with males as the most commonly infected with both groups of intestinal parasites (protozoa and helminths). A strong statistical association was noted correlating the parasite occurrence with certain nationalities (x2= 49.5, p <0.001). Furthermore, the study has also found a strong statistical correlation between parasite occurrence and occupation (x2= 15.60; p = 0.029). Multiple infections were not common (3.5% of the positive samples), although one individual (0.14%) had four helminth species, concurrently. These findings emphasized that food handlers with different pathogenic parasitic organisms may pose a significant health risk to the public.

Laboratory-acquired vaccinia virus infection in a recently immunized person--Massachusetts, 2013.

PubMed

Hsu, Christopher H; Farland, Julien; Winters, Thomas; Gunn, Julia; Caron, Donna; Evans, Jennifer; Osadebe, Lynda; Bethune, Leon; McCollum, Andrea M; Patel, Nishi; Wilkins, Kimberly; Davidson, Whitni; Petersen, Brett; Barry, M Anita

2015-05-01

On November 26, 2013, the CDC poxvirus laboratory was notified by the Boston Public Health Commission (BPHC) of an inadvertent inoculation of a recently vaccinated (ACAM2000 smallpox vaccine) laboratory worker with wild type vaccinia virus (VACV) Western Reserve. A joint investigation by CDC and BPHC confirmed orthopoxvirus infection in the worker, who had reported a needle stick in his thumb while inoculating a mouse with VACV. He experienced a non-tender, red rash on his arm, diagnosed at a local emergency department as cellulitis. He subsequently developed a necrotic lesion on his thumb, diagnosed as VACV infection. Three weeks after the injury, the thumb lesion was surgically debrided and at 2 months post-injury, the skin lesion had resolved. The investigation confirmed that the infection was the first reported VACV infection in the United States in a laboratory worker vaccinated according to the Advisory Committee on Immunization Practices (ACIP) recommendations. The incident prompted the academic institution to outline biosafety measures for working with biologic agents, such as biosafety training of laboratory personnel, vaccination (if appropriate), and steps in incident reporting. Though vaccination has been shown to be an effective measure in protecting personnel in the laboratory setting, this case report underscores the importance of proper safety measures and incident reporting.

Infections in British clinical laboratories, 1986-87.

PubMed

Grist, N R; Emslie, J A

1989-07-01

During 1986-87 this continuing survey showed 15 specific infections in the staff of 235 laboratories, representing 28,524 person years of exposure. The community was the probable source of four of the five cases of tuberculosis and one of the five cases of salmonellosis. Occupational exposure was the probable cause of four infections by Shigella flexneri, three by Salmonella typhimurium, and one by S typhi, all affecting medical laboratory scientific officers (MLSOs) in microbiology. Occupational exposure was also the probable cause of one case of tuberculosis in a mortuary technician and one of probable non-A, non-B hepatitis in a medical laboratory scientific officer haematology worker. The overall incidence of reported infections was 52.6/100,000 person years (35/100,000 for infections of probable occupational origin). The highest rates of laboratory acquired infections related to MLSO microbiology workers and mortuary technicians. No additional infections were seen as a result of extending the survey to forensic laboratories.

Childhood parasitic infections endemic to the United States.

PubMed

Barry, Meagan A; Weatherhead, Jill E; Hotez, Peter J; Woc-Colburn, Laila

2013-04-01

Endemic parasitic infections in the United States are more frequent than is commonly perceived. Intestinal parasitic infection with Cryptosporidium, Dientamoeba, and Giardia occurs most often in children in northern states during the summer months. Zoonotic Toxocara and Toxoplasma parasitic infections are more frequent in southern states, in African Americans, and in populations with lower socioeconomic status. Approximately 300, 000 people in the United States have Trypanosoma cruzi infection. Local, vector-borne transmission of T cruzi and Leishmania infections has been documented in southern states. Parasitic diseases endemic to the United States are not uncommon but are understudied. Copyright © 2013 Elsevier Inc. All rights reserved.

Effects of Age, Hemoglobin Type and Parasite Strain on IgG Recognition of Plasmodium falciparum–Infected Erythrocytes in Malian Children

PubMed Central

Zeituni, Amir E.; Miura, Kazutoyo; Diakite, Mahamadou; Doumbia, Saibou; Moretz, Samuel E.; Diouf, Ababacar; Tullo, Gregory; Lopera-Mesa, Tatiana M.; Bess, Cameron D.; Mita-Mendoza, Neida K.; Anderson, Jennifer M.; Fairhurst, Rick M.; Long, Carole A.

2013-01-01

Background Naturally-acquired antibody responses to antigens on the surface of Plasmodium falciparum-infected red blood cells (iRBCs) have been implicated in antimalarial immunity. To profile the development of this immunity, we have been studying a cohort of Malian children living in an area with intense seasonal malaria transmission. Methodology/Principal Findings We collected plasma from a sub-cohort of 176 Malian children aged 3-11 years, before (May) and after (December) the 2009 transmission season. To measure the effect of hemoglobin (Hb) type on antibody responses, we enrolled age-matched HbAA, HbAS and HbAC children. To quantify antibody recognition of iRBCs, we designed a high-throughput flow cytometry assay to rapidly test numerous plasma samples against multiple parasite strains. We evaluated antibody reactivity of each plasma sample to 3 laboratory-adapted parasite lines (FCR3, D10, PC26) and 4 short-term-cultured parasite isolates (2 Malian and 2 Cambodian). 97% of children recognized ≥1 parasite strain and the proportion of IgG responders increased significantly during the transmission season for most parasite strains. Both strain-specific and strain-transcending IgG responses were detected, and varied by age, Hb type and parasite strain. In addition, the breadth of IgG responses to parasite strains increased with age in HbAA, but not in HbAS or HbAC, children. Conclusions/Significance Our assay detects both strain-specific and strain-transcending IgG responses to iRBCs. The magnitude and breadth of these responses varied not only by age, but also by Hb type and parasite strain used. These findings indicate that studies of acquired humoral immunity should account for Hb type and test large numbers of diverse parasite strains. PMID:24124591

Clinical and laboratory characteristics of acute community-acquired urinary tract infections in adult hospitalised patients.

PubMed

Piljic, Dilista; Piljic, Dragan; Ahmetagic, Sead; Ljuca, Farid; Porobic Jahic, Humera

2010-02-01

Urinary tract infections (UTI) cause a great number of morbidity and mortality. These infections are serious complications in pregnancy, patients with diabetes, polycystic kidneys disease, sickle cell anaemia, kidney transplant and in patients with functional or structural anomalies of the urinary tract. The aim of this investigation was to determine a dominant causative agents of UTI and some of the clinical and laboratory characteristics of acute community-acquired UTI in adult hospitalised patients. We studied 200 adult patients with acute community-acquired UTI hospitalised in the Clinic for Infectious Diseases Tuzla from January 2006 to December 2007. The patients were divided into two groups: a group of patients with E. coli UTI (147) and a group of patients with non-E. coli UTI (53). In these two groups, the symptoms and signs of illness, blood test and urine analysis results were analysed. Our results have shown that the patients with E. coli UTI frequently had fever higher than 38,5 degrees C (p<0,0001), chills (p=0,0349), headache (p=0,0499), cloudy urine (p<0,0001), proteinuria (p=0,0011) and positive nitrite-test (p=0,0002). The patients with non-E. coli UTI frequently had fever lower than 38,5 degrees C (p<0,0001) and urine specific gravity <1015 (p=0,0012). There was no significant difference in blood test results between patients with E. coli and non-E. coli UTI. These clinical and laboratory findings can lead us to early etiological diagnosis of these UTI before urine culture detection of causative agents, which takes several days. Early etiological diagnosis of the E. coli and non-E. coli UTI is necessary for an urgent administration of appropriate empirical antibiotic treatment. This is very important in prevention of irreversible kidney damage, prolonged treatment, complications, as well as recidives and chronicity of the illness.

Intestinal parasitic infections among expatriate workers in various occupations in Sharjah, United Arab Emirates

PubMed Central

Dafalla, Abdelmunim Izzeldin Abdelrahman; Almuhairi, Shaikha Ali Salem Obaid; AlHosani, Mohamed Hassan Jasim; Mohamed, Mira Yousif; Alkous, Mariam Ibrahim Ahmed; AlAzzawi, Mousa Abdelsattar; Abakar, Adam Dawoud; Nour, Bakri Yousif Mohamed; Hasan, Hayder; AbuOdeh, Ra'ed Omar; ElBakri, Ali

2017-01-01

ABSTRACT Intestinal parasitic infections are prevalent throughout many countries. This study aimed to determine the prevalence of intestinal parasite carriers among 21,347 expatriate workers, including food handlers and housemaids attending the public health center laboratory in Sharjah, UAE. Stool sample collection was performed throughout the period between January and December 2013. All samples were examined microscopically. Demographic data were also obtained and analyzed. Intestinal parasites were found in 3.3% (708/21,347) of the studied samples (single and multiple infections). Among positive samples, six hundred and eighty-three samples (96.5%) were positive for a single parasite: Giardia lamblia (257; 36.3%) and Entamoeba histolytica/Entamoeba dispar (220; 31.1%), respectively, whereas mono-infections with helminths accounted for 206 (29.1%) of the samples. Infection rates with single worms were: Ascaris lumbricoides (84; 11.9%), Hookworm (34; 4.8%), Trichuris trichiura (33; 4.7%), Taenia spp. (27; 3.81%), Strongyloides stercoralis (13; 1.8%), Hymenolepis nana (13; 1.8%), and Enterobius vermicularis (2; 0.28%), respectively. Infections were significantly associated with gender (x 2 = 14.18; p = 0.002) with males as the most commonly infected with both groups of intestinal parasites (protozoa and helminths). A strong statistical association was noted correlating the parasite occurrence with certain nationalities (x 2= 49.5, p <0.001). Furthermore, the study has also found a strong statistical correlation between parasite occurrence and occupation (x 2= 15.60; p = 0.029). Multiple infections were not common (3.5% of the positive samples), although one individual (0.14%) had four helminth species, concurrently. These findings emphasized that food handlers with different pathogenic parasitic organisms may pose a significant health risk to the public. PMID:29267590

High Prevalence of Persistent Parasitic Infections in Foreign-Born, HIV-Infected Persons in the United States

PubMed Central

Hochberg, Natasha S.; Moro, Ruth N.; Sheth, Anandi N.; Montgomery, Susan P.; Steurer, Frank; McAuliffe, Isabel T.; Wang, Yun F.; Armstrong, Wendy; Rivera, Hilda N.; Lennox, Jeffrey L.; Franco-Paredes, Carlos

2011-01-01

Background Foreign-born, HIV-infected persons are at risk for sub-clinical parasitic infections acquired in their countries of origin. The long-term consequences of co-infections can be severe, yet few data exist on parasitic infection prevalence in this population. Methodology/Principal Findings This cross-sectional study evaluated 128 foreign-born persons at one HIV clinic. We performed stool studies and serologic testing for strongyloidiasis, schistosomiasis, filarial infection, and Chagas disease based on the patient's country of birth. Eosinophilia and symptoms were examined as predictors of helminthic infection. Of the 128 participants, 86 (67%) were male, and the median age was 40 years; 70 were Mexican/Latin American, 40 African, and 18 from other countries or regions. Strongyloides stercoralis antibodies were detected in 33/128 (26%) individuals. Of the 52 persons from schistosomiasis-endemic countries, 15 (29%) had antibodies to schistosome antigens; 7 (47%) had antibodies to S. haematobium, 5 (33%) to S. mansoni, and 3 (20%) to both species. Stool ova and parasite studies detected helminths in 5/85 (6%) persons. None of the patients tested had evidence of Chagas disease (n = 77) or filarial infection (n = 52). Eosinophilia >400 cells/mm3 was associated with a positive schistosome antibody test (OR 4.5, 95% CI 1.1–19.0). The only symptom significantly associated with strongyloidiasis was weight loss (OR 3.1, 95% CI 1.4–7.2). Conclusions/Significance Given the high prevalence of certain helminths and the potential lack of suggestive symptoms and signs, selected screening for strongyloidiasis and schistosomiasis or use of empiric antiparasitic therapy may be appropriate among foreign-born, HIV-infected patients. Identifying and treating helminth infections could prevent long-term complications. PMID:21532747

Hook, Line and Infection: A Guide to Culturing Parasites, Establishing Infections and Assessing Immune Responses in the Three-Spined Stickleback.

PubMed

Stewart, Alexander; Jackson, Joseph; Barber, Iain; Eizaguirre, Christophe; Paterson, Rachel; van West, Pieter; Williams, Chris; Cable, Joanne

2017-01-01

The three-spined stickleback (Gasterosteus aculeatus) is a model organism with an extremely well-characterized ecology, evolutionary history, behavioural repertoire and parasitology that is coupled with published genomic data. These small temperate zone fish therefore provide an ideal experimental system to study common diseases of coldwater fish, including those of aquacultural importance. However, detailed information on the culture of stickleback parasites, the establishment and maintenance of infections and the quantification of host responses is scattered between primary and grey literature resources, some of which is not readily accessible. Our aim is to lay out a framework of techniques based on our experience to inform new and established laboratories about culture techniques and recent advances in the field. Here, essential knowledge on the biology, capture and laboratory maintenance of sticklebacks, and their commonly studied parasites is drawn together, highlighting recent advances in our understanding of the associated immune responses. In compiling this guide on the maintenance of sticklebacks and a range of common, taxonomically diverse parasites in the laboratory, we aim to engage a broader interdisciplinary community to consider this highly tractable model when addressing pressing questions in evolution, infection and aquaculture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hepatitis E virus: do locally acquired infections in Australia necessitate laboratory testing in acute hepatitis patients with no overseas travel history?

PubMed Central

Shrestha, Ashish C.; Faddy, Helen M.; Flower, Robert L. P.; Seed, Clive R.; Keller, Anthony J.

2015-01-01

Summary Hepatitis E virus (HEV) is emerging as a global public health threat. Water-borne HEV outbreaks are common in developing countries and are associated with genotypes 1 and 2. In industrialised countries, sporadic cases of zoonotic transmission associated with genotypes 3 and 4 are increasingly being reported. Transfusion- and transplantation-transmitted HEV have been documented, although ingestion of contaminated food is thought to be the major transmission route. Severe disease is possible and chronic hepatitis infection occurs in solid-organ-transplant recipients and in patients with immunosuppressive disorders. In Australia, HEV cases are mainly travellers returning from disease endemic countries. Indeed, there are few reported cases of locally acquired HEV. Pigs in Australia have been shown to be infected with HEV, which indicates the possibility of zoonotic transmission. The extent of locally acquired infection is not known, however it may be greater than expected and may necessitate laboratory testing in patients reporting no overseas travel. PMID:25560836

Parasitic infections in sickle cell crisis: Nigerian experience.

PubMed Central

Sodipo, J. O.; Padgett, D.; Warrie, E.; Olopoenia, L.

1997-01-01

Data collected on 150 sickle cell patients in Nigeria were analyzed to determine the frequency of parasitic infections in clinical and hematologic crisis. Fifty-three adult and 97 pediatric patients (mean age: 27.6 years and 9.7 years, respectively) were studied. Of these patients, 82 were males and 68 females. One hundred thirty-nine had the SS and 11 the SC genotype. Blood samples collected from patients on admission for sickle cell-related illnesses were examined microscopically for evidence of Plasmodium sp, and stool samples were analyzed for presence of any helminth. A total of 102 parasitic infections associated with clinical cases of sickle cell crisis were recorded (malaria, 36[35.3%]; helminths, 49 ([48%]; and malaria and helminths together, 17 [16.7%]). Of the 49 helminthic infections, 26 (53.1%) were due to Ascaris lumbricoides, 15 (30.6%) were due to hookworms, 7 (14.3%) were due to Trichuris trichiura, and 1 (2%) was due to Strongyloides stercoralis. The mean hemoglobin levels during clinical crisis were 7.1 g/dL for helminths, 6.4 g/dL for malaria, and 6.1 g/dL for malaria and helminths together. Reticulocyte counts were 1.4% for helminths, 1.5% for malaria, and 1.2% for both malaria and helminths together. Severity and duration of the clinical crisis were longer for events associated with a single parasitic organism infection than for those with multiple organisms. Routine blood smear examination for malaria and stool analysis should be included in the laboratory evaluation of individuals with sickle cell anemia in developing countries as these infestations could play an important role in precipitating a crisis. PMID:9145635

Everyday and exotic foodborne parasites

PubMed Central

Lee, Marilyn B

2000-01-01

Everyday foodborne parasites, which are endemic in Canada, include the protozoans Entamoeba histolytica, Giardia lamblia and Cryptosporidium parvum. However, these parasites are most frequently acquired through unfiltered drinking water, homosexual activity or close personal contact such as in daycare centres and occasionally via a food vehicle. It is likely that many foodborne outbreaks from these protozoa go undetected. Transmission of helminth infections, such as tapeworms, is rare in Canada because of effective sewage treatment. However, a common foodborne parasite of significance is Toxoplasma gondii. Although infection can be acquired from accidental ingestion of oocysts from cat feces, infection can also result from consumption of tissue cysts in undercooked meat, such as pork or lamb. Congenital transmission poses an immense financial burden, costing Canada an estimated $240 million annually. Also of concern is toxoplasmosis in AIDS patients, which may lead to toxoplasmosis encephalitis, the second most common AIDS-related opportunistic infection of the central nervous system. Exotic parasites (ie, those acquired from abroad or from imported food) are of growing concern because more Canadians are travelling and the number of Canada's trading partners is increasing. Since 1996, over 3000 cases of Cyclospora infection reported in the United States and Canada were epidemiologically associated with importation of Guatemalan raspberries. Unlike toxoplasmosis, where strategies for control largely rest with individual practices, control of cyclosporiasis rests with government policy, which should prohibit the importation of foods at high risk. PMID:18159283

Differences in microbiological profile between community-acquired, healthcare-associated and hospital-acquired infections.

PubMed

Cardoso, Teresa; Ribeiro, Orquídea; Aragão, Irene; Costa-Pereira, Altamiro; Sarmento, António

2013-01-01

Microbiological profiles were analysed and compared for intra-abdominal, urinary, respiratory and bloodstream infections according to place of acquisition: community-acquired, with a separate analysis of healthcare-associated, and hospital-acquired. Prospective cohort study performed at a university tertiary care hospital over 1 year. Inclusion criteria were meeting the Centers for Disease Control definition of intra-abdominal, urinary, respiratory and bloodstream infections. A total of 1035 patients were included in the study. More than 25% of intra-abdominal infections were polymicrobial; multi-drug resistant gram-negatives were 38% in community-acquired, 50% in healthcare-associated and 57% in hospital-acquired. E. coli was the most prevalent among urinary infections: 69% in community-acquired, 56% in healthcare-associated and 26% in hospital-acquired; ESBL producers' pathogens were 10% in healthcare-associated and 3% in community-acquired and hospital-acquired. In respiratory infections Streptococcus pneumoniae was the most prevalent in community-acquired (54%) and MRSA in healthcare-associated (24%) and hospital-acquired (24%). A significant association was found between MRSA respiratory infection and hospitalization in the previous year (adjusted OR = 6.3), previous instrumentation (adjusted OR = 4.3) and previous antibiotic therapy (adjusted OR = 5.7); no cases were documented among patients without risk factors. Hospital mortality rate was 10% in community-acquired, 14% in healthcare-associated and 19% in hospital-acquired infection. This study shows that healthcare-associated has a different microbiologic profile than those from community or hospital acquired for the four main focus of infection. Knowledge of this fact is important because the existing guidelines for community-acquired are not entirely applicable for this group of patients.

Host age modulates parasite infectivity, virulence and reproduction.

PubMed

Izhar, Rony; Ben-Ami, Frida

2015-07-01

Host age is one of the most striking differences among hosts within most populations, but there is very little data on how age-dependent effects impact ecological and evolutionary dynamics of both the host and the parasite. Here, we examined the influence of host age (juveniles, young and old adults) at parasite exposure on host susceptibility, fecundity and survival as well as parasite transmission, using two clones of the water flea Daphnia magna and two clones of its bacterial parasite Pasteuria ramosa. Younger D. magna were more susceptible to infection than older ones, regardless of host or parasite clone. Also, younger-infected D. magna became castrated faster than older hosts, but host and parasite clone effects contributed to this trait as well. Furthermore, the early-infected D. magna produced considerably more parasite transmission stages than late-infected ones, while host age at exposure did not affect virulence as it is defined in models (host mortality). When virulence is defined more broadly as the negative effects of infection on host fitness, by integrating the parasitic effects on host fecundity and mortality, then host age at exposure seems to slide along a negative relationship between host and parasite fitness. Thus, the virulence-transmission trade-off differs strongly among age classes, which in turn affects predictions of optimal virulence. Age-dependent effects on host susceptibility, virulence and parasite transmission could pose an important challenge for experimental and theoretical studies of infectious disease dynamics and disease ecology. Our results present a call for a more explicit stage-structured theory for disease, which will incorporate age-dependent epidemiological parameters. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

Host social behavior and parasitic infection: A multifactorial approach

USGS Publications Warehouse

Ezenwa, V.O.

2004-01-01

I examined associations between several components of host social organization, including group size and gregariousness, group stability, territoriality and social class, and gastrointestinal parasite load in African bovids. At an intraspecific level, group size was positively correlated with parasite prevalence, but only when the parasite was relatively host specific and only among host species living in stable groups. Social class was also an important predictor of infection rates. Among gazelles, territorial males had higher parasite intensities than did either bachelor males or females and juveniles, suggesting that highly territorial individuals may be either more exposed or more susceptible to parasites. Associations among territoriality, grouping, and parasitism were also found across taxa. Territorial host genera were more likely to be infected with strongyle nematodes than were nonterritorial hosts, and gregarious hosts were more infected than were solitary hosts. Analyses also revealed that gregariousness and territoriality had an interactive effect on individual parasite richness, whereby hosts with both traits harbored significantly more parasite groups than did hosts with only one or neither trait. Overall, study results indicate that multiple features of host social behavior influence infection risk and suggest that synergism between traits also has important effects on host parasite load.

A syndromic approach to common parasitic diseases

PubMed Central

Shafran, Stephen D.; Chow, Anthony W.

1985-01-01

Standard textbooks discuss parasitic disease according to specific organisms. In contrast, patients with parasitic infections present to physicians with a variety of clinical manifestations that may involve any of several organ systems and that often mimic nonparasitic diseases. A syndromic approach to the clinical situation may help the physician in considering the most important parasitic agents. Many parasitic infections can be acquired in temperate climates. While often considered tropical or exotic, other parasitic diseases are now seen more frequently in developed countries because of immigration and increased world travel. In this review the clinical syndromes associated with common parasitic diseases in North America are discussed, with an emphasis on risk factors and diagnosis of specific infections. PMID:4042057

HIV and intestinal parasite co-infections among a Chinese population: an immunological profile

PubMed Central

2013-01-01

Background Parasite infections often result in a switch of the human body’s predominant immune reaction from T-helper 1 (Th1)-type to Th2-type. Hence, parasite infections are widely expected to accelerate the progression of human immunodeficiency virus (HIV) infections to acquired immunodeficiency syndrome (AIDS). In the People’s Republic of China, both parasitic diseases and AIDS are epidemic in certain rural areas, and co-infections are relatively common. However, no population-based studies have yet investigated the frequency of HIV and parasite co-infections, and its effects on immune responses. We studied (1) the immune status of an HIV-infected population, and (2) the effect of co-infection of HIV and intestinal parasites on selected parameters of the human immune system. Methods A total of 309 HIV-infected individuals were recruited and compared to an age-matched and sex-matched control group of 315 local HIV-negative individuals. Questionnaires were administered to all participants to obtain information on sociodemographic characteristics, sanitation habits, family income, and recent clinical manifestations. Two consecutive stool samples and 10 ml samples of venous blood were also collected from each individual for the diagnosis of parasite infections and quantitative measurements of selected cytokines and CD4+ T-lymphocytes, respectively. Results During the study period, 79 HIV-infected individuals were not under highly active antiretroviral therapy (HAART) and were thus included in our analysis; the prevalence of intestinal helminth infections was 6.3% and that of protozoa was 22.8%. The most common protozoan infections were Blastocystis hominis (B. hominis) (13.9%) and Cryptosporidium spp. (10.1%). The prevalence of Cryptosporidium spp. in HIV-infected individuals was significantly higher than that in HIV negative individuals (P < 0.05). Compared to the non-co-infected population, no significant difference was found for any of the measured

Comparison of intestinal parasitic infection in newly arrived and resident workers in Qatar

PubMed Central

2011-01-01

Background The rapid growth of Qatar in the last two decades has been associated with an enormous expansion of building programs in its cities and in the provision of new service industries. This in turn has attracted a large influx of immigrant workers seeking employment in jobs associated with food handling, domestic service and the building industry. Many of these immigrants come from countries in the tropics and subtropics where intestinal parasitic infections are common. Methods We analyzed intestinal parasitic infections recorded in 2008 among immigrant and long-term resident workers in Doha city, Qatar (n = 1538). Stool examinations were carried out at the Hamad Medical Corporation and at the Medical Commission in Doha using standard procedures. Results Overall, 21.5% of subjects were infected with at least one of the species recorded (8 helminth and 4 protozoan species; the highest prevalence was for hookworms = 8.3%) and there were strong regional effects on prevalence of helminths, with subjects from North East Africa and Nepal showing particularly high prevalence. Most helminths declined in prevalence in subjects that acquired residency status in Qatar, especially among female subjects, but there was a marked exception among male Nepalese workers, who continued to harbour helminth infections (notably hookworms) after they became residents. Contrary to all other regional groups the prevalence of Giardia duodenalis was higher among Nepalese residents compared with new arrivals, while Blastocystis hominis infections were more common among residents of all regions, and especially among North East Africans. Conclusions Our analysis has identified male Nepalese workers as a particular risk group continuing to harbour hookworm infection and G. duodenalis as residents, and subjects from North East Africa are as particularly likely to acquire B. hominis infection after settling in the country. These conclusions have important implications for the health

Comparison of intestinal parasitic infection in newly arrived and resident workers in Qatar.

PubMed

Abu-Madi, Marawan A; Behnke, Jerzy M; Ismail, Ahmed; Al-Olaqi, Nada; Al-Zaher, Kefah; El-Ibrahim, Roda

2011-11-04

The rapid growth of Qatar in the last two decades has been associated with an enormous expansion of building programs in its cities and in the provision of new service industries. This in turn has attracted a large influx of immigrant workers seeking employment in jobs associated with food handling, domestic service and the building industry. Many of these immigrants come from countries in the tropics and subtropics where intestinal parasitic infections are common. We analyzed intestinal parasitic infections recorded in 2008 among immigrant and long-term resident workers in Doha city, Qatar (n = 1538). Stool examinations were carried out at the Hamad Medical Corporation and at the Medical Commission in Doha using standard procedures. Overall, 21.5% of subjects were infected with at least one of the species recorded (8 helminth and 4 protozoan species; the highest prevalence was for hookworms = 8.3%) and there were strong regional effects on prevalence of helminths, with subjects from North East Africa and Nepal showing particularly high prevalence. Most helminths declined in prevalence in subjects that acquired residency status in Qatar, especially among female subjects, but there was a marked exception among male Nepalese workers, who continued to harbour helminth infections (notably hookworms) after they became residents. Contrary to all other regional groups the prevalence of Giardia duodenalis was higher among Nepalese residents compared with new arrivals, while Blastocystis hominis infections were more common among residents of all regions, and especially among North East Africans. Our analysis has identified male Nepalese workers as a particular risk group continuing to harbour hookworm infection and G. duodenalis as residents, and subjects from North East Africa are as particularly likely to acquire B. hominis infection after settling in the country. These conclusions have important implications for the health authorities in Qatar.

Natural infection of Plasmodium brasilianum in humans: Man and monkey share quartan malaria parasites in the Venezuelan Amazon.

PubMed

Lalremruata, Albert; Magris, Magda; Vivas-Martínez, Sarai; Koehler, Maike; Esen, Meral; Kempaiah, Prakasha; Jeyaraj, Sankarganesh; Perkins, Douglas Jay; Mordmüller, Benjamin; Metzger, Wolfram G

2015-09-01

The quartan malaria parasite Plasmodium malariae is the widest spread and best adapted human malaria parasite. The simian Plasmodium brasilianum causes quartan fever in New World monkeys and resembles P. malariae morphologically. Since the genetics of the two parasites are nearly identical, differing only in a range of mutations expected within a species, it has long been speculated that the two are the same. However, no naturally acquired infection with parasites termed as P. brasilianum has been found in humans until now. We investigated malaria cases from remote Yanomami indigenous communities of the Venezuelan Amazon and analyzed the genes coding for the circumsporozoite protein (CSP) and the small subunit of ribosomes (18S) by species-specific PCR and capillary based-DNA sequencing. Based on 18S rRNA gene sequencing, we identified 12 patients harboring malaria parasites which were 100% identical with P. brasilianum isolated from the monkey, Alouatta seniculus. Translated amino acid sequences of the CS protein gene showed identical immunodominant repeat units between quartan malaria parasites isolated from both humans and monkeys. This study reports, for the first time, naturally acquired infections in humans with parasites termed as P. brasilianum. We conclude that quartan malaria parasites are easily exchanged between humans and monkeys in Latin America. We hypothesize a lack of host specificity in mammalian hosts and consider quartan malaria to be a true anthropozoonosis. Since the name P. brasilianum suggests a malaria species distinct from P. malariae, we propose that P. brasilianum should have a nomenclatorial revision in case further research confirms our findings. The expansive reservoir of mammalian hosts discriminates quartan malaria from other Plasmodium spp. and requires particular research efforts.

Trichuris muris: a model of gastrointestinal parasite infection.

PubMed

Klementowicz, Joanna E; Travis, Mark A; Grencis, Richard K

2012-11-01

Infection with soil-transmitted gastrointestinal parasites, such as Trichuris trichiura, affects more than a billion people worldwide, causing significant morbidity and health problems especially in poverty-stricken developing countries. Despite extensive research, the role of the immune system in triggering parasite expulsion is incompletely understood which hinders the development of anti-parasite therapies. Trichuris muris infection in mice serves as a useful model of T. trichiura infection in humans and has proven to be an invaluable tool in increasing our understanding of the role of the immune system in promoting either susceptibility or resistance to infection. The old paradigm of a susceptibility-associated Th1 versus a resistance-associated Th2-type response has been supplemented in recent years with cell populations such as novel innate lymphoid cells, basophils, dendritic cells and regulatory T cells proposed to play an active role in responses to T. muris infection. Moreover, new immune-controlled mechanisms of expulsion, such as increased epithelial cell turnover and mucin secretion, have been described in recent years increasing the number of possible targets for anti-parasite therapies. In this review, we give a comprehensive overview of experimental work conducted on the T. muris infection model, focusing on important findings and the most recent reports on the role of the immune system in parasite expulsion.

Parasite Infection, Carcinogenesis and Human Malignancy.

PubMed

van Tong, Hoang; Brindley, Paul J; Meyer, Christian G; Velavan, Thirumalaisamy P

2017-02-01

Cancer may be induced by many environmental and physiological conditions. Infections with viruses, bacteria and parasites have been recognized for years to be associated with human carcinogenicity. Here we review current concepts of carcinogenicity and its associations with parasitic infections. The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic while the protozoan Trypanosoma cruzi, the causing agent of Chagas disease, has a dual role in the development of cancer, including both carcinogenic and anticancer properties. Although malaria per se does not appear to be causative in carcinogenesis, it is strongly associated with the occurrence of endemic Burkitt lymphoma in areas holoendemic for malaria. The initiation of Plasmodium falciparum related endemic Burkitt lymphoma requires additional transforming events induced by the Epstein-Barr virus. Observations suggest that Strongyloides stercoralis may be a relevant co-factor in HTLV-1-related T cell lymphomas. This review provides an overview of the mechanisms of parasitic infection-induced carcinogenicity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Intestinal parasitic infection among school children.

PubMed

Shakya, B; Shrestha, S; Madhikarmi, N L; Adhikari, R

2012-01-01

Intestinal parasitosis is a major public health problem of developing countries, children being major victims. Higher prevalence has been reported among school children, mostly in hilly regions of Nepal. This study aims at assessing prevalence of intestinal parasitosis among school children of a school in a border town of Nepal and the associated factors. Fecal samples from the students were examined by direct smear technique and result was correlated with their socioeconomic status and hygienic behavior. The chi-square test was used for analytical assessment. The prevalence rate was 13.9%, girls being highly infected (19.1%) than boys (10.3%) (P>0.05). Entamoeba histolytica (36.0%) was the commonest parasite followed by A. lumbricoides (28.0%). The highest positive rate was found among children of 5 years and less age (29.2%) and least among those above 12 years (5.3%) (P>0.05). Those from family size 5 and less than 5 were least infected (10.5%). Children of illiterate parents (16.7%) and farmers (17.1%) were more infected than literate ones and non-farmers (P>0.05). 8.7% of positive children had multi-parasitic infection. Children drinking untreated water (15.0%) were more infected than those drinking treated water (5.5%) (P>0.05). Intestinal parasitic infection was found among 17% school children. Awareness on infectious diseases, improving hygiene, and application of supportive programs for parents to elevate socioeconomic conditions may reduce the burden of infection.

Host-mediated impairment of parasite maturation during blood-stage Plasmodium infection

PubMed Central

Khoury, David S.; Cromer, Deborah; Akter, Jasmin; Sebina, Ismail; Elliott, Trish; Thomas, Bryce S.; Soon, Megan S. F.; James, Kylie R.; Best, Shannon E.; Haque, Ashraful; Davenport, Miles P.

2017-01-01

Severe malaria and associated high parasite burdens occur more frequently in humans lacking robust adaptive immunity to Plasmodium falciparum. Nevertheless, the host may partly control blood-stage parasite numbers while adaptive immunity is gradually established. Parasite control has typically been attributed to enhanced removal of parasites by the host, although in vivo quantification of this phenomenon remains challenging. We used a unique in vivo approach to determine the fate of a single cohort of semisynchronous, Plasmodium berghei ANKA- or Plasmodium yoelii 17XNL-parasitized red blood cells (pRBCs) after transfusion into naive or acutely infected mice. As previously shown, acutely infected mice, with ongoing splenic and systemic inflammatory responses, controlled parasite population growth more effectively than naive controls. Surprisingly, however, this was not associated with accelerated removal of pRBCs from circulation. Instead, transfused pRBCs remained in circulation longer in acutely infected mice. Flow cytometric assessment and mathematical modeling of intraerythrocytic parasite development revealed an unexpected and substantial slowing of parasite maturation in acutely infected mice, extending the life cycle from 24 h to 40 h. Importantly, impaired parasite maturation was the major contributor to control of parasite growth in acutely infected mice. Moreover, by performing the same experiments in rag1−/− mice, which lack T and B cells and mount weak inflammatory responses, we revealed that impaired parasite maturation is largely dependent upon the host response to infection. Thus, impairment of parasite maturation represents a host-mediated, immune system-dependent mechanism for limiting parasite population growth during the early stages of an acute blood-stage Plasmodium infection. PMID:28673996

The double edge to parasite escape: invasive host is less infected but more infectable.

PubMed

Keogh, Carolyn L; Miura, Osamu; Nishimura, Tomohiro; Byers, James E

2017-09-01

Nonnative species that escape their native-range parasites may benefit not only from reduced infection pathology, but also from relaxed selection on costly immune defenses, promoting reallocation of resources toward growth or reproduction. However, benefits accruing from a reduction in defense could come at the cost of increased infection susceptibility. We conducted common garden studies of the shore crab Hemigrapsus sanguineus from highly parasitized native (Japan) populations and largely parasite-free invasive (USA) populations to test for differences in susceptibility to infection by native-range rhizocephalan parasites, and to explore differences in host resource allocation. Nonnative individuals showed at least 1.8 times greater susceptibility to infection than their native counterparts, and had reduced standing metabolic rates, suggesting that less of their energy was spent on physiological self-maintenance. Our results support an indirect advantage to parasite escape via the relaxation of costly physiological defenses. However, this advantage comes at the cost of heightened susceptibility, a trade-off of parasite escape that is seldom considered. © 2017 by the Ecological Society of America.

Natural infection of Plasmodium brasilianum in humans: Man and monkey share quartan malaria parasites in the Venezuelan Amazon

PubMed Central

Lalremruata, Albert; Magris, Magda; Vivas-Martínez, Sarai; Koehler, Maike; Esen, Meral; Kempaiah, Prakasha; Jeyaraj, Sankarganesh; Perkins, Douglas Jay; Mordmüller, Benjamin; Metzger, Wolfram G.

2015-01-01

Background The quartan malaria parasite Plasmodium malariae is the widest spread and best adapted human malaria parasite. The simian Plasmodium brasilianum causes quartan fever in New World monkeys and resembles P. malariae morphologically. Since the genetics of the two parasites are nearly identical, differing only in a range of mutations expected within a species, it has long been speculated that the two are the same. However, no naturally acquired infection with parasites termed as P. brasilianum has been found in humans until now. Methods We investigated malaria cases from remote Yanomami indigenous communities of the Venezuelan Amazon and analyzed the genes coding for the circumsporozoite protein (CSP) and the small subunit of ribosomes (18S) by species-specific PCR and capillary based-DNA sequencing. Findings Based on 18S rRNA gene sequencing, we identified 12 patients harboring malaria parasites which were 100% identical with P. brasilianum isolated from the monkey, Alouatta seniculus. Translated amino acid sequences of the CS protein gene showed identical immunodominant repeat units between quartan malaria parasites isolated from both humans and monkeys. Interpretation This study reports, for the first time, naturally acquired infections in humans with parasites termed as P. brasilianum. We conclude that quartan malaria parasites are easily exchanged between humans and monkeys in Latin America. We hypothesize a lack of host specificity in mammalian hosts and consider quartan malaria to be a true anthropozoonosis. Since the name P. brasilianum suggests a malaria species distinct from P. malariae, we propose that P. brasilianum should have a nomenclatorial revision in case further research confirms our findings. The expansive reservoir of mammalian hosts discriminates quartan malaria from other Plasmodium spp. and requires particular research efforts. PMID:26501116

Parasitic infections associated with mental retardation in Egypt.

PubMed

Mohamed, N H; Salem, S A; Azab, M E; Bebars, M A; Khattab, H M; Kamal, A M; Mohamed, M S

1991-08-01

Examination of 150 mentally retarded patients for parasitic infections by urine and stool analysis revealed that 115 (76.67%) were positive. The most prevalent parasites found were T. trichiura in 56%, A. lumbricoides in 40.6% and A. duodenale in 21.33%. Double infection was present in 30.67%, triple infection in 15.33% and quadriple infection in 6%. Eosinophilia was detected in 91 (64.08%) of 142 examined cases, all were suffering from intestinal parasites. S. stercoralis was present in 11.33% by stool examination and culture and in 24 (60%) out of 40 examined cases by the IFAT. Toxocara antibodies were present in 38 (56.72%) out of 67 examined cases by the IFAT. Toxoplasma antibodies were present in 106 (74.65%) out of 142 examined cases by the IFAT.

Grouping facilitates avoidance of parasites by fish

PubMed Central

2013-01-01

Background Parasite distribution is often highly heterogeneous, and intensity of infection depends, among other things, on how well hosts can avoid areas with a high concentration of parasites. We studied the role of fish behaviour in avoiding microhabitats with a high infection risk using Oncorhynchus mykiss and cercariae of Diplostomum pseudospathaceum as a model. Spatial distribution of parasites in experimental tanks was highly heterogeneous. We hypothesized that fish in groups are better at recognizing a parasitized area and avoiding it than solitary fish. Methods Number of fish, either solitary or in groups of 5, was recorded in different compartments of a shuttle tank where fish could make a choice between areas with different risk of being infected. Intensity of infection was assessed and compared with the number of fish recorded in the compartment with parasites and level of fish motility. Results Both solitary fish and fish in groups avoided parasitized areas, but fish in groups avoided it more strongly and thus acquired significantly fewer parasites than solitary fish. Prevalence of infection among grouped and solitary fish was 66 and 92 %, respectively, with the mean abundance two times higher in the solitary fish. Between-individual variation in the number of parasites per fish was higher in the “groups” treatment (across all individuals) than in the “solitary” treatment. Avoidance behaviour was more efficient when fish were allowed to explore the experimental arena prior to parasite exposure. High motility of fish was shown to increase the acquisition of D. pseudospathaceum. Conclusion Fish in groups better avoided parasitized habitat, and acquired significantly fewer parasites than solitary fish. We suggest that fish in groups benefit from information about parasites gained from other members of a group. Grouping behaviour may be an efficient mechanism of parasite avoidance, together with individual behaviour and immune responses of fishes

Grouping facilitates avoidance of parasites by fish.

PubMed

Mikheev, Victor N; Pasternak, Anna F; Taskinen, Jouni; Valtonen, Tellervo E

2013-10-17

Parasite distribution is often highly heterogeneous, and intensity of infection depends, among other things, on how well hosts can avoid areas with a high concentration of parasites. We studied the role of fish behaviour in avoiding microhabitats with a high infection risk using Oncorhynchus mykiss and cercariae of Diplostomum pseudospathaceum as a model. Spatial distribution of parasites in experimental tanks was highly heterogeneous. We hypothesized that fish in groups are better at recognizing a parasitized area and avoiding it than solitary fish. Number of fish, either solitary or in groups of 5, was recorded in different compartments of a shuttle tank where fish could make a choice between areas with different risk of being infected. Intensity of infection was assessed and compared with the number of fish recorded in the compartment with parasites and level of fish motility. Both solitary fish and fish in groups avoided parasitized areas, but fish in groups avoided it more strongly and thus acquired significantly fewer parasites than solitary fish. Prevalence of infection among grouped and solitary fish was 66 and 92 %, respectively, with the mean abundance two times higher in the solitary fish. Between-individual variation in the number of parasites per fish was higher in the "groups" treatment (across all individuals) than in the "solitary" treatment. Avoidance behaviour was more efficient when fish were allowed to explore the experimental arena prior to parasite exposure. High motility of fish was shown to increase the acquisition of D. pseudospathaceum. Fish in groups better avoided parasitized habitat, and acquired significantly fewer parasites than solitary fish. We suggest that fish in groups benefit from information about parasites gained from other members of a group. Grouping behaviour may be an efficient mechanism of parasite avoidance, together with individual behaviour and immune responses of fishes. Avoidance of habitats with a high parasite risk

Sex steroids, immune system, and parasitic infections: facts and hypotheses.

PubMed

Nava-Castro, Karen; Hernández-Bello, Romel; Muñiz-Hernández, Saé; Camacho-Arroyo, Ignacio; Morales-Montor, Jorge

2012-07-01

It has been widely reported that the incidence and the severity of natural parasitic infections are different between males and females of several species, including humans. This sexual dimorphism involves a distinct exposure of males and females to various parasite infective stages, differential effects of sex steroids on immune cells, and direct effects of these steroids on parasites, among others. Typically, for a large number of parasitic diseases, the prevalence and intensity is higher in males than females; however, in several parasitic infections, males are more resistant than females. In the present work, we review the effects of sex hormones on immunity to protozoa and helminth parasites, which are the causal agents of several diseases in humans, and discuss the most recent research related to the role of sex steroids in the complex host-parasite relationship. © 2012 New York Academy of Sciences.

Parasites as prey in aquatic food webs: implications for predator infection and parasite transmission

USGS Publications Warehouse

Thieltges, David W.; Amundsen, Per-Arne; Hechinger, Ryan F.; Johnson, Pieter T.J.; Lafferty, Levin D.; Mouritsen, Kim N.; Preston, Daniel L.; Reise, Karsten; Zander, C. Dieter; Poulin, Robert

2013-01-01

While the recent inclusion of parasites into food-web studies has highlighted the role of parasites as consumers, there is accumulating evidence that parasites can also serve as prey for predators. Here we investigated empirical patterns of predation on parasites and their relationships with parasite transmission in eight topological food webs representing marine and freshwater ecosystems. Within each food web, we examined links in the typical predator–prey sub web as well as the predator–parasite sub web, i.e. the quadrant of the food web indicating which predators eat parasites. Most predator– parasite links represented ‘concomitant predation’ (consumption and death of a parasite along with the prey/host; 58–72%), followed by ‘trophic transmission’ (predator feeds on infected prey and becomes infected; 8–32%) and predation on free-living parasite life-cycle stages (4–30%). Parasite life-cycle stages had, on average, between 4.2 and 14.2 predators. Among the food webs, as predator richness increased, the number of links exploited by trophically transmitted parasites increased at about the same rate as did the number of links where these stages serve as prey. On the whole, our analyses suggest that predation on parasites has important consequences for both predators and parasites, and food web structure. Because our analysis is solely based on topological webs, determining the strength of these interactions is a promising avenue for future research.

Parasite burden and severity of malaria in Tanzanian children.

PubMed

Gonçalves, Bronner P; Huang, Chiung-Yu; Morrison, Robert; Holte, Sarah; Kabyemela, Edward; Prevots, D Rebecca; Fried, Michal; Duffy, Patrick E

2014-05-08

Severe Plasmodium falciparum malaria is a major cause of death in children. The contribution of the parasite burden to the pathogenesis of severe malaria has been controversial. We documented P. falciparum infection and disease in Tanzanian children followed from birth for an average of 2 years and for as long as 4 years. Of the 882 children in our study, 102 had severe malaria, but only 3 had more than two episodes. More than half of first episodes of severe malaria occurred after a second infection. Although parasite levels were higher on average when children had severe rather than mild disease, most children (67 of 102) had high-density infection (>2500 parasites per 200 white cells) with only mild symptoms before severe malaria, after severe malaria, or both. The incidence of severe malaria decreased considerably after infancy, whereas the incidence of high-density infection was similar among all age groups. Infections before and after episodes of severe malaria were associated with similar parasite densities. Nonuse of bed nets, placental malaria at the time of a woman's second or subsequent delivery, high-transmission season, and absence of the sickle cell trait increased severe-malaria risk and parasite density during infections. Resistance to severe malaria was not acquired after one or two mild infections. Although the parasite burden was higher on average during episodes of severe malaria, a high parasite burden was often insufficient to cause severe malaria even in children who later were susceptible. The diverging rates of severe disease and high-density infection after infancy, as well as the similar parasite burdens before and after severe malaria, indicate that naturally acquired resistance to severe malaria is not explained by improved control of parasite density. (Funded by the National Institute of Allergy and Infectious Diseases and others.).

Parasite and vertebrate host genetic heterogeneity determine the outcome of infection by Schistosoma mansoni.

PubMed

Nino Incani, R; Morales, G; Cesari, I M

2001-02-01

Intraspecific variation in Schistosoma mansoni infection and modulation of its expression by vertebrate host genetics was studied by evaluation of some biological parameters of the infection in BALB/c and C57BL/6 mice infected with one Brazilian (BH) and two Venezuelan (YT and SM) laboratory strains of the parasite. Mice infected with 60 cercariae of each parasite strain were euthanized at 5, 6, 8, and 12 weeks. Parameters recorded included the number of adult worms recovered by portal perfusion (infectivity); the number of eggs in the feces, the intestine, and the liver; and the ability of the eggs to cross the intestine, expressed as a quotient of the number of eggs in the intestine versus the feces. Results showed that the parasite appeared to determine the infectivity, the sex ratio, the onset and timing of oviposition, the number of eggs produced, initial egg laying toward the liver, and the ability to cross the intestinal wall. In this sense the BH strain appeared to be the most efficient and the SM strain, the most delayed; the YT strain was intermediate, although closer to the SM strain. On the other hand, the host appeared to influence the susceptibility to infection, the fecundity, and the percentage of eggs distributed in the liver and in the intestine during the chronic stage. In this sense, although they have been shown to be less susceptible to infection than BALB/c mice, C57BL/6 mice permit more eggs to be produced and exhibit similar numbers of eggs in the intestine and the liver at certain time points. It appears from these results that parasite genetics is essential for the outcome of infection with S. mansoni, but some characteristics may be quantitatively modulated by host genetics.

Fungal and Parasitic Infections of the Eye

PubMed Central

Klotz, Stephen A.; Penn, Christopher C.; Negvesky, Gerald J.; Butrus, Salim I.

2000-01-01

The unique structure of the human eye as well as exposure of the eye directly to the environment renders it vulnerable to a number of uncommon infectious diseases caused by fungi and parasites. Host defenses directed against these microorganisms, once anatomical barriers are breached, are often insufficient to prevent loss of vision. Therefore, the timely identification and treatment of the involved microorganisms are paramount. The anatomy of the eye and its surrounding structures is presented with an emphasis upon the association of the anatomy with specific infection of fungi and parasites. For example, filamentous fungal infections of the eye are usually due to penetrating trauma by objects contaminated by vegetable matter of the cornea or globe or, by extension, of infection from adjacent paranasal sinuses. Fungal endophthalmitis and chorioretinitis, on the other hand, are usually the result of antecedent fungemia seeding the ocular tissue. Candida spp. are the most common cause of endogenous endophthalmitis, although initial infection with the dimorphic fungi may lead to infection and scarring of the chorioretina. Contact lens wear is associated with keratitis caused by yeasts, filamentous fungi, and Acanthamoebae spp. Most parasitic infections of the eye, however, arise following bloodborne carriage of the microorganism to the eye or adjacent structures. PMID:11023963

Neglected Parasitic Infections in the United States: Trichomoniasis

PubMed Central

Secor, W. Evan; Meites, Elissa; Starr, Michelle C.; Workowski, Kimberly A.

2014-01-01

Trichomonas vaginalis is one of the most common human parasitic infections in the United States, as well as the most prevalent non-viral sexually transmitted infection. However, it has long received much less consideration than other parasitic and sexually transmitted diseases. Much of this inattention can be attributed to a poor understanding of the public health impact of trichomoniasis. Increasing recognition of the sequelae of infection, including increased risk of infection with human immunodeficiency virus and adverse outcomes of pregnancy, has led to increased interest in T. vaginalis. Recent innovations include development of diagnostic tests that could improve detection of the parasite. A number of important questions, such as the epidemiology among men and women, the true public health burden of symptomatic and asymptomatic T. vaginalis infections, and whether current treatments will be adequate to reduce the substantial health disparities and costs associated with trichomoniasis, need consideration to remedy neglect of this important disease. PMID:24808247

Secondary metabolites in floral nectar reduce parasite infections in bumblebees

PubMed Central

Richardson, Leif L.; Adler, Lynn S.; Leonard, Anne S.; Andicoechea, Jonathan; Regan, Karly H.; Anthony, Winston E.; Manson, Jessamyn S.; Irwin, Rebecca E.

2015-01-01

The synthesis of secondary metabolites is a hallmark of plant defence against herbivores. These compounds may be detrimental to consumers, but can also protect herbivores against parasites. Floral nectar commonly contains secondary metabolites, but little is known about the impacts of nectar chemistry on pollinators, including bees. We hypothesized that nectar secondary metabolites could reduce bee parasite infection. We inoculated individual bumblebees with Crithidia bombi, an intestinal parasite, and tested effects of eight naturally occurring nectar chemicals on parasite population growth. Secondary metabolites strongly reduced parasite load, with significant effects of alkaloids, terpenoids and iridoid glycosides ranging from 61 to 81%. Using microcolonies, we also investigated costs and benefits of consuming anabasine, the compound with the strongest effect on parasites, in infected and uninfected bees. Anabasine increased time to egg laying, and Crithidia reduced bee survival. However, anabasine consumption did not mitigate the negative effects of Crithidia, and Crithidia infection did not alter anabasine consumption. Our novel results highlight that although secondary metabolites may not rescue survival in infected bees, they may play a vital role in mediating Crithidia transmission within and between colonies by reducing Crithidia infection intensities. PMID:25694627

Co-infections determine patterns of mortality in a population exposed to parasite infection.

PubMed

Woolhouse, Mark E J; Thumbi, Samuel M; Jennings, Amy; Chase-Topping, Margo; Callaby, Rebecca; Kiara, Henry; Oosthuizen, Marinda C; Mbole-Kariuki, Mary N; Conradie, Ilana; Handel, Ian G; Poole, E Jane; Njiiri, Evalyne; Collins, Nicola E; Murray, Gemma; Tapio, Miika; Auguet, Olga Tosas; Weir, Willie; Morrison, W Ivan; Kruuk, Loeske E B; Bronsvoort, B Mark de C; Hanotte, Olivier; Coetzer, Koos; Toye, Philip G

2015-03-01

Many individual hosts are infected with multiple parasite species, and this may increase or decrease the pathogenicity of the infections. This phenomenon is termed heterologous reactivity and is potentially an important determinant of both patterns of morbidity and mortality and of the impact of disease control measures at the population level. Using infections with Theileria parva (a tick-borne protozoan, related to Plasmodium) in indigenous African cattle [where it causes East Coast fever (ECF)] as a model system, we obtain the first quantitative estimate of the effects of heterologous reactivity for any parasitic disease. In individual calves, concurrent co-infection with less pathogenic species of Theileria resulted in an 89% reduction in mortality associated with T. parva infection. Across our study population, this corresponds to a net reduction in mortality due to ECF of greater than 40%. Using a mathematical model, we demonstrate that this degree of heterologous protection provides a unifying explanation for apparently disparate epidemiological patterns: variable disease-induced mortality rates, age-mortality profiles, weak correlations between the incidence of infection and disease (known as endemic stability), and poor efficacy of interventions that reduce exposure to multiple parasite species. These findings can be generalized to many other infectious diseases, including human malaria, and illustrate how co-infections can play a key role in determining population-level patterns of morbidity and mortality due to parasite infections.

Dynamics of parasitemia of malaria parasites in a naturally and experimentally infected migratory songbird, the great reed warbler Acrocephalus arundinaceus.

PubMed

Zehtindjiev, Pavel; Ilieva, Mihaela; Westerdahl, Helena; Hansson, Bengt; Valkiūnas, Gediminas; Bensch, Staffan

2008-05-01

Little is known about the development of infection of malaria parasites of the genus Plasmodium in wild birds. We used qPCR, targeting specific mitochondrial lineages of Plasmodium ashfordi (GRW2) and Plasmodium relictum (GRW4), to monitor changes in intensities of parasitemia in captive great reed warblers Acrocephalus arundinaceus from summer to spring. The study involved both naturally infected adults and experimentally infected juveniles. The experiment demonstrated that P. ashfordi and P. relictum lineages differ substantially in several life-history traits (e.g. prepatent period and dynamics of parasitemia) and that individual hosts show substantial differences in responses to these infections. The intensity of parasitemia of lineages in mixed infections co-varied positively, suggesting a control mechanism by the host that is general across the parasite lineages. The intensity of parasitemia for individual hosts was highly repeatable suggesting variation between the host individuals in their genetic or acquired control of the infections. In future studies, care must be taken to avoid mixed infections in wild caught donors, and when possible use mosquitoes for the experiments as inoculation of infectious blood ignores important initial stages of the contact between the bird and the parasite.

Co-infections of haemosporidian and trypanosome parasites in a North American songbird.

PubMed

Soares, Letícia; Ellis, Vincenzo A; Ricklefs, Robert E

2016-12-01

Hosts frequently harbour multiple parasite infections, yet patterns of parasite co-occurrence are poorly documented in nature. In this study, we asked whether two common avian blood parasites, one haemosporidian and one trypanosome, affect each other's occurrence in individuals of a single host species. We used molecular genotyping to survey protozoan parasites in the peripheral blood of yellow-breasted chats (Aves: Passeriformes [Parulidae]: Icteria virens) from the Ozarks of Southern Missouri. We also determined whether single and co-infections differently influence white blood cell and polychromatic erythrocyte counts, the latter being a measure of regenerative anaemia. We found a positive association between the haemosporidian and trypanosome parasites, such that infection by one increases the probability that an individual host is infected by the other. Adult individuals were more likely than juveniles to exhibit haemosporidian infection, but co-infections and single trypanosome infections were not age-related. We found evidence of pathogenicity of trypanosomes in that infected individuals exhibited similar levels of regenerative anaemia as birds infected with haemosporidian parasites of the genus Plasmodium. Counts of white blood cells did not differ with respect to infection status.

Human parasitic protozoan infection to infertility: a systematic review.

PubMed

Shiadeh, Malihe Nourollahpour; Niyyati, Maryam; Fallahi, Shirzad; Rostami, Ali

2016-02-01

Protozoan parasitic diseases are endemic in many countries worldwide, especially in developing countries, where infertility is a major burden. It has been reported that such infections may cause infertility through impairment in male and female reproductive systems. We searched Medline, PubMed, and Scopus databases and Google scholar to identify the potentially relevant studies on protozoan parasitic infections and their implications in human and animal model infertility. Literature described that some of the protozoan parasites such as Trichomonas vaginalis may cause deformities of the genital tract, cervical neoplasia, and tubal and atypical pelvic inflammations in women and also non-gonoccocal urethritis, asthenozoospermia, and teratozoospermia in men. Toxopalasma gondii could cause endometritis, impaired folliculogenesis, ovarian and uterine atrophy, adrenal hypertrophy, vasculitis, and cessation of estrus cycling in female and also decrease in semen quality, concentration, and motility in male. Trypanosoma cruzi inhibits cell division in embryos and impairs normal implantation and development of placenta. Decrease in gestation rate, infection of hormone-producing glands, parasite invasion of the placenta, and overproduction of inflammatory cytokines in the oviducts and uterine horns are other possible mechanisms induced by Trypanosoma cruzi to infertility. Plasmodium spp. and Trypanosoma brucei spp. cause damage in pituitary gland, hormonal disorders, and decreased semen quality. Entamoeba histolytica infection leads to pelvic pain, salpingitis, tubo-ovarian abscess, and genital ulcers. Cutaneous and visceral leishmaniasis can induce genital lesion, testicular amyloidosis, inflammation of epididymis, prostatitis, and sperm abnormality in human and animals. In addition, some epidemiological studies have reported that rates of protozoan infections in infertile patients are higher than healthy controls. The current review indicates that protozoan parasitic

Laboratory-acquired brucellosis: a Spanish national survey.

PubMed

Bouza, E; Sánchez-Carrillo, C; Hernangómez, S; González, M José

2005-09-01

A retrospective postal survey was carried out among 1240 clinical microbiology laboratory workers in Spain. Overall, 75 (43 microbiologists and 32 technicians) had suffered from laboratory-acquired brucellosis (LAB). Considering the total number of replies (N=628), the rate of LAB was 11.9%. The risk of suffering from LAB was clearly related to the number of isolates of Brucella spp. per year. A major break in biosafety measures was recognized in 60 cases (80%). In nine cases, processing was considered to be secure, and in six cases, the source of infection was unknown. Diagnosis was based on serology in all cases. In 51 cases (68%), blood cultures confirmed diagnosis. A variety of regimens were used to treat the 75 LAB cases. The combination of tetracycline and streptomycin was the most commonly used regimen (in 35 patients), followed by the combination of tetracycline and rifampicin (in 19 cases). Only 10 patients (13.3%) suffered from complications. No differences in resolution were observed according to the antimicrobial regimen. Microbiological laboratory workers are still at risk of developing LAB. Improvements in safety seem to be the best means of

Multiple Simultaneous Gastrointestinal Parasitic Infections in a Patient with Human Immunodeficiency Virus.

PubMed

Del Pilar-Morales, Esteban A; Cardona-Rodríguez, Zaydalee; Bertrán-Pasarell, Jorge; Soto-Malave, Ruth; De León-Borras, Rafeal

2016-06-01

Patients with the human immunodeficiency virus (HIV) infection are at high risk for gastrointestinal infections causing diarrhea, particularly when those infections are parasitic in nature. This propensity is more pronounced in AIDS, where opportunistic parasitic infections may cause severe diarrhea, marked absorptive dysfunction, and significant risk of mortality. There are scant data regarding parasitic infections among HIV patients in the developed world; most studies and research come from povertystricken areas of South Africa, India, Iran, and the South Pacific. Although multiple infections with the same or different parasites have been reported, simultaneous infections are rare. We present the case of a 35-year-old man who developed a co-infection with Giardia, Cryptosporidium, and Strongyloides, simultaneously, the diagnosis being made after the judicious evaluation of a stool sample. Given the associated morbidity, prompt diagnosis and treatment are needed to avoid further complications in patients with HIV. To our knowledge this is the first reported case of triple parasitic infection in a patient with HIV.

Secondary metabolites in floral nectar reduce parasite infections in bumblebees.

PubMed

Richardson, Leif L; Adler, Lynn S; Leonard, Anne S; Andicoechea, Jonathan; Regan, Karly H; Anthony, Winston E; Manson, Jessamyn S; Irwin, Rebecca E

2015-03-22

The synthesis of secondary metabolites is a hallmark of plant defence against herbivores. These compounds may be detrimental to consumers, but can also protect herbivores against parasites. Floral nectar commonly contains secondary metabolites, but little is known about the impacts of nectar chemistry on pollinators, including bees. We hypothesized that nectar secondary metabolites could reduce bee parasite infection. We inoculated individual bumblebees with Crithidia bombi, an intestinal parasite, and tested effects of eight naturally occurring nectar chemicals on parasite population growth. Secondary metabolites strongly reduced parasite load, with significant effects of alkaloids, terpenoids and iridoid glycosides ranging from 61 to 81%. Using microcolonies, we also investigated costs and benefits of consuming anabasine, the compound with the strongest effect on parasites, in infected and uninfected bees. Anabasine increased time to egg laying, and Crithidia reduced bee survival. However, anabasine consumption did not mitigate the negative effects of Crithidia, and Crithidia infection did not alter anabasine consumption. Our novel results highlight that although secondary metabolites may not rescue survival in infected bees, they may play a vital role in mediating Crithidia transmission within and between colonies by reducing Crithidia infection intensities. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Experimental Infection and Clearance of Coccidian Parasites in Mercury-Exposed Zebra Finches.

PubMed

Ebers Smith, Jessica H; Cristol, Daniel A; Swaddle, John P

2018-01-01

Mercury is a globally distributed, persistent environmental contaminant that affects the health of many taxa. It can suppress the immune system, which often plays a role in defense against parasites. However, there have been few investigations of whether mercury affects the abilities of animals to resist parasitic infection. Here, we exposed zebra finches to a lifetime dietary exposure of methylmercury (1.2 μg/g wet weight) and experimentally infected them with coccidian parasites to examine the effect of methylmercury exposure on parasitic infection. The mercury-exposed birds did not have an altered immune response (heterophil:lymphocyte ratio) nor a reduced ability to clear the infection. However, mercury-exposed birds tended to have higher parasite loads at the time when we expected the greatest immune response (2-3 weeks post-infection). Although mercury did not greatly influence the infection-course of this parasite in captivity, responses may be more accentuated in the wild where birds face additional immune challenges.

Infection with schistosome parasites in snails leads to increased predation by prawns: implications for human schistosomiasis control.

PubMed

Swartz, Scott J; De Leo, Giulio A; Wood, Chelsea L; Sokolow, Susanne H

2015-12-01

Schistosomiasis - a parasitic disease that affects over 200 million people across the globe - is primarily transmitted between human definitive hosts and snail intermediate hosts. To reduce schistosomiasis transmission, some have advocated disrupting the schistosome life cycle through biological control of snails, achieved by boosting the abundance of snails' natural predators. But little is known about the effect of parasitic infection on predator-prey interactions, especially in the case of schistosomiasis. Here, we present the results of laboratory experiments performed on Bulinus truncatus and Biomphalaria glabrata snails to investigate: (i) rates of predation on schistosome-infected versus uninfected snails by a sympatric native river prawn, Macrobrachium vollenhovenii, and (ii) differences in snail behavior (including movement, refuge-seeking and anti-predator behavior) between infected and uninfected snails. In predation trials, prawns showed a preference for consuming snails infected with schistosome larvae. In behavioral trials, infected snails moved less quickly and less often than uninfected snails, and were less likely to avoid predation by exiting the water or hiding under substrate. Although the mechanism by which the parasite alters snail behavior remains unknown, these results provide insight into the effects of parasitic infection on predator-prey dynamics and suggest that boosting natural rates of predation on snails may be a useful strategy for reducing transmission in schistosomiasis hotspots. © 2015. Published by The Company of Biologists Ltd.

Infection with parasitic nematodes confounds vaccination efficacy

PubMed Central

Urban, Joseph F.; Steenhard, Nina R.; Solano-Aguilar, Gloria I.; Dawson, Harry D.; Iweala, Onyinye I.; Nagler, Cathryn R.; Noland, Gregory S.; Kumar, Nirbhay; Anthony, Robert M.; Shea-Donohue, Terez; Weinstock, Joel; Gause, William C.

2007-01-01

T helper (Th) cells produce signature cytokine patterns, induced largely by intracellular versus extracellular pathogens that provide the cellular and molecular basis for counter regulatory expression of protective immunity during concurrent infections. The production of IL-12 and IFN-γ, for example, resulting from exposure to many bacterial, viral, and protozoan pathogens is responsible for Th1-derived protective responses that also can inhibit development of Th2-cells expressing IL-4-dependent immunity to extracellular helminth parasites and vice versa. In a similar manner, concurrent helminth infection alters optimal vaccine-induced responses in humans and livestock; however, the consequences of this condition have not been adequately studied especially in the context of a challenge infection following vaccination. Demands for new and effective vaccines to control chronic and emerging diseases, and the need for rapid deployment of vaccines for bio security concerns requires a systematic evaluation of confounding factors that limit vaccine efficacy. One common albeit overlooked confounder is the presence of gastrointestinal nematode parasites in populations of humans and livestock targeted for vaccination. This is particularly important in areas of the world were helminth infections are prevalent, but the interplay between parasites and emerging diseases that can be transmitted worldwide make this a global issue. In addition, it is not clear if the epidemic in allergic disease in industrialized countries substitutes for geohelminth infection to interfere with effective vaccination regimens. This presentation will focus on recent vaccination studies in mice experimentally infected with Heligmosomoides polygyrus to model the condition of gastrointestinal parasite infestation in mammalian populations targeted for vaccination. In addition, a large animal vaccination and challenge model against Mycoplasma hyopneumonia in swine exposed to Ascaris suum will provide a

Risk factors for gastrointestinal parasite infections of dogs living around protected areas of the Atlantic Forest: implications for human and wildlife health.

PubMed

Curi, N H A; Paschoal, A M O; Massara, R L; Santos, H A; Guimarães, M P; Passamani, M; Chiarello, A G

2017-01-01

Despite the ubiquity of domestic dogs, their role as zoonotic reservoirs and the large number of studies concerning parasites in urban dogs, rural areas in Brazil, especially those at the wildlife-domestic animal-human interface, have received little attention from scientists and public health managers. This paper reports a cross-sectional epidemiological survey of gastrointestinal parasites of rural dogs living in farms around Atlantic Forest fragments. Through standard parasitological methods (flotation and sedimentation), 13 parasite taxa (11 helminths and two protozoans) were found in feces samples from dogs. The most prevalent were the nematode Ancylostoma (47%) followed by Toxocara (18%) and Trichuris (8%). Other less prevalent (<2%) parasites found were Capillaria, Ascaridia, Spirocerca, Taeniidae, Acantocephala, Ascaris, Dipylidium caninum, Toxascaris, and the protozoans Cystoisospora and Eimeria. Mixed infections were found in 36% of samples, mostly by Ancylostoma and Toxocara. Previous deworming had no association with infections, meaning that this preventive measure is being incorrectly performed by owners. Regarding risk factors, dogs younger than one year were more likely to be infected with Toxocara, and purebred dogs with Trichuris. The number of cats in the households was positively associated with Trichuris infection, while male dogs and low body scores were associated with mixed infections. The lack of associations with dog free-ranging behavior and access to forest or villages indicates that infections are mostly acquired around the households. The results highlight the risk of zoonotic and wildlife parasite infections from dogs and the need for monitoring and controlling parasites of domestic animals in human-wildlife interface areas.

Molecular testing for clinical diagnosis and epidemiological investigations of intestinal parasitic infections.

PubMed

Verweij, Jaco J; Stensvold, C Rune

2014-04-01

Over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. DNA samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. A variety of technologies have been applied, and some specific and general pitfalls and limitations have been identified. This review provides an overview of the multitude of methods that have been reported for the detection of intestinal parasites and offers some guidance in applying these methods in the clinical laboratory and in epidemiological studies.

First report of birds infection by intestinal parasites in Khorramabad, west Iran.

PubMed

Badparva, Ebrahim; Ezatpour, Behrouz; Azami, Mehdi; Badparva, Masoud

2015-12-01

Parasitic infections in birds are omnipresent, even when they occur in low amounts, may result in subclinical diseases. There aren't any studies, based on Iranian data, investigating the prevalence of intestinal parasitic infections in some birds' species. We conducted a cross-sectional study between December 2011 and December 2012. The fecal samples were taken from 451 birds including hen, turkey, sparrow, pigeon and decorative birds. The samples screened for intestinal parasitic infections using direct smear, formalin-ether concentration technique, modified Ziehl-Neelsen staining, Culture in RPMI 1640 medium, sporulation with potassium dichromate and Trichrome and Giemsa staining. Out of 451 birds' species, 157 (34.8 %), were infected with one or more type of intestinal parasites. We identified two nematode, two cestoda species and five protozoan parasites species. No trematodes were found in the samples studied. The parasites identified among birds involved Raillietina spp. (4.2 %) and Eimeria spp. (7.1 %) were the most common helminthes and protozoa respectively. From total of birds study, 12 (2.7 %) and 6 (1.3 %) have two and three mixed infections respectively. Intestinal parasitic infections are common in birds in west Iran. The future studies are needed in order to determine to which extent the infections influence mortality and performance of the birds.

Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae): Aspects of the ecology of parasite-vector interactions

PubMed Central

Murat, Paula Guerra; de Medeiros, Márcio José; Souza, Alda Izabel; de Oliveira, Alessandra Gutierrez

2017-01-01

Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis–infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis–infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial capacity for L

Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae): Aspects of the ecology of parasite-vector interactions.

PubMed

Falcão de Oliveira, Everton; Oshiro, Elisa Teruya; Fernandes, Wagner de Souza; Murat, Paula Guerra; Medeiros, Márcio José de; Souza, Alda Izabel; Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi

2017-02-01

Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial capacity for L. infantum

Cryptosporidiosis and other intestinal parasitic infections in patients with chronic diarrhea.

PubMed

Mahdi, Nadham K; Ali, Naeel H

2004-09-01

To consider the relationship of the parasitic infections including cryptosporidium with chronic diarrhea. Also the effect of chronic disease as pulmonary tuberculosis (TB) and nosocomial infection on the occurrence rate of parasites in cases of chronic diarrhea. Stool samples were collected from 205 patients in teaching, general, child and maternity hospitals in Basrah, Iraq, suffering from chronic diarrhea during 2000. Out of these patients, there were 40 patients with pulmonary TB and 50 inpatients with nosocomial infection. Also 175 apparently healthy individuals who have no episodes of diarrhea for at least 2-months were served as a control group. Direct smear method and then formalin ether sedimentation method were carried out for stool samples to detect intestinal parasites. Fecal smears were prepared from the sediment and stained by the modified Ziehl Neelsen stain for the recovery of red pink oocysts of cryptosporidium. Out of the 205 examined patients, cryptosporidium oocysts were found to be excreted in 20 (9.7%) patients in comparing to 1.1% of the control group. The difference is statistically significant. There were 109 (53.2%) patients found to be positive for intestinal parasitic infections compared to 26 (14.8%) of the control group. The difference is also statistically significant. Out of the 40 TB patients, 2 (5%) were found to excrete cryptosporidium oocysts and also 27 (67.3%) were positive for intestinal parasites. In addition, there were 4 (8%) excreting cryptosporidium oocysts and 23 (46%) infecting by intestinal parasites among the in patients with nosocomial infection. Both acid and non-acid fast parasites should be considered in the differential diagnosis of undiagnosed chronic diarrhea especially among patients with pulmonary TB or nosocomial infection.

Filtering out parasites: sand crabs (Lepidopa benedicti) are infected by more parasites than sympatric mole crabs (Emerita benedicti)

PubMed Central

2017-01-01

Two digging decapod crustaceans, the sand crab species Lepidopa benedicti and the mole crab species Emerita benedicti, both live in the swash zone of fine sand beaches. They were examined for two parasites that infect decapod crustaceans in the region, an unidentified nematode previously shown to infect L. benedicti, and cestode tapeworm larvae, Polypocephalus sp., previously shown to infect shrimp (Litopenaeus setiferus). Lepidopa benedicti were almost always infected with both parasite species, while E. benedicti were rarely infected with either parasite species. This difference in infection pattern suggests that tapeworms are ingested during sediment feeding in L. benedicti, which E. benedicti avoid by filter feeding. Larger L. benedicti had more Polypocephalus sp. larvae. The thoracic ganglia, which make up the largest proportion of neural tissue, contained the largest numbers of Polypocephalus sp. larvae. Intensity of Polypocephalus sp. infection was not correlated with how long L. benedicti remained above sand in behavioural tests, suggesting that Polypocephalus sp. do not manipulate the sand crabs in a way that facilitates trophic transmission of the parasite. Litopenaeus setiferus may be a primary host for Polypocephalus sp., and L. benedict may be a secondary, auxiliary host. PMID:28951818

Alphabetical Index of Parasitic Diseases

MedlinePlus

... Z Index Laboratory Diagnostic Assistance Parasitic Disease and Malaria Strategic Priorities: 2015—2020 About our Division Get ... Lymphatic filariasis (Filariasis, Elephantiasis) Back To Top M Malaria ( Plasmodium Infection) Microsporidiosis ( Microsporidia Infection ) Mite Infestation (Scabies) ...

Induction of dendritic cell migration upon Toxoplasma gondii infection potentiates parasite dissemination.

PubMed

Lambert, Henrik; Hitziger, Niclas; Dellacasa, Isabel; Svensson, Mattias; Barragan, Antonio

2006-10-01

The processes leading to systemic dissemination of the obligate intracellular parasite Toxoplasma gondii remain unelucidated. In vitro studies on human and murine dendritic cells (DC) revealed that active invasion of DC by Toxoplasma induces a state of hypermotility in DC, enabling transmigration of infected DC across endothelial cell monolayers in the absence of chemotactic stimuli. Infected DC exhibited upregulation of maturation markers and co-stimulatory molecules. While modulation of cell adhesion molecules CD11/CD18 was similar for Toxoplasma-infected DC and lipopolysaccharide (LPS)-matured DC, Toxoplasma-infected DC did not exhibit upregulation of CD54/ICAM-1. Induction of host cell migration in vitro required live intracellular parasite(s) and was inhibited by uncoupling the Gi-protein signalling pathway with pertussis toxin, but did not depend on CCR5, CCR7 or Toll/interleukin-1 receptor signalling. When migration of Toxoplasma-infected DC was compared with migration of LPS-stimulated DC in vivo, similar or higher numbers of Toxoplasma-infected DC reached the mesenteric lymph nodes and spleen respectively. Adoptive transfer of Toxoplasma-infected DC resulted in more rapid dissemination of parasites to distant organs and in exacerbation of infection compared with inoculation with free parasites. Altogether, these findings show that Toxoplasma is able to subvert the regulation of host cell motility and likely exploits the host's natural pathways of cellular migration for parasite dissemination.

Molecular Testing for Clinical Diagnosis and Epidemiological Investigations of Intestinal Parasitic Infections

PubMed Central

Stensvold, C. Rune

2014-01-01

SUMMARY Over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. DNA samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. A variety of technologies have been applied, and some specific and general pitfalls and limitations have been identified. This review provides an overview of the multitude of methods that have been reported for the detection of intestinal parasites and offers some guidance in applying these methods in the clinical laboratory and in epidemiological studies. PMID:24696439

Parasitism and the evolutionary ecology of animal personality

PubMed Central

Barber, Iain; Dingemanse, Niels J.

2010-01-01

The ecological factors responsible for the evolution of individual differences in animal personality (consistent individual differences in the same behaviour across time and contexts) are currently the subject of intense debate. A limited number of ecological factors have been investigated to date, with most attention focusing on the roles of resource competition and predation. We suggest here that parasitism may play a potentially important, but largely overlooked, role in the evolution of animal personalities. We identify two major routes by which parasites might influence the evolution of animal personality. First, because the risk of acquiring parasites can be influenced by an individual's behavioural type, local parasite regimes may impose selection on personality traits and behavioural syndromes (correlations between personality traits). Second, because parasite infections have consequences for aspects of host ‘state’, parasites might induce the evolution of individual differences in certain types of host behaviour in populations with endemic infections. Also, because infection often leads to specific changes in axes of personality, parasite infections have the potential to decouple behavioural syndromes. Host–parasite systems therefore provide researchers with valuable tools to study personality variation and behavioural syndromes from a proximate and ultimate perspective. PMID:21078659

Ecology of malaria parasites infecting Southeast Asian macaques: evidence from cytochrome b sequences

PubMed Central

Putaporntip, Chaturong; Jongwutiwes, Somchai; Thongaree, Siriporn; Seethamchai, Sunee; Grynberg, Priscila; Hughes, Austin L.

2010-01-01

Although malaria parasites infecting non-human primates are important models for human malaria, little is known of the ecology of infection by these parasites in the wild. We extensively sequenced cytochrome b (cytb) of malaria parasites (Apicomplexa: Haemosporida) from free-living Southeast Asian monkeys Macaca nemestrina and M. fascicularis. The two most commonly observed taxa were P. inui and Hepatocystis sp., but certain other sequences did not cluster closely with any previously sequenced species. Most of the major clades of parasites were found in both Macaca species; and the two most commonly occurring parasite infected the two Macaca species at approximately equal levels. However, P. inui showed evidence of genetic differentiation between the populations infecting the two Macaca species, suggesting limited movement of this parasite among hosts. Moreover, coinfection with Plasmodium and Hepatocystis species occurred significantly less frequently than expected on the basis of the rates of infection with either taxon alone, suggesting the possibility of competitive exclusion. The results revealed unexpectedly complex communities of Plasmodium and Hepatocystis taxa infecting wild Southeast Asian monkeys. Parasite taxa differed with respect to both the frequency of between-host movement and their frequency of coinfection. PMID:20646216

Fish hepatic glutathione-S-transferase activity is affected by the cestode parasites Schistocephalus solidus and Ligula intestinalis: evidence from field and laboratory studies.

PubMed

Frank, Sabrina Nadine; Faust, Steffen; Kalbe, Martin; Trubiroha, Achim; Kloas, Werner; Sures, Bernd

2011-06-01

The activity of hepatic glutathione-S-transferase (GST) was analysed in 3 different fish species with respect to fish sex and infection with parasites. In both sexes of laboratory bred three-spined sticklebacks (Gasterosteus aculeatus) experimentally infected with Schistocephalus solidus (Cestoda), a significantly lower GST-activity was found for infected fish compared to control. After field sampling of roach (Rutilus rutilus) from Lake Müggelsee (MS) and the Reservoir Listertalsperre (LTS), the GST-activity showed significantly lower values for males infected with Ligula intestinalis from MS (25%) and for infected females from LTS (55%). L. intestinalis-infected female chub (Leuciscus cephalus) from LTS also appeared to have a lower GST-activity. Thus, it could be shown that the presence of parasites significantly affects GST-activity in different fish species resulting in a decreased GST-activity due to infection. Our results therefore emphasize the need for more integrative approaches in environmental pollution research to clearly identify the possible effects of parasites in an effort to develop biomarkers for evaluating environmental health.

Parasitic infections associated with malignancy and leprosy.

PubMed

Azab, M E; Mohamed, N H; Salem, S A; Safar, E H; Bebars, M A; Sabry, N M; Mohamed, M S

1992-04-01

Results of parasitic infections, as revealed by urine and stool examination was significant (P less than 0.05) in 43.3% of patients suffering from different malignant diseases and non significant (P greater than 0.05) in 29.3% of leprosy patients compared to 22% in control subjects. The most prevalent parasites were E. histolytica and G. lamblia. Cryptosporidium occysts were not detected. By stool examination and culture, S. stercoralis larvae were detected only in the malignancy group. The most common parasites occurring concomitantly were A. duodenale and S. stercoralis. By the IFAT, strongyloidiasis gave significantly higher positive results in the malignancy group than in the leprosy and control groups. IFAT for toxocariasis, showed highly significant positivity in the leprosy group and significantly positivity in the malignancy group. For toxoplasmosis, it showed highly significant positive results in both leprosy and malignancy groups. Eosinophilia was significantly more prominent among malignancy patients and insignificant among those with leprosy. Parasitic infection detected by urine and stool examination among patients with eosinophilia was found in 76% of the malignancy patients and in 66.7% of the leprosy patients.

Pathological and Ecological Host Consequences of Infection by an Introduced Fish Parasite

PubMed Central

Britton, J. Robert; Pegg, Josephine; Williams, Chris F.

2011-01-01

The infection consequences of the introduced cestode fish parasite Bothriocephalus acheilognathi were studied in a cohort of wild, young-of-the-year common carp Cyprinus carpio that lacked co-evolution with the parasite. Within the cohort, parasite prevalence was 42% and parasite burdens were up to 12% body weight. Pathological changes within the intestinal tract of parasitized carp included distension of the gut wall, epithelial compression and degeneration, pressure necrosis and varied inflammatory changes. These were most pronounced in regions containing the largest proportion of mature proglottids. Although the body lengths of parasitized and non-parasitized fish were not significantly different, parasitized fish were of lower body condition and reduced weight compared to non-parasitized conspecifics. Stable isotope analysis (δ15N and δ13C) revealed trophic impacts associated with infection, particularly for δ15N where values for parasitized fish were significantly reduced as their parasite burden increased. In a controlled aquarium environment where the fish were fed ad libitum on an identical food source, there was no significant difference in values of δ15N and δ13C between parasitized and non-parasitized fish. The growth consequences remained, however, with parasitized fish growing significantly slower than non-parasitized fish, with their feeding rate (items s−1) also significantly lower. Thus, infection by an introduced parasite had multiple pathological, ecological and trophic impacts on a host with no experience of the parasite. PMID:22022606

Intestinal Parasite Co-infection among Pulmonary Tuberculosis Cases without Human Immunodeficiency Virus Infection in a Rural County in China

PubMed Central

Li, Xin-Xu; Chen, Jia-Xu; Wang, Li-Xia; Tian, Li-Guang; Zhang, Yu-Ping; Dong, Shuang-Pin; Hu, Xue-Guang; Liu, Jian; Wang, Feng-Feng; Wang, Yue; Yin, Xiao-Mei; He, Li-Jun; Yan, Qiu-Ye; Zhang, Hong-Wei; Xu, Bian-Li; Zhou, Xiao-Nong

2014-01-01

Epidemiologic studies of co-infection with tuberculosis (TB) and intestinal parasites in humans have not been extensively investigated in China. A cross-section study was conducted in a rural county of Henan Province, China. Pulmonary TB (PTB) case-patients receiving treatment for infection with Mycobacterium tuberculosis and healthy controls matched for geographic area, age, and sex were surveyed by using questionnaires. Fecal and blood specimens were collected for detection of intestinal parasites, routine blood examination, and infection with human immunodeficiency virus. The chi-square test was used for univariate analysis and multivariate logistic regression models were used to adjust for potential confounding factors. A total of 369 persons with PTB and 366 healthy controls were included; all participants were negative for human immunodeficiency virus. The overall prevalence of intestinal parasites in persons with PTB was 14.9%, including intestinal protozoa (7.9%) and helminthes (7.6%). The infection spectrum of intestinal parasites was Entamoeba spp. (1.4%), Blastocystis hominis (6.2%), Trichomonas hominis (0.3%), Clonorchis sinensis (0.3%), Ascaris lumbricoides (0.5%), Trichuris trichiura (2.2%), and hookworm (4.6%). The prevalence of intestinal parasites showed no significant difference between persons with PTB and healthy controls after adjusting for potential confounding factors. There was no factor that affected infection rates for intestinal parasites between the two groups. Infection with intestinal parasites of persons with PTB was associated with female sex (adjusted odds ratio [AOR] = 2.05, 95% confidence interval [CI] = 1.01–4.17), body mass index ≤ 19 (AOR = 3.02, 95% CI = 1.47–6.20), and anemia (AOR = 2.43, 95% CI = 1.17–5.03). Infection of healthy controls was only associated with an annual labor time in farmlands > 2 months (AOR = 4.50, 95% CI = 2.03–10.00). In addition, there was no significant trend between rates of infection with

Effect of parasitic infection on dopamine biosynthesis in dopaminergic cells

PubMed Central

Martin, H.L.; Alsaady, I.; Howell, G.; Prandovszky, E.; Peers, C.; Robinson, P.; McConkey, G.A.

2015-01-01

Infection by the neurotropic agent Toxoplasma gondii alters rodent behavior and can result in neuropsychiatric symptoms in humans. Little is understood regarding the effects of infection on host neural processes but alterations to dopaminergic neurotransmission are implicated. We have previously reported elevated levels of dopamine (DA) in infected dopaminergic cells however the involvement of the host enzymes and fate of the produced DA were not defined. In order to clarify the effects of infection on host DA biosynthetic enzymes and DA packaging we examined enzyme levels and activity and DA accumulation and release in T. gondii-infected neurosecretory cells. Although the levels of the host tyrosine hydroxylase (TH) and DOPA decarboxylase and AADC (DDC) did not change significantly in infected cultures, DDC was found within the parasitophorous vacuole (PV), the vacuolar compartment where the parasites reside, as well as in the host cytosol in infected dopaminergic cells. Strikingly, DDC was found within the intracellular parasite cysts in infected brain tissue. This finding could provide some explanation for observations of DA within tissue cysts in infected brain as a parasite-encoded enzyme with TH activity was also localized within tissue cysts. In contrast, cellular DA packaging appeared unchanged in single-cell microamperometry experiments and only a fraction of the increased DA was accessible to high potassium-induced release. This study provides some understanding of how this parasite produces elevated DA within dopaminergic cells without the toxic ramifications of free cytosolic DA. The mechanism for synthesis and packaging of DA by T. gondii-infected dopaminergic cells may have important implications for the effects of chronic T. gondii infection on humans and animals. PMID:26297895

Risk factors associated with intestinal parasitic infections among inmates of Kisii prison, Kisii county, Kenya.

PubMed

Rop, Dickson Cheruiyot; Nyanchongi, Benson Omweri; Nyangeri, Johnson; Orucho, Vincent Obino

2016-08-02

Intestinal parasitic infections are a major health problem worldwide. In Kenya intestinal parasitic infections are highly prevalent especially in prisons due to poor and/or inadequate infrastructure. The aim of this study was to establish the risk factors associated with intestinal parasites infection among inmates of Kisii prison, Kisii county, Kenya. Fresh stool samples of 384 inmates in Kisii prison aged 20 years and above, were screened for intestinal parasitic infections between February and August 2015. Stool samples were processed using direct fecal smear and formol-ether sedimentation techniques for confirmation then they were examined microscopically. Multiple logistic regression analysis was used to establish the relationship of various factors and practices with the occurrence of intestinal parasites. The differences were considered statistically significant at P < 0.05. Of the 384 inmates screened, 95 (24.7 %) were infected with one or more intestinal parasites. Of the positive inmates, 58 (15.1 %) were infected with one species of protozoa while 24 (5.2 %) were infected with at least one species of helminthes and 13 (3.5 %) had mixed infections of species of intestinal parasites. Washing of hands before meals and after visiting toilets significantly reduced risk of infections (P < 0.05). The level of education was inversely related to the risk of intestinal parasites infection where by inmates at post primary education were least infected with intestinal parasites infection as compared to unschooled inmates (P < 0.05). Wearing of shoes was seen to significantly reduce parasitic infections (P ≤ 0.05). Duties assigned to inmates did not significantly determine the risk of intestinal parasitic infection (P > 0.05). Male inmates had significantly more intestinal parasites infections 57 (21.8 %) compared to females 28 (8.1 %) (P < 0.05). Inmates within ages 20-29 years were more infected (11.3 %) compared to the age group of >60�

First reported outbreak of locally acquired hepatitis E virus infection in Australia.

PubMed

Yapa, Chaturangi M; Furlong, Catriona; Rosewell, Alexander; Ward, Kate A; Adamson, Sheena; Shadbolt, Craig; Kok, Jen; Tracy, Samantha L; Bowden, Scott; Smedley, Elizabeth J; Ferson, Mark J; Sheppeard, Vicky; McAnulty, Jeremy M

2016-04-18

To determine the source and extent of a locally acquired hepatitis E virus (HEV) infection outbreak. A cluster of notified cases of HEV infection linked to a single restaurant (X) was identified in May 2014. People with laboratory-confirmed HEV infection in New South Wales between January 2013 and December 2014 were interviewed about potential risk factors for HEV infection. Co-diners at restaurant X and patients with suspected but unexplained viral hepatitis were retrospectively tested. Foods eaten by the infected persons were compared with those of seronegative co-diners. HEV RNA detected in sera from infected persons was sequenced and genotyped. Implicated foods were traced back to their sources. Potential sources of infection, including overseas travel and foods eaten, and origin of implicated food products. In 55 serologically confirmed cases of HEV infection, 24 people had not travelled overseas during their incubation periods. Of the 24, 17 reported having eaten at restaurant X, 15 of whom could be interviewed. All reported consuming pork liver pâté, compared with only four of seven uninfected co-diners (P < 0.05). The other seven people with locally acquired infections each reported consuming a pork product during their incubation periods. HEV RNA was detected in 16 of the 24 cases; all were of genotype 3. Sequencing indicated greater than 99% homology among restaurant X isolates. HEV RNA was isolated from pork sausages from a batch implicated in one of the locally acquired infections not linked with restaurant X. The pork livers used for pâté preparation by restaurant X were traced to a single Australian farm. This is the first reported HEV outbreak in Australia. HEV should be considered in patients presenting with a compatible illness, even without a history of overseas travel. Pork products should be thoroughly cooked before consumption.

Physiological Correlates of Multiple Parasitic Infections in Side-Blotched Lizards.

PubMed

Spence, Austin R; Durso, Andrew M; Smith, Geoffrey D; Skinner, Heather M; French, Susannah S

We investigated the presence of ectoparasites and hemoparasites in side-blotched lizards (Uta stansburiana) across a large part of their range and measured how parasitic infection related to several key physiological indicators of health. Blood samples were collected from 132 lizards from central Arizona, southern Utah, and eastern Oregon. Hemoparasites were found in 22 individuals (3.2% prevalence in Arizona, 19.1% in Utah, and 6.3% in Oregon), and ectoparasites were found on 51 individuals (56.3% prevalence in Arizona, 56.1% in Utah, and 6.7% in Oregon), with 11 individuals infected with both. Hemoparasites and ectoparasites were found in all three states. Immunocompetence was higher in individuals infected with both hemoparasites and ectoparasites. Body condition, glucocorticoid levels, and reproductive investment were not related to infection status. Our study provides evidence that parasitic infection is associated with an active immune system in wild reptiles but may not impose other costs usually associated with parasites.

Fiddler crabs (Uca spp.) as model hosts for laboratory infections of Hematodinium perezi.

PubMed

O'Leary, Patricia A; Shields, Jeffrey D

2017-02-01

The parasitic dinoflagellate, Hematodinium perezi, negatively impacts the commercially important blue crab, Callinectes sapidus. The parasite is a host generalist, but it has not been reported from littoral fiddler crabs living within a few meters of habitat known to harbor infected blue crabs. In the first study, populations of three species of fiddler crab were screened for natural infections. The infection status of field-collected and lab-inoculated crabs was determined by screening fresh hemolymph with a 0.3% neutral red solution. Fiddler crabs were collected by hand in an area adjacent to where infected blue crabs were commonly collected. None of the 431 fiddlers had natural infections. In two separate studies, three species of fiddler crabs, Uca minax, U. pugnax, and U. pugilator, were evaluated for their susceptibility to H. perezi via inoculation of trophic stages. Uca minax inoculated with 10,000 cells of H. perezi were monitored for progression of the parasite. During hemolymph screenings of disease progression, filamentous trophonts, ameboid trophonts, and clump colonies were observed, indicative of active infections. In the second study, the minimum infective dose in U. minax was investigated. Fiddler crabs were inoculated with 0, 100, 1000, or 10,000 cells per crab. The minimum dose was determined to be approximately 1000 ameboid trophonts per crab. All three species of fiddler crab were susceptible to H. perezi via inoculation. The parasite was serially transferred from fiddler crabs to blue crabs without loss of infectivity. Survival studies indicated similar progression patterns to those observed in blue crabs. Based on our results fiddler crabs can serve as a laboratory model for investigating H. perezi infections and may be useful for comparative studies with blue crabs. Copyright © 2016 Elsevier Inc. All rights reserved.

Opportunistic and other intestinal parasitic infections in AIDS patients, HIV seropositive healthy carriers and HIV seronegative individuals in southwest Ethiopia.

PubMed

Mariam, Zelalem T; Abebe, Gemeda; Mulu, Andargachew

2008-12-01

Human Immunodeficiency Virus (HIV) infection leads to acquired immunodeficiency syndrome (AIDS) and major causes of morbidity and mortality of such patients are opportunistic infections caused by viral, bacterial, fungal and parasitic pathogens. To determine the magnitude of opportunistic and non-opportunistic intestinal parasitic infections among AIDS patients and HIV positive carrier individuals. Cross-sectional study was conducted among AIDS patients, HIV positive healthy carriers and HIV negative individuals in Jimma University Hospital, Mother Theresa Missionary Charity Centre, Medan Acts Projects and Mekdim HIV positive persons and AIDS orphans' national association from January to May, 2004. Convenient sampling technique was employed to identify the study subjects and hence a total of 160 subjects were included. A pre-tested structured questionnaire was used to collect socio-demographic data of the patients. Stool samples were examined by direct saline, iodine wet mount, formol-ether sedimentation concentration, oocyst concentration and modified Ziehl-Neelsen staining technique. Out of 160 persons enrolled in this study 100 (62.5%) (i.e. 65 male and 35 female) were infected with one or more intestinal parasites. The highest rate 36 (69.2%) of intestinal parasites were observed among HIV/AIDS patients, followed by HIV positive healthy carriers 35 (61.4%) of and HIV negative individuals (29 (56.9%). Isospora belli 2 (3.9%), Cryptosporidum parvum 8 (15.4%), Strongyloides stercoralis 6 (11.5%) and Blastocystis 2 (3.9%) were found only in HIV/AIDS groups I. belli, C. parvum, S. stercoralis and Blastocystis are the major opportunistic intestinal parasites observed in HIV/AIDS patients. Therefore, early detection and treatment of these parasites are important to improve the quality of life of HIV/AIDS patients with diarrhoea.

Eotaxin-1 is involved in parasite clearance during chronic filarial infection.

PubMed

Gentil, K; Lentz, C S; Rai, R; Muhsin, M; Kamath, A D; Mutluer, O; Specht, S; Hübner, M P; Hoerauf, A

2014-02-01

Eosinophil migration as key feature of helminth infection is increased during infection with filarial nematodes. In a mouse model of filariasis, we investigated the role of the eosinophil-attracting chemokine Eotaxin-1 on disease outcome. BALB/c and Eotaxin-1(-/-) mice were infected with the rodent filaria Litomosoides sigmodontis, and parasitic parameters, cellular migration to the site of infection, and cellular responsiveness were investigated. We found increased parasite survival but unaffected eosinophil migration to the site of infection in Eotaxin-1(-/-) mice. Expression of CD80 and CD86 was reduced on eosinophils from Eotaxin-1(-/-) mice after in vitro TLR2 stimulation and exposure to filarial antigen, respectively, suggesting a potential reduced activation state of eosinophils in Eotaxin-1 deficient mice. We further demonstrated that macrophages from Eotaxin-1(-/-) mice produce decreased amounts of IL-6 in vitro, a cytokine found to be associated with parasite containment, suggesting possible mechanisms by which Eotaxin-1 regulates activation of inflammatory cells and thus parasite survival. © 2013 John Wiley & Sons Ltd.

Prevalence of intestinal parasitic infections in military personnel and military dogs, Thailand.

PubMed

Leelayoova, Saovanee; Siripattanapipong, Suradej; Naaglor, Tawee; Taamasri, Paanjit; Mungthin, Mathirut

2009-02-01

To determine the prevalence of intestinal parasitic infections and risk factors among military personnel and military dogs at the Military Dog Center, Veterinary and Remount Department, Royal Thai Army, Thailand. A cross-sectional study was conducted in January 2006 to examine intestinal parasitic infections using wet preparation and, formalin-ethyl acetate concentration. Modified acid fast and gram-chromotrope stains were used to identify Cryptosporidium spp. and microsporidia, respectively. Culture for Blastocystis was performed using Jone's medium. Genotypic characterization of Blastocystis and Giardia duodenalis were also determined using PCR-RFLP. To determine the risk factors and outcomes of intestinal parasitic infections, standardized questionnaires were used in the present study. Of 317 military personnel, the prevalence of intestinal parasitic infections was 22.4%. Blastocystis was the most predominant intestinal protozoa infection of 14.5% while G. duodenalis was only 1.3%. The prevalence of other helminthic infections were 4.8% which were Strongyloides stercoralis (2.5%), Hookworm (1.0%), Opisthorchis viverrini (1.0%), and Taenia spp. (0.3%), respectively. Blastocystis subtype 1 was identified in 25 positive culture specimens while all 4 positive of G. duodenalis were analyzed as Assemblage B, subgenotype IV. The presented data could not indicate that intestinal parasitic infections and blastocystosis in this army population were significantly linked to risk association among groups with regard to rank, age group, working unit, area of residence, animal contact, source and treatment of drinking water. Of 189 military dogs, the prevalence of intestinal parasitic infections was only 3.7% which was Blastocystis sp. (2.6%), S. stercoralis (0.5%), and Entamoeba coli (0.5%), respectively. The predominant intestinal parasites found in this population, such as Blastocystis sp. and G duodenalis transmit to humans via fecal-oral route so that improvement of

A cross-sectional study on intestinal parasitic infections in rural communities, northeast Thailand.

PubMed

Boonjaraspinyo, Sirintip; Boonmars, Thidarut; Kaewsamut, Butsara; Ekobol, Nuttapon; Laummaunwai, Porntip; Aukkanimart, Ratchadawan; Wonkchalee, Nadchanan; Juasook, Amornrat; Sriraj, Pranee

2013-12-01

Despite the existence of effective anthelmintics, parasitic infections remain a major public health problem in Southeast Asia, including Thailand. In rural communities, continuing infection is often reinforced by dietary habits that have a strong cultural basis and by poor personal hygiene and sanitation. This study presents a survey of the prevalence of intestinal parasitic infections among the people in rural Thailand. The community-based cross-sectional study was conducted in villages in Khon Kaen Province, northeastern Thailand, from March to August 2013. A total of 253 stool samples from 102 males and 140 females, aged 2-80 years, were prepared using formalin-ethyl acetate concentration methods and examined using light microscopy. Ninety-four individuals (37.2%) were infected with 1 or more parasite species. Presence of parasitic infection was significantly correlated with gender (P=0.001); nearly half of males in this survey (49.0%) were infected. Older people had a higher prevalence than younger members of the population. The most common parasite found was Opisthorchis viverrini (26.9%), followed by Strongyloides stercoralis (9.5%), Taenia spp. (1.6%), echinostomes (0.4%), and hookworms (0.4%). The prevalence of intestinal protozoa was Blastocystis hominis 1.6%, Entamoeba histolytica 0.8%, Entamoeba coli 0.8%, Balantidium coli 0.4%, Iodamoeba bütschlii 0.4%, and Sarcocystis hominis 0.4%. Co-infections of various helminths and protozoa were present in 15.9% of the people. The present results show that the prevalence of parasitic infections in this region is still high. Proactive education about dietary habits, personal hygiene, and sanitation should be provided to the people in this community to reduce the prevalence of intestinal parasite infections. Moreover, development of policies and programs to control parasites is needed.

A Cross-Sectional Study on Intestinal Parasitic Infections in Rural Communities, Northeast Thailand

PubMed Central

Boonjaraspinyo, Sirintip; Kaewsamut, Butsara; Ekobol, Nuttapon; Laummaunwai, Porntip; Aukkanimart, Ratchadawan; Wonkchalee, Nadchanan; Juasook, Amornrat; Sriraj, Pranee

2013-01-01

Despite the existence of effective anthelmintics, parasitic infections remain a major public health problem in Southeast Asia, including Thailand. In rural communities, continuing infection is often reinforced by dietary habits that have a strong cultural basis and by poor personal hygiene and sanitation. This study presents a survey of the prevalence of intestinal parasitic infections among the people in rural Thailand. The community-based cross-sectional study was conducted in villages in Khon Kaen Province, northeastern Thailand, from March to August 2013. A total of 253 stool samples from 102 males and 140 females, aged 2-80 years, were prepared using formalin-ethyl acetate concentration methods and examined using light microscopy. Ninety-four individuals (37.2%) were infected with 1 or more parasite species. Presence of parasitic infection was significantly correlated with gender (P=0.001); nearly half of males in this survey (49.0%) were infected. Older people had a higher prevalence than younger members of the population. The most common parasite found was Opisthorchis viverrini (26.9%), followed by Strongyloides stercoralis (9.5%), Taenia spp. (1.6%), echinostomes (0.4%), and hookworms (0.4%). The prevalence of intestinal protozoa was Blastocystis hominis 1.6%, Entamoeba histolytica 0.8%, Entamoeba coli 0.8%, Balantidium coli 0.4%, Iodamoeba bütschlii 0.4%, and Sarcocystis hominis 0.4%. Co-infections of various helminths and protozoa were present in 15.9% of the people. The present results show that the prevalence of parasitic infections in this region is still high. Proactive education about dietary habits, personal hygiene, and sanitation should be provided to the people in this community to reduce the prevalence of intestinal parasite infections. Moreover, development of policies and programs to control parasites is needed. PMID:24516280

Patients' Hand Washing and Reducing Hospital-Acquired Infection.

PubMed

Haverstick, Stacy; Goodrich, Cara; Freeman, Regi; James, Shandra; Kullar, Rajkiran; Ahrens, Melissa

2017-06-01

Hand hygiene is important to prevent hospital-acquired infections. Patients' hand hygiene is just as important as hospital workers' hand hygiene. Hospital-acquired infection rates remain a concern across health centers. To improve patients' hand hygiene through the promotion and use of hand washing with soap and water, hand sanitizer, or both and improve patients' education to reduce hospital-acquired infections. In August 2013, patients in a cardiothoracic postsurgical step-down unit were provided with individual bottles of hand sanitizer. Nurses and nursing technicians provided hand hygiene education to each patient. Patients completed a 6-question survey before the intervention, at hospital discharge and 1, 2, and 3 months after the intervention. Hospital-acquired infection data were tracked monthly by infection prevention staff. Significant correlations were found between hand hygiene and rates of infection with vancomycin-resistant enterococci ( P = .003) and methicillin-resistant Staphylococcus aureus ( P = .01) after the intervention. After the implementation of hand hygiene interventions, rates of both infections declined significantly and patients reported more staff offering opportunities for and encouraging hand hygiene. This quality improvement project demonstrates that increased hand hygiene compliance by patients can influence infection rates in an adult cardiothoracic step-down unit. The decreased infection rates and increased compliance with hand hygiene among the patients may be attributed to the implementation of patient education and the increased accessibility and use of hand sanitizer. ©2017 American Association of Critical-Care Nurses.

Inter- and intraspecific conflicts between parasites over host manipulation

PubMed Central

Hafer, Nina; Milinski, Manfred

2016-01-01

Host manipulation is a common strategy by which parasites alter the behaviour of their host to enhance their own fitness. In nature, hosts are usually infected by multiple parasites. This can result in a conflict over host manipulation. Studies of such a conflict in experimentally infected hosts are rare. The cestode Schistocephalus solidus (S) and the nematode Camallanus lacustris (C) use copepods as their first intermediate host. They need to grow for some time inside this host before they are infective and ready to be trophically transmitted to their subsequent fish host. Accordingly, not yet infective parasites manipulate to suppress predation. Infective ones manipulate to enhance predation. We experimentally infected laboratory-bred copepods in a manner that resulted in copepods harbouring (i) an infective C plus a not yet infective C or S, or (ii) an infective S plus a not yet infective C. An infective C completely sabotaged host manipulation by any not yet infective parasite. An infective S partially reduced host manipulation by a not yet infective C. We hence show experimentally that a parasite can reduce or even sabotage host manipulation exerted by a parasite from a different species. PMID:26842574

Can Mixed Parasite Infections Thwart Targeted Malaria Elimination Program in India?

PubMed

Singh, Upasana Shyamsunder; Siwal, Nisha; Pande, Veena; Das, Aparup

2017-01-01

India is highly endemic to malaria with prevalence of all five species of human malaria parasites of Plasmodium genus. India is set for malaria elimination by 2030. Since cases of mixed Plasmodium species infections remain usually undetected but cause huge disease burden, in order to understand the distributional prevalence of both monospecies infections and mixed species infections in India, we collated published data on the differential infection incidences of the five different malaria parasites based on PCR diagnostic assay. About 11% of total cases were due to mixed species infection. Among several interesting observations on both single and mixed parasitic infections, incidences of Plasmodium falciparum monoinfection were found to be significantly higher than P. vivax monoinfection. Also, P. malariae seems to be emerging as a potential malaria threat in India. Putting all the facts together, it appears that the dream of achieving malaria elimination in India will not be completely successful without dealing with mixed species infection.

Impairment of T Cell Function in Parasitic Infections

PubMed Central

Rodrigues, Vasco; Cordeiro-da-Silva, Anabela; Laforge, Mireille; Ouaissi, Ali; Akharid, Khadija; Silvestre, Ricardo; Estaquier, Jérôme

2014-01-01

In mammals subverted as hosts by protozoan parasites, the latter and/or the agonists they release are detected and processed by sensors displayed by many distinct immune cell lineages, in a tissue(s)-dependent context. Focusing on the T lymphocyte lineage, we review our present understanding on its transient or durable functional impairment over the course of the developmental program of the intracellular parasites Leishmania spp., Plasmodium spp., Toxoplasma gondii, and Trypanosoma cruzi in their mammalian hosts. Strategies employed by protozoa to down-regulate T lymphocyte function may act at the initial moment of naïve T cell priming, rendering T cells anergic or unresponsive throughout infection, or later, exhausting T cells due to antigen persistence. Furthermore, by exploiting host feedback mechanisms aimed at maintaining immune homeostasis, parasites can enhance T cell apoptosis. We will discuss how infections with prominent intracellular protozoan parasites lead to a general down-regulation of T cell function through T cell anergy and exhaustion, accompanied by apoptosis, and ultimately allowing pathogen persistence. PMID:24551250

Nutritional status, intestinal parasite infection and allergy among school children in northwest Ethiopia.

PubMed

Amare, Bemnet; Ali, Jemal; Moges, Beyene; Yismaw, Gizachew; Belyhun, Yeshambel; Gebretsadik, Simon; Woldeyohannes, Desalegn; Tafess, Ketema; Abate, Ebba; Endris, Mengistu; Tegabu, Desalegn; Mulu, Andargachew; Ota, Fusao; Fantahun, Bereket; Kassu, Afework

2013-01-12

Parasitic infections have been shown to have deleterious effects on host nutritional status. In addition, although helmintic infection can modulate the host inflammatory response directed against the parasite, a causal association between helminths and allergy remains uncertain. The present study was therefore designed to evaluate the relationship between nutritional status, parasite infection and prevalence of allergy among school children. A cross sectional study was performed involving school children in two elementary schools in Gondar, Ethiopia. Nutritional status of these children was determined using anthropometric parameters (weight-for-age, height-for-age and BMI-for-age). Epi-Info software was used to calculate z-scores. Stool samples were examined using standard parasitological procedures. The serum IgE levels were quantified by total IgE ELISA kit following the manufacturer's instruction. A total of 405 children (with mean age of 12.09.1 ± 2.54 years) completed a self-administered allergy questionnaire and provided stool samples for analysis. Overall prevalence of underweight, stunting and thinness/wasting was 15.1%, 25.2%, 8.9%, respectively. Of the total, 22.7% were found to be positive for intestinal parasites. The most prevalent intestinal parasite detected was Ascaris lumbricoides (31/405, 7.6%). There was no statistically significant association between prevalence of malnutrition and the prevalence of parasitic infections. Median total serum IgE level was 344 IU/ml (IQR 117-2076, n=80) and 610 IU/ml (143-1833, n=20), respectively, in children without and with intestinal parasite infection (Z=-0.198, P>0.8). The prevalence of self reported allergy among the subset was 8%. IgE concentration was not associated either with the presence of parasitic infection or history of allergy. The prevalence of malnutrition, intestinal parasitism and allergy was not negligible in this population. In addition, there was no significant association between the

Intestinal parasitic infections among prison inmates and tobacco farm workers in Shewa Robit, north-central Ethiopia.

PubMed

Mamo, Hassen

2014-01-01

Intestinal parasitic infections (IPIs) particularly soil-transmitted helminthiasis (STH) and schistosomiasis are among neglected tropical diseases (NTDs) globally. Apart from being associated with anemia, malabsorption and retarded cognitive development these diseases are complicating the clinical picture of more serious infections like HIV, TB and malaria. Renewed and up-to-date information on the epidemiology of IPIs in more vulnerable groups such as irrigated-farm workers and prisoners would significantly contribute towards improving the health condition of such at-risk groups. A cross-sectional survey was conducted to determine the prevalence of IPIs among prison inmates and tobacco farm workers in Shewa-Robit, north-central Ethiopia in November 2008. A total of 236 fecal samples were examined microscopically to detect helminths and/or protozoa using direct-smear and formol-ether concentration methods. Overall, 8 intestinal parasite species have been recovered singly or in combinations from 146 (61.8 %) samples. The prevalence in prison population (88/121 = 72.7%) was significantly higher than that in tobacco farm (58/115 = 50.4%). There were no significant differences in the prevalence of IPI by most socio-demographics. Except for hookworm there was no significant difference in parasite prevalence between different age-groups though the frequency of individual parasites slightly varied between the age-groups. Multivariate logistic regression analysis showed that inmates were more likely to acquire IPIs than tobacco-farm workers (Odds Ratio (OR) = 2.62, 95% confidence interval (CI) = 1.52-4.5). In addition, participants who did not report past treatment for IPIs were more likely to acquire IPIs than participants who self-reported treatment for IPIs in the past twelve months (OR = 3.25, 95% CI = 1.75-6.06). All other socio-demographics were not significantly associated with IPIs in univariate analysis. Entamoeba histolytica/dispar/moshkovskii was the most

Intestinal Parasitic Infections among Prison Inmates and Tobacco Farm Workers in Shewa Robit, North-Central Ethiopia

PubMed Central

Mamo, Hassen

2014-01-01

Background Intestinal parasitic infections (IPIs) particularly soil-transmitted helminthiasis (STH) and schistosomiasis are among neglected tropical diseases (NTDs) globally. Apart from being associated with anemia, malabsorption and retarded cognitive development these diseases are complicating the clinical picture of more serious infections like HIV, TB and malaria. Renewed and up-to-date information on the epidemiology of IPIs in more vulnerable groups such as irrigated-farm workers and prisoners would significantly contribute towards improving the health condition of such at-risk groups. Methods A cross-sectional survey was conducted to determine the prevalence of IPIs among prison inmates and tobacco farm workers in Shewa-Robit, north-central Ethiopia in November 2008. A total of 236 fecal samples were examined microscopically to detect helminths and/or protozoa using direct-smear and formol-ether concentration methods. Results Overall, 8 intestinal parasite species have been recovered singly or in combinations from 146 (61.8 %) samples. The prevalence in prison population (88/121 = 72.7%) was significantly higher than that in tobacco farm (58/115 = 50.4%). There were no significant differences in the prevalence of IPI by most socio-demographics. Except for hookworm there was no significant difference in parasite prevalence between different age-groups though the frequency of individual parasites slightly varied between the age-groups. Multivariate logistic regression analysis showed that inmates were more likely to acquire IPIs than tobacco-farm workers (Odds Ratio (OR)  = 2.62, 95% confidence interval (CI)  = 1.52–4.5). In addition, participants who did not report past treatment for IPIs were more likely to acquire IPIs than participants who self-reported treatment for IPIs in the past twelve months (OR = 3.25, 95% CI = 1.75–6.06). All other socio-demographics were not significantly associated with IPIs in univariate analysis

Parasites and phytoplankton, with special emphasis on dinoflagellate infections.

PubMed

Park, Myung Gil; Yih, Wonho; Coats, D Wayne

2004-01-01

Planktonic members of most algal groups are known to harbor intracellular symbionts, including viruses, bacteria, fungi, and protozoa. Among the dinoflagellates, viral and bacterial associations were recognized a quarter century ago, yet their impact on host populations remains largely unresolved. By contrast, fungal and protozoan infections of dinoflagellates are well documented and generally viewed as playing major roles in host population dynamics. Our understanding of fungal parasites is largely based on studies for freshwater diatoms and dinoflagellates, although fungal infections are known for some marine phytoplankton. In freshwater systems, fungal chytrids have been linked to mass mortalities of host organisms, suppression or retardation of phytoplankton blooms, and selective effects on species composition leading to successional changes in plankton communities. Parasitic dinoflagellates of the genus Amoebophrya and the newly described Perkinsozoa, Parvilucifera infectans, are widely distributed in coastal waters of the world where they commonly infect photosynthetic and heterotrophic dinoflagellates. Recent work indicates that these parasites can have significant impacts on host physiology, behavior, and bloom dynamics. Thus, parasitism needs to be carefully considered in developing concepts about plankton dynamics and the flow of material in marine food webs.

Unique physiology of host-parasite interactions in microsporidia infections.

PubMed

Williams, Bryony A P

2009-11-01

Microsporidia are intracellular parasites of all major animal lineages and have a described diversity of over 1200 species and an actual diversity that is estimated to be much higher. They are important pathogens of mammals, and are now one of the most common infections among immunocompromised humans. Although related to fungi, microsporidia are atypical in genomic biology, cell structure and infection mechanism. Host cell infection involves the rapid expulsion of a polar tube from a dormant spore to pierce the host cell membrane and allow the direct transfer of the spore contents into the host cell cytoplasm. This intimate relationship between parasite and host is unique. It allows the microsporidia to be highly exploitative of the host cell environment and cause such diverse effects as the induction of hypertrophied cells to harbour prolific spore development, host sex ratio distortion and host cell organelle and microtubule reorganization. Genome sequencing has revealed that microsporidia have achieved this high level of parasite sophistication with radically reduced proteomes and with many typical eukaryotic pathways pared-down to what appear to be minimal functional units. These traits make microsporidia intriguing model systems for understanding the extremes of reductive parasite evolution and host cell manipulation.

Information and Guidelines for Identification of Children with Parasitic Intestinal Infections.

ERIC Educational Resources Information Center

Doi, Lorraine

This report presents (1) information on the incidence, causes, development, transmission, control and prevention of parasitic infections and (2) a report of how Hawaiian Follow Through Students infected by parasites were identified and provided with treatment. The students were enrolled in kindgergarten through third grade classes at three…

Water-seeking behavior in worm-infected crickets and reversibility of parasitic manipulation

PubMed Central

Ponton, Fleur; Lefèvre, Thierry; Guerin, Patrick M.; Lebarbenchon, Camille; Duneau, David; Biron, David G.; Thomas, Frédéric

2011-01-01

One of the most fascinating examples of parasite-induced host manipulation is that of hairworms, first, because they induce a spectacular “suicide” water-seeking behavior in their terrestrial insect hosts and, second, because the emergence of the parasite is not lethal per se for the host that can live several months following parasite release. The mechanisms hairworms use to increase the encounter rate between their host and water remain, however, poorly understood. Considering the selective landscape in which nematomorph manipulation has evolved as well as previously obtained proteomics data, we predicted that crickets harboring mature hairworms would display a modified behavioral response to light. Since following parasite emergence in water, the cricket host and parasitic worm do not interact physiologically anymore, we also predicted that the host would recover from the modified behaviors. We examined the effect of hairworm infection on different behavioral responses of the host when stimulated by light to record responses from uninfected, infected, and ex-infected crickets. We showed that hairworm infection fundamentally modifies cricket behavior by inducing directed responses to light, a condition from which they mostly recover once the parasite is released. This study supports the idea that host manipulation by parasites is subtle, complex, and multidimensional. PMID:22476265

Changes to cholesterol trafficking in macrophages by Leishmania parasites infection.

PubMed

Semini, Geo; Paape, Daniel; Paterou, Athina; Schroeder, Juliane; Barrios-Llerena, Martin; Aebischer, Toni

2017-08-01

Leishmania spp. are protozoan parasites that are transmitted by sandfly vectors during blood sucking to vertebrate hosts and cause a spectrum of diseases called leishmaniases. It has been demonstrated that host cholesterol plays an important role during Leishmania infection. Nevertheless, little is known about the intracellular distribution of this lipid early after internalization of the parasite. Here, pulse-chase experiments with radiolabeled cholesteryl esterified to fatty acids bound to low-density lipoproteins indicated that retention of this source of cholesterol is increased in parasite-containing subcellular fractions, while uptake is unaffected. This is correlated with a reduction or absence of detectable NPC1 (Niemann-Pick disease, type C1), a protein responsible for cholesterol efflux from endocytic compartments, in the Leishmania mexicana habitat and infected cells. Filipin staining revealed a halo around parasites within parasitophorous vacuoles (PV) likely representing free cholesterol accumulation. Labeling of host cell membranous cholesterol by fluorescent cholesterol species before infection revealed that this pool is also trafficked to the PV but becomes incorporated into the parasites' membranes and seems not to contribute to the halo detected by filipin. This cholesterol sequestration happened early after infection and was functionally significant as it correlated with the upregulation of mRNA-encoding proteins required for cholesterol biosynthesis. Thus, sequestration of cholesterol by Leishmania amastigotes early after infection provides a basis to understand perturbation of cholesterol-dependent processes in macrophages that were shown previously by others to be necessary for their proper function in innate and adaptive immune responses. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Heterogeneities in Leishmania infantum Infection: Using Skin Parasite Burdens to Identify Highly Infectious Dogs

PubMed Central

Calvo-Bado, Leo; Garcez, Lourdes M.; Quinnell, Rupert J.

2014-01-01

Background The relationships between heterogeneities in host infection and infectiousness (transmission to arthropod vectors) can provide important insights for disease management. Here, we quantify heterogeneities in Leishmania infantum parasite numbers in reservoir and non-reservoir host populations, and relate this to their infectiousness during natural infection. Tissue parasite number was evaluated as a potential surrogate marker of host transmission potential. Methods Parasite numbers were measured by qPCR in bone marrow and ear skin biopsies of 82 dogs and 34 crab-eating foxes collected during a longitudinal study in Amazon Brazil, for which previous data was available on infectiousness (by xenodiagnosis) and severity of infection. Results Parasite numbers were highly aggregated both between samples and between individuals. In dogs, total parasite abundance and relative numbers in ear skin compared to bone marrow increased with the duration and severity of infection. Infectiousness to the sandfly vector was associated with high parasite numbers; parasite number in skin was the best predictor of being infectious. Crab-eating foxes, which typically present asymptomatic infection and are non-infectious, had parasite numbers comparable to those of non-infectious dogs. Conclusions Skin parasite number provides an indirect marker of infectiousness, and could allow targeted control particularly of highly infectious dogs. PMID:24416460

Assessment of nurses' performance related to control of some parasites acquired from fresh vegetables as a patient safety measure in a military hospital.

PubMed

Ahmed Saleh, Ahmed Megahed; El-Raouf Ali, Hisham Abd; Mohamed Ahmed, Salwa Abdalla; Mohamed, Naglaa Elsaid; Morsy, Tosson A

2014-12-01

Foodborne parasitic infection in the hospital constitutes a major health problem particularly for patients who are more vulnerable than healthy subjects to parasitic risks. Parasitic infection. represents an area of concern for advanced practice nurse. The work assessed the military nursing staff performance regarding the nosocomial food-borne parasitic infection control. Research design; A descriptive research design was used to identify knowledge, attitudes and practice of nurses related to nosocomial food-borne parasitic infection control measures. The study was conducted at a general military hospital. 50 nurses, the whole available number who covered the inclusion, criteria. DATA COLLECTION TOOLS: It included; (1): Structured interview sheet was constructed after reviewing the relevant literature to elicit information, it included two parts a) subjects' sociodemographic characteristics b) nurses' knowledge regarding nosocomial parasites infections. (2): RATING SCALE: to assess attitude of nursing staff towards nosocomial parasites infections and its prevention. (3): Obselrvational CHECKLIST: to assess the nurses' practice of self-protection and' control of nosocomial parasitic' infections control measures.. A statistically insignificant difference between knowledge levels about nosocomial parasites infection among military nurses. More than half of participant nurses had positive attitude towards nosoconijal parasite infection control and prevention without significant difference between all topics (P>0.056). That most participant nurses had unsatisfactory practice to infection control measures with significant lower score for procurement, storage and preparation of raw material followed by personal hygiene (P<0.05). Nurses in all roles and settings can demonstrate leadership in infection prevention. and control by using their knowledge, skill and judgment to initiate appropriate and immediate infection control procedures.

Prevalence of opportunistic intestinal parasitic infection among HIV infected patients who are taking antiretroviral treatment at Jimma Health Center, Jimma, Ethiopia.

PubMed

Zeynudin, A; Hemalatha, K; Kannan, S

2013-02-01

One of the major health problems among HIV sero-positive patients are superimposed infections due to the deficient immunity. Furthermore, intestinal parasitic (IP) infections, which are also one of the basic health problems in tropical regions, are common in these patients. Infection by opportunistic pathogens, including various forms of intestinal parasites has been the hall mark of HIV since the beginning of the epidemic. To study the prevalence of opportunistic intestinal parasitic infection among HIV patients who are taking antiretroviral treatment (ART) in Jimma, Ethiopia. Patient samples were diagnosed by examination of single stool specimen which was examined as fresh wet mounts, formal-ether concentration technique and modified Ziehl-Neelsen staining technique. Data was obtained from 91 study subjects selected by convenience sampling method. The overall prevalence of intestinal parasitic infections was found to be 39.56%. Eight types of intestinal parasites was identified, the most dominant being, Ascaris lumbricoides, 21.67%, Entamoeba histolytica, 15% and Cryptosporidium parvum 13.33%. The prevalence of opportunistic parasite was 15.38%, the prevalence of non-opportunistic parasite was 20.87% and the prevalence of both opportunistic and non opportunistic was 3.29%. The study indicated that intestinal parasites were still a problem in the study area. Data also showed that among the predisposing factors, habit of hand washing before meal, usage of latrine and duration after treatment was statistically associated with intestinal parasitic infections.

Global issues in allergy and immunology: Parasitic infections and allergy.

PubMed

Cruz, Alvaro A; Cooper, Philip J; Figueiredo, Camila A; Alcantara-Neves, Neuza M; Rodrigues, Laura C; Barreto, Mauricio L

2017-11-01

Allergic diseases are on the increase globally in parallel with a decrease in parasitic infection. The inverse association between parasitic infections and allergy at an ecological level suggests a causal association. Studies in human subjects have generated a large knowledge base on the complexity of the interrelationship between parasitic infection and allergy. There is evidence for causal links, but the data from animal models are the most compelling: despite the strong type 2 immune responses they induce, helminth infections can suppress allergy through regulatory pathways. Conversely, many helminths can cause allergic-type inflammation, including symptoms of "classical" allergic disease. From an evolutionary perspective, subjects with an effective immune response against helminths can be more susceptible to allergy. This narrative review aims to inform readers of the most relevant up-to-date evidence on the relationship between parasites and allergy. Experiments in animal models have demonstrated the potential benefits of helminth infection or administration of helminth-derived molecules on chronic inflammatory diseases, but thus far, clinical trials in human subjects have not demonstrated unequivocal clinical benefits. Nevertheless, there is sufficiently strong evidence to support continued investigation of the potential benefits of helminth-derived therapies for the prevention or treatment of allergic and other inflammatory diseases. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Status of intestinal parasitic infections among residents of Jimma Town, Ethiopia.

PubMed

Jejaw, Ayalew; Zeynudin, Ahmed; Zemene, Endalew; Belay, Tariku

2014-08-07

Intestinal parasites cause considerable morbidity and mortality in the world, especially in developing countries like Ethiopia. Both urban and rural inhabitants are vulnerable to infection with intestinal parasites in developing countries. The aim of this study was to determine the status of intestinal parasitic infections (IPIs) among residents of Jimma Town, seven years after high prevalence was reported. Four hundred and thirty four residents of Jimma Town were included in this study. By the cross-sectional survey, the overall prevalence of intestinal parasites was 209 (48.2%). Nine species of intestinal parasites were isolated, Ascaris lumbricoides and Trichuris trichiura being the most predominant. Residence in Hermata Mentina kebele, Adjusted Odds Ratio (AOR), 3.0, 95% CI, 1.71-5.39), age less than 10 years (AOR, 3.7, 95% CI, 1.33-10.36), illiteracy (AOR, 3.2, 95% CI, 1.64-6.19), estimated monthly family income of less than 500 Ethiopian Birr (AOR, 2.9, 95% CI, 1.32-4.90) and irregular washing hands before meal (AOR, 5.3, 95% CI, 1.36-21.07) were predictors of IPI in this study. The retrospective study revealed a significant decrease (P = 0.037) in the proportion of patients infected with intestinal parasites out of those who requested stool examination over the six-year period. This study confirms that IPIs are still common among residents of Jimma Town. Nearly half of the study participants were infected with at least one intestinal parasite. Public health interventions targeting prevention of IPIs should be strengthened in Jimma Town.

Vertebrate Cell Cycle Modulates Infection by Protozoan Parasites

NASA Astrophysics Data System (ADS)

Dvorak, James A.; Crane, Mark St. J.

1981-11-01

Synchronized HeLa cell populations were exposed to Trypanosoma cruzi or Toxoplasma gondii, obligate intracellular protozoan parasites that cause Chagas' disease and toxoplasmosis, respectively, in humans. The ability of the two parasites to infect HeLa cells increased as the HeLa cells proceeded from the G1 phase to the S phase of their growth cycle and decreased as the cells entered G2-M. Characterization of the S-phase cell surface components responsible for this phenomenon could be beneficial in the development of vaccines against these parasitic diseases.

Fish immune responses to parasitic copepod (namely sea lice) infection.

PubMed

Fast, Mark D

2014-04-01

Parasitic copepods, in particular sea lice, have considerable impacts upon global freshwater and marine fisheries, with major economic consequences recognized primarily in aquaculture. Sea lice have been a contentious issue with regards to interactions between farmed and wild populations of fish, in particular salmonids, and their potential for detrimental effects at a population level. The following discussion will pertain to aquatic parasitic copepod species for which we have significant information on the host-parasite interaction and host response to infection (Orders Cyclopoida, Poecilostomatoida and Siphonostomatoida). This review evaluates prior research in terms of contributions to understanding parasite stage specific responses by the host, and in many cases draws upon model organisms like Lepeophtheirus salmonis and Atlantic salmon to convey important concepts in fish responses to parasitic copepod infection. The article discusses TH1 and TH2-like host responses in light of parasite immunomodulation of the host, current methods of immunological stimulation and where the current and future work in this field is heading. Copyright © 2013 Elsevier Ltd. All rights reserved.

Prevalence of parasitic infections in HIV-positive patients in southern Ethiopia: a cross-sectional study.

PubMed

Fekadu, Sintayehu; Taye, Kefyalew; Teshome, Wondu; Asnake, Solomon

2013-11-15

Intestinal parasitic infections are a major public health burden in tropical countries. Although all HIV/AIDS patients are susceptible to parasitic infections, those having lower immune status are at greater risk. The aim of this study was to determine the prevalence of intestinal parasitic infections in patients living with HIV/AIDS. This was a facility-based cross-sectional study. A total of 343 consecutively sampled HIV/AIDS patients from the HIV care clinic of Hawassa University Referral Hospital were included. Subjects were interviewed for demographic variables and diarrheal symptoms using structured questionnaires. Stool examinations and CD4 cells counts were also performed. The prevalence of intestinal parasitic infection was 47.8% among HIV/AIDS patients; single helminthic infection prevalence (22.7%) was higher than that the prevalence of protozoal infections (14.6%). About 54% of study participants had chronic diarrhea while 3.4% had acute diarrhea. The prevalence of intestinal parasites in patients with chronic diarrhea was significantly higher than in acute diarrhea (p <0.05). Non-opportunistic intestinal parasite infections such as Ascaris lumbricoides, Taenia spp., and hookworm were commonly found, regardless of immune status or diarrheal symptoms. Opportunistic and non-opportunistic intestinal parasitic infection were more frequent in patients with a CD4 count of <200/mm(3) (OR=9.5; 95% CI: 4.64-19.47) when compared with patients with CD4 counts of ≥500 cells/mm(3). Intestinal parasitic infections should be suspected in HIV/AIDS-infected patients with advanced disease presenting with chronic diarrhea. Patients with low CD4 counts should be examined critically for intestinal parasites, regardless of diarrheal status.

Nutritional status, intestinal parasite infection and allergy among school children in Northwest Ethiopia

PubMed Central

2013-01-01

Background Parasitic infections have been shown to have deleterious effects on host nutritional status. In addition, although helmintic infection can modulate the host inflammatory response directed against the parasite, a causal association between helminths and allergy remains uncertain. The present study was therefore designed to evaluate the relationship between nutritional status, parasite infection and prevalence of allergy among school children. Methods A cross sectional study was performed involving school children in two elementary schools in Gondar, Ethiopia. Nutritional status of these children was determined using anthropometric parameters (weight-for-age, height-for-age and BMI-for-age). Epi-Info software was used to calculate z-scores. Stool samples were examined using standard parasitological procedures. The serum IgE levels were quantified by total IgE ELISA kit following the manufacturer’s instruction. Result A total of 405 children (with mean age of 12.09.1 ± 2.54 years) completed a self-administered allergy questionnaire and provided stool samples for analysis. Overall prevalence of underweight, stunting and thinness/wasting was 15.1%, 25.2%, 8.9%, respectively. Of the total, 22.7% were found to be positive for intestinal parasites. The most prevalent intestinal parasite detected was Ascaris lumbricoides (31/405, 7.6%). There was no statistically significant association between prevalence of malnutrition and the prevalence of parasitic infections. Median total serum IgE level was 344 IU/ml (IQR 117–2076, n = 80) and 610 IU/ml (143–1833, n = 20), respectively, in children without and with intestinal parasite infection (Z = −0.198, P > 0.8). The prevalence of self reported allergy among the subset was 8%. IgE concentration was not associated either with the presence of parasitic infection or history of allergy. Conclusion The prevalence of malnutrition, intestinal parasitism and allergy was not negligible in this

Proteome of Aedes aegypti in response to infection and coinfection with microsporidian parasites

PubMed Central

Duncan, Alison B; Agnew, Philip; Noel, Valérie; Demettre, Edith; Seveno, Martial; Brizard, Jean-Paul; Michalakis, Yannis

2012-01-01

Hosts are frequently infected with more than one parasite or pathogen at any one time, but little is known as to how they respond to multiple immune challenges compared to those involving single infections. We investigated the proteome of Aedes aegypti larvae following infection with either Edhazardia aedis or Vavraia culicis, and coinfections involving both. They are both obligate intracellular parasites belonging to the phylum microsporidia and infect natural populations of Ae. aegypti. The results found some proteins only showing modified abundance in response to infections involving E. aedis, while others were only differentially abundant when infections involved V. culicis. Some proteins only responded with modified abundance to the coinfection condition, while others were differentially abundant in response to all three types of infection. As time since infection increased, the response to each of the single parasite infections diverged, while the response to the E. aedis and coinfection treatments converged. Some of the proteins differentially abundant in response to infection were identified. They included two vacuolar ATPases, proteins known to have a role in determining the infection success of intracellular parasites. This result suggests microsporidia could influence the infection success of other intracellular pathogens infecting vector species of mosquito, including viruses, Plasmodium and Wolbachia. PMID:22837817

Parasitic Infections in Hematopoietic Stem Cell Transplantation

PubMed Central

Jarque, Isidro; Salavert, Miguel; Pemán, Javier

2016-01-01

Parasitic infections are rarely documented in hematopoietic stem cell transplant recipients. However they may be responsible for fatal complications that are only diagnosed at autopsy. Increased awareness of the possibility of parasitic diseases both in autologous and allogeneic stem cell transplant patients is relevant not only for implementing preventive measures but also for performing an early diagnosis and starting appropriate therapy for these unrecognized but fatal infectious complications in hematopoietic transplant recipients. In this review, we will focus on parasitic diseases occurring in this population especially those with major clinical relevance including toxoplasmosis, American trypanosomiasis, leishmaniasis, malaria, and strongyloidiasis, among others, highlighting the diagnosis and management in hematopoietic transplant recipients. PMID:27413527

Women and Parasitic Diseases

MedlinePlus

... Z Index Laboratory Diagnostic Assistance Parasitic Disease and Malaria Strategic Priorities: 2015—2020 About our Division Get ... human immunodeficiency virus (HIV) infection. Pregnant women in malaria-endemic countries are at increased risk for adverse ...

MHC-I affects infection intensity but not infection status with a frequent avian malaria parasite in blue tits.

PubMed

Westerdahl, Helena; Stjernman, Martin; Råberg, Lars; Lannefors, Mimi; Nilsson, Jan-Åke

2013-01-01

Host resistance against parasites depends on three aspects: the ability to prevent, control and clear infections. In vertebrates the immune system consists of innate and adaptive immunity. Innate immunity is particularly important for preventing infection and eradicating established infections at an early stage while adaptive immunity is slow, but powerful, and essential for controlling infection intensities and eventually clearing infections. Major Histocompatibility Complex (MHC) molecules are central in adaptive immunity, and studies on parasite resistance and MHC in wild animals have found effects on both infection intensity (parasite load) and infection status (infected or not). It seems MHC can affect both the ability to control infection intensities and the ability to clear infections. However, these two aspects have rarely been considered simultaneously, and their relative importance in natural populations is therefore unclear. Here we investigate if MHC class I genotype affects infection intensity and infection status with a frequent avian malaria infection Haemoproteus majoris in a natural population of blue tits Cyanistes caeruleus. We found a significant negative association between a single MHC allele and infection intensity but no association with infection status. Blue tits that carry a specific MHC allele seem able to suppress H. majoris infection intensity, while we have no evidence that this allele also has an effect on clearance of the H. majoris infection, a result that is in contrast with some previous studies of MHC and avian malaria. A likely explanation could be that the clearance rate of avian malaria parasites differs between avian malaria lineages and/or between avian hosts.

MHC-I Affects Infection Intensity but Not Infection Status with a Frequent Avian Malaria Parasite in Blue Tits

PubMed Central

Westerdahl, Helena; Stjernman, Martin; Råberg, Lars; Lannefors, Mimi; Nilsson, Jan-Åke

2013-01-01

Host resistance against parasites depends on three aspects: the ability to prevent, control and clear infections. In vertebrates the immune system consists of innate and adaptive immunity. Innate immunity is particularly important for preventing infection and eradicating established infections at an early stage while adaptive immunity is slow, but powerful, and essential for controlling infection intensities and eventually clearing infections. Major Histocompatibility Complex (MHC) molecules are central in adaptive immunity, and studies on parasite resistance and MHC in wild animals have found effects on both infection intensity (parasite load) and infection status (infected or not). It seems MHC can affect both the ability to control infection intensities and the ability to clear infections. However, these two aspects have rarely been considered simultaneously, and their relative importance in natural populations is therefore unclear. Here we investigate if MHC class I genotype affects infection intensity and infection status with a frequent avian malaria infection Haemoproteus majoris in a natural population of blue tits Cyanistes caeruleus. We found a significant negative association between a single MHC allele and infection intensity but no association with infection status. Blue tits that carry a specific MHC allele seem able to suppress H. majoris infection intensity, while we have no evidence that this allele also has an effect on clearance of the H. majoris infection, a result that is in contrast with some previous studies of MHC and avian malaria. A likely explanation could be that the clearance rate of avian malaria parasites differs between avian malaria lineages and/or between avian hosts. PMID:24023631

Parasite-induced ER stress response in hepatocytes facilitates Plasmodium liver stage infection.

PubMed

Inácio, Patricia; Zuzarte-Luís, Vanessa; Ruivo, Margarida T G; Falkard, Brie; Nagaraj, Nagarjuna; Rooijers, Koos; Mann, Matthias; Mair, Gunnar; Fidock, David A; Mota, Maria M

2015-08-01

Upon infection of a mammalian host, Plasmodium parasites first replicate inside hepatocytes, generating thousands of new parasites. Although Plasmodium intra-hepatic development represents a substantial metabolic challenge to the host hepatocyte, how infected cells respond to and integrate this stress remains poorly understood. Here, we present proteomic and transcriptomic analyses, revealing that the endoplasmic reticulum (ER)-resident unfolded protein response (UPR) is activated in host hepatocytes upon Plasmodium berghei infection. The expression of XBP1s--the active form of the UPR mediator XBP1--and the liver-specific UPR mediator CREBH is induced by P. berghei infection in vivo. Furthermore, this UPR induction increases parasite liver burden. Altogether, our data suggest that ER stress is a central feature of P. berghei intra-hepatic development, contributing to the success of infection. © 2015 The Authors.

Intestinal Parasitic Infections among Intellectual Disability Children in Rehabilitation Centers of Northern Iran

ERIC Educational Resources Information Center

Sharif, Mehdi; Daryani, Ahmad; Asgarian, Fatemeh; Nasrolahei, Mohtaram

2010-01-01

Parasitic infection is highly prevalent throughout the developing countries of the world. These infections are the major problem in rehabilitation centers for the mentally retarded. There have been many reports about the prevalence of parasitic infection among different groups of people in Iran; however, the epidemiological data in intellectual…

Gastrointestinal parasitic infection, anthropometrics, nutritional status, and physical work capacity in Colombian boys.

PubMed

Wilson, W.M.; Dufour, D.L.; Staten, L.K.; Barac-Nieto, M.; Reina, J.C.; Spurr, G.B.

1999-11-01

This article tests the hypothesis that the presence of gastrointestinal parasites in Colombian boys is negatively associated with anthropometric characteristics, physical work capacity, blood hemoglobin (Hb) levels, and nutritional status. Anthropometric, Hb, &Vdot;O(2) max, and parasite load data were collected on 1,016 boys in Cali, Colombia. The boys were classified as lower socioeconomic class (SEC) from either urban or rural environments, and upper SEC from an urban environment. Sixty-three percent of the boys were infected with gastrointestinal parasites and, of the infected boys, 80-95% had light parasite loads. Parasites found included Necator americanus, Ascaris lumbricoides, Entamoeba histolytica, Trichuris trichiura, Giardia spp., and Enterobius vermicularis. Infected boys had significantly lower weight, stature, weight-for-height (among 6-9-year-old boys), Hb levels, and &Vdot;O(2) max (ANCOVA, controlling for age and SEC). In terms of nutritional status, infected boys were 1.47 times more likely to be classified as iron deficient than noninfected boys (chi-square, P < 0.001), and 1.61 times more likely to be classified as stunted (P < 0.001). Infection was not associated with wasting in any SEC group. In conclusion, light to moderate gastrointestinal parasite loads were associated with significantly lower weight, stature, weight-for-height (in 6-9-year-old boys), Hb levels, and &Vdot;O(2) max, and a significantly higher frequency of IDA and stunting. These data suggest that comprehensive analyses of the nutritional status of populations in regions endemic for parasitic infection should include testing for the presence of infection. Am. J. Hum. Biol. 11:763-771, 1999. Copyright 1999 Wiley-Liss, Inc.

Persistence of Plasmodium falciparum parasites in infected pregnant Mozambican women after delivery.

PubMed

Serra-Casas, Elisa; Menéndez, Clara; Dobaño, Carlota; Bardají, Azucena; Quintó, Llorenç; Quintó, Llorençc; Ordi, Jaume; Sigauque, Betuel; Cisteró, Pau; Mandomando, Inacio; Alonso, Pedro L; Mayor, Alfredo

2011-01-01

Pregnant women are susceptible to Plasmodium falciparum parasites that sequester in the placenta. The massive accumulation of infected erythrocytes in the placenta has been suggested to trigger the deleterious effects of malaria in pregnant women and their offspring. The risk of malaria is also high during the postpartum period, although mechanisms underlying this susceptibility are not known. Here, we aimed to identify host factors contributing to the risk of postpartum infections and to determine the origin of postpartum parasites by comparing their genotypes with those present at the time of delivery. To address this, blood samples were collected at delivery (n = 402) and postpartum (n = 354) from Mozambican women enrolled in a trial of intermittent preventive treatment in pregnancy (IPTp). P. falciparum was detected by real-time quantitative PCR (qPCR), and the parasite merozoite surface protein 1 (msp-1) and msp-2 genes were genotyped. Fifty-seven out of 354 (16%) women were infected postpartum as assessed by qPCR, whereas prevalence by optical microscopy was only 4%. Risk of postpartum infection was lower in older women (odds ratio [OR] = 0.34, 95% confidence interval [CI] = 0.15 to 0.81) and higher in women with a placental infection at delivery (OR = 4.20, 95% CI = 2.19 to 8.08). Among 24 women with matched infections, 12 (50%) were infected postpartum with at least one parasite strain that was also present in their placentas. These results suggest that parasites infecting pregnant women persist after delivery and increase the risk of malaria during the postpartum period. Interventions that reduce malaria during pregnancy may translate into a lower risk of postpartum infection.

Intestinal parasitic infections: Current prevalence and risk factors among schoolchildren in capital area of the Republic of Marshall Islands.

PubMed

Liao, Chien-Wei; Chuang, Ting-Wu; Huang, Ying-Chieh; Chou, Chia-Mei; Chiang, Chia-Lien; Lee, Fei-Peng; Hsu, Yun-Ting; Lin, Jia-Wei; Briand, Kennar; Tu, Chia-Ying; Fan, Chia-Kwung

2017-12-01

Intestinal parasitic infections (IPIs) among schoolchildren in Republic of Marshall Islands (RMI) largely remains unknown, thus investigation on IPIs status to establish the baseline data is urgently needed. This cross-sectional study intended to investigate the current IPIs status and associated risk factors among schoolchildren at capital of RMI. Single stool sample from 400 schoolchildren (207 boys and 193 girls) aged 9.73±2.50 yrs old was examined by employing merthiolate-iodine-formaldehyde concentration method. Demographic characteristics, uncomfortable symptoms and risk factors were obtained by questionnaires investigation. The overall prevalence of IPIs in schoolchildren was 22.8% (91/400), of them 24.2% harbored at least 2 different parasites. Notably, the majority was infected by waterborne protozoan parasites (82.4%, 75/91). Nine different intestinal parasites have been identified, of which six were pathogenic including Hook worm, Trichuris trichiura, Enterobius vermicularis, Entamoeba histolytica/dispar, Giardia intestinalis and Blastocystis hominis. Schoolchildren who ever complained dizziness or headache showed a significant higher prevalence of pathogenic IPIs than those who did not (p<0.05). Schoolchildren who lived in urban area than rural area had higher chance to acquire pathogenic IPIs (p=0.03). However, none of risk factors were identified to be associated with pathogenic IPIs. Copyright © 2017 Elsevier B.V. All rights reserved.

Age as a factor in acquisition of parasites by Canada geese

USGS Publications Warehouse

Wehr, E.E.; Herman, C.M.

1954-01-01

Examination of 46 Canada goose goslings yielded 14 species of parasites, including five Protozoa, four Nematoda, two Cestoda, and three Trematoda. Evidence indicates that goslings acquired most of these infections during their first week of life. Some parasites, Prosthogonimus sp., occurred only in younger birds. Others, Leucocytozoon simondi, were evident only during the initial course of infection, while still others remained evident in older geese. Parasites with a direct life cycle appeared to be more prevalent than those requiring intermediate hosts. Among 29 birds from a refuge in Michigan, 14 species of parasites were found; while in 17 goslings from a Utah refuge, only five species occurred.

Occurrence of enteric parasitic infections among HIV-infected individuals and its relation to CD4 T-cell counts with a special emphasis on coccidian parasites at a tertiary care centre in South India.

PubMed

Swathirajan, Chinnambedu R; Vignesh, Ramachandran; Pradeep, Ambrose; Solomon, Sunil S; Solomon, Suniti; Balakrishnan, Pachamuthu

2017-01-01

Diarrhoea is one of the major complications occurring in over 90% of HIV-infected individuals in developing countries. Coccidian group of parasites, being opportunistic pathogens, have been implicated as the most common causative agents of diarrhoea among HIV-infected population. The aim was to study the magnitude of parasitic diarrhoea with special context to coccidian parasitic infections in HIV-infected individuals and their association with the patient's immunological status measured by CD4 T-cell counts. This investigation was performed between January 2002 and December 2014 at a tertiary HIV care centre in Chennai, South India. Stool samples were collected and microscopically observed for parasites using direct, formal-ether-concentrated wet mounts and modified acid-fast staining for coccidian parasites. CD4 T-cell counts were done by FACScount. All statistical analyses were performed using GraphPad Prism software, version 5.0, andP < 0.05 was considered statistically significant. Coccidian parasitic infection accounted for about 23.4% of parasitic infections, and of these, Cystoisospora belli was observed to be the most common cause of diarrhoea (88.8%), followed by Cryptosporidium spp. (9.9%) and Cyclospora spp. (1.3%). Trend analysis of coccidian aetiology during the study period revealed a significant rise in the positivity of C. belli and Cryptosporidium spp. (P = 0.001). Among the HIV patients with CD4+ T-cell counts <200 cells/μL, Cryptosporidium infection was most common (90%), followed by infection with C. belli(61.4%). Coccidian parasites continue to be the most common aetiological agent of diarrhoea among patients with HIV. The increasing trend of positivity of both cystoisosporiasis and cryptosporidiosis over the study period and the high positivity of cryptosporidiosis in patients with lower CD4+ T-cell counts are issues of serious concern. The findings call for the need for the early diagnosis of coccidian parasites and appropriate intervention

Control of intestinal parasitic infections in Seychelles: a comprehensive and sustainable approach.

PubMed Central

Albonico, M.; Shamlaye, N.; Shamlaye, C.; Savioli, L.

1996-01-01

Intestinal parasitic infections have been perceived as a public health problem in Seychelles for decades. A comprehensive strategy to reduce morbidity and, in the long term, transmission of intestinal parasites has been implemented successfully since 1993. Management of the programme is integrated into the well established primary health care system, with control activities being undertaken through existing health facilities. The strategy is based on periodic chemotherapy of schoolchildren, intense health education and improvement of sanitation and safe water supply. The initial objectives of the control programme were met after 2 years of activities, with an overall reduction in prevalence of intestinal parasitic infections of 44%. The intensity of infection with Trichuris trichiura, the commonest parasite, was halved (from 780 to 370 eggs per g of faeces). The programme's integrated approach, in concert with political commitment and limited operational costs, is a warranty for the future sustainability of control activities. The programme can be seen as a model for other developing countries, even where health and socioeconomic conditions are different and the control of parasitic infections will need a much longer-term commitment. PMID:9060217

Parasite-induced ER stress response in hepatocytes facilitates Plasmodium liver stage infection

PubMed Central

Inácio, Patricia; Zuzarte-Luís, Vanessa; Ruivo, Margarida TG; Falkard, Brie; Nagaraj, Nagarjuna; Rooijers, Koos; Mann, Matthias; Mair, Gunnar; Fidock, David A; Mota, Maria M

2015-01-01

Upon infection of a mammalian host, Plasmodium parasites first replicate inside hepatocytes, generating thousands of new parasites. Although Plasmodium intra-hepatic development represents a substantial metabolic challenge to the host hepatocyte, how infected cells respond to and integrate this stress remains poorly understood. Here, we present proteomic and transcriptomic analyses, revealing that the endoplasmic reticulum (ER)-resident unfolded protein response (UPR) is activated in host hepatocytes upon Plasmodium berghei infection. The expression of XBP1s—the active form of the UPR mediator XBP1—and the liver-specific UPR mediator CREBH is induced by P. berghei infection in vivo. Furthermore, this UPR induction increases parasite liver burden. Altogether, our data suggest that ER stress is a central feature of P. berghei intra-hepatic development, contributing to the success of infection. PMID:26113366

The three-spined stickleback-Schistocephalus solidus system: an experimental model for investigating host-parasite interactions in fish.

PubMed

Barber, I; Scharsack, J P

2010-03-01

Plerocercoids of the pseudophyllidean cestode Schistocephalus solidus infect the three-spined stickleback Gasterosteus aculeatus, with important consequences for the biology of host fish. Techniques for culturing the parasite in vitro and generating infective stages that can be used to infect sticklebacks experimentally have been developed, and the system is increasingly used as a laboratory model for investigating aspects of host-parasite interactions. Recent experimental laboratory studies have focused on the immune responses of hosts to infection, the consequences of infection for the growth and reproductive development of host fish and the effects of infection on host behaviour. Here we introduce the host and the parasite, review the major findings of these recent experimental infection studies and identify further aspects of host parasite interactions that might be investigated using the system.

Intestinal Parasitic Infections among Pregnant Women in Venezuela

PubMed Central

Rodríguez-Morales, Alfonso J.; Barbella, Rosa A.; Case, Cynthia; Arria, Melissa; Ravelo, Marisela; Perez, Henry; Urdaneta, Oscar; Gervasio, Gloria; Rubio, Nestor; Maldonado, Andrea; Aguilera, Ymora; Viloria, Anna; Blanco, Juan J.; Colina, Magdary; Hernández, Elizabeth; Araujo, Elianet; Cabaniel, Gilberto; Benitez, Jesús; Rifakis, Pedro

2006-01-01

Introduction. Intestinal parasitic infections, especially due to helminths, increase anemia in pregnant women. The results of this are low pregnancy weight gain and IUGR, followed by LBW, with its associated greater risks of infection and higher perinatal mortality rates. For these reasons, in the setting of no large previous studies in Venezuela about this problem, a national multicentric study was conducted. Methods. Pregnant women from nine states were studied, a prenatal evaluation with a coproparasitological study. Univariated and multivariated analyses were made to determine risk factors for intestinal parasitosis and related anemia. Results. During 19 months, 1038 pregnant women were included and evaluated. Intestinal parasitosis was evidenced in 73.9%: A lumbricoides 57.0%, T trichiura 36.0%, G lamblia 14.1%, E hystolitica 12.0%, N americanus 8.1%, E vermicularis 6.3%, S stercoralis 3.3%. Relative risk for anemia in those women with intestinal parasitosis was 2.56 (P < .01). Discussion. Intestinal parasitoses could be associated with conditions for development of anemia at pregnancy. These features reflect the need of routine coproparasitological study among pregnant women in rural and endemic zones for intestinal parasites. Further therapeutic and prophylactic protocols are needed. Additional research on pregnant intestinal parasitic infection impact on newborn health is also considered. PMID:17093349

Smelling fit: scent marking exposes parasitic infection status in the banded mongoose.

PubMed

Mitchell, Jessica; Cant, Michael A; Vitikainen, Emma I K; Nichols, Hazel J

2017-06-01

Preference for uninfected mates is presumed beneficial as it minimizes one's risk of contracting an infection and infecting one's offspring. In avian systems, visual ornaments are often used to indicate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where experimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load (estimated using fecal egg counts) and scent marking behavior in a wild population of banded mongooses Mungos mungo . Focusing on a costly protozoan parasite of the genus Isospora and the nematode worm Toxocara , we first show that banded mongooses that engage in frequent, intensive scent marking have lower Isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high Isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.

Effect of tourism and trade on intestinal parasitic infections in Guatemala.

PubMed

Jensen, L A; Marlin, J W; Dyck, D D; Laubach, H E

2009-04-01

A survey was performed to determine if infection with gastrointestinal parasites differs between the rural and urban poor inhabitants of Guatemala. A total of 317 stool samples from children in two towns, one rural and one urban, were examined using the formalin-ether concentration method. The overall prevalence of parasites in infected children was 67%, 20%, 30%, and 22%, respectively for Ascaris lumbricoides, Trichuris trichiura, Giardia duodenalis and Entamoeba histolytica in the rural town of La Mano de Leon and 49%, 14%, 15%, and 21%, respectively in the urban town of Santa Maria de Jesus. Two sub-studies were carried out to determine the effects of (1) gender and (2) age on the rate of parasitic infections. Female children in the 1-to 6-year-olds age group in Santa Maria de Jesus had more infections with A. lumbricoides and T. trichiura when compared to La Mano de Leon. A. lumbricoides was most prevalent in Santa Maria de Jesus. These results propose that accessibility to tourism and trade decreases the risk for the establishment of parasitic diseases in children of Guatemala possibly due to improvements in basic nutrition and availability of health care.

Carotenoid-based bill colour is an integrative signal of multiple parasite infection in blackbird

NASA Astrophysics Data System (ADS)

Biard, Clotilde; Saulnier, Nicolas; Gaillard, Maria; Moreau, Jérôme

2010-11-01

In the study of parasite-mediated sexual selection, there has been controversial evidence for the prediction that brighter males should have fewer parasites. Most of these studies have focused on one parasite species. Our aim was to investigate the expression of carotenoid-based coloured signals in relation to patterns of multiple parasite infections, to determine whether colour reflects parasite load of all parasite species, or whether different relationships might be found when looking at each parasite species independently. We investigated the relationship between bill colour, body mass and plasma carotenoids and parasite load (feather chewing lice, blood parasite Plasmodium sp., intestinal parasites cestodes and coccidia) in the blackbird ( Turdus merula). Bill colour on its own appeared to be a poor predictor of parasite load when investigating its relationships with individual parasite species. Variation in parasite intensities at the community level was summarised using principal component analysis to derive synthetic indexes of relative parasite species abundance and absolute parasite load. The relative abundance of parasite species was strongly related to bill colour, plasma carotenoid levels and body mass: birds with relatively more cestodes and chewing lice and relatively less Plasmodium and coccidia had a more colourful bill, circulated more carotenoids and were heavier. These results suggest that bill colour more accurately reflects the relative intensities of parasite infection, rather than one-by-one relationships with parasites or absolute parasite burden. Investigating patterns of multiple parasite infection would thus improve our understanding of the information conveyed by coloured signals on parasite load.

Intestinal parasitic infections in Iranian preschool and school children: A systematic review and meta-analysis.

PubMed

Daryani, Ahmad; Hosseini-Teshnizi, Saeed; Hosseini, Seyed-Abdollah; Ahmadpour, Ehsan; Sarvi, Shahabeddin; Amouei, Afsaneh; Mizani, Azadeh; Gholami, Sara; Sharif, Mehdi

2017-05-01

Parasitic infections are a serious public health problem because they cause anemia, growth retardation, aggression, weight loss, and other physical and mental health problems, especially in children. Numerous studies have been performed on intestinal parasitic infections in Iranian preschool and school children. However, no study has gathered and analyzed this information systematically. The aim of this study was to provide summary estimates for the available data on intestinal parasitic infections in Iranian children. We searched 9 English and Persian databases, unpublished data, abstracts of scientific congresses during 1996-2015 using the terms intestinal parasite, Giardia, Cryptosporidium, Enterobiusvermicularis, oxyure, school, children, preschool, and Iran. We conducted meta-analysis using STATA, and for all statistical tests, p-value less than 0.05was considered significant. Among the 68,532 publications searched as a result, 103 were eligible for inclusion in the study. The prevalence rate of intestinal parasitic infections was 38% (95% CI- 33%, 43%). Prevalence of protozoa, helminthic intestinal infections, and non-pathogenic parasites was 16.9%, 9.48%, and 18.5%, respectively, which affected 14.27% males and 15.3% females. The rate of infection in preschool and school children was 38.19% and 43.37% respectively. Giardia, Enterobiusvermicularis and Entamoeba coli were the most common among protozoa, helminthic, and non-pathogenic infections (15.1%, 16.5%, and 7.1%, respectively). The data analyses indicated that the prevalence of intestinal parasitic infection is decreasing in Iranian preschool and school children. Improvement of sanitation, personal hygiene, increased awareness of people, seasonal variations, and health education can be effective in reducing parasitic infections in different communities. Copyright © 2017. Published by Elsevier B.V.

Secondary Defense Chemicals in Milkweed Reduce Parasite Infection in Monarch Butterflies, Danaus plexippus.

PubMed

Gowler, Camden D; Leon, Kristoffer E; Hunter, Mark D; de Roode, Jacobus C

2015-06-01

In tri-trophic systems, herbivores may benefit from their host plants in fighting parasitic infections. Plants can provide parasite resistance in two contrasting ways: either directly, by interfering with the parasite, or indirectly, by increasing herbivore immunity or health. In monarch butterflies, the larval diet of milkweed strongly influences the fitness of a common protozoan parasite. Toxic secondary plant chemicals known as cardenolides correlate strongly with parasite resistance of the host, with greater cardenolide concentrations in the larval diet leading to lower parasite growth. However, milkweed cardenolides may covary with other indices of plant quality including nutrients, and a direct experimental link between cardenolides and parasite performance has not been established. To determine if the anti-parasitic activity of milkweeds is indeed due to secondary chemicals, as opposed to nutrition, we supplemented the diet of infected and uninfected monarch larvae with milkweed latex, which contains cardenolides but no nutrients. Across three experiments, increased dietary cardenolide concentrations reduced parasite growth in infected monarchs, which consequently had longer lifespans. However, uninfected monarchs showed no differences in lifespan across treatments, confirming that cardenolide-containing latex does not increase general health. Our results suggest that cardenolides are a driving force behind plant-derived resistance in this system.

From Parasite Encounter to Infection: Multiple-Scale Drivers of Parasite Richness in a Wild Social Primate Population

NASA Technical Reports Server (NTRS)

Benavides J. A.; Huchard, E.; Pettorelli, N.; King, A. J.; Brown, M. E.; Archer, C. E.; Appleton, C. C.; Raymond, M.; Cowlishaw, G.

2011-01-01

Host parasite diversity plays a fundamental role in ecological and evolutionary processes, yet the factors that drive it are still poorly understood. A variety of processes, operating across a range of spatial scales, are likely to influence both the probability of parasite encounter and subsequent infection. Here, we explored eight possible determinants of parasite richness, comprising rainfall and temperature at the population level, ranging behavior and home range productivity at the group level, and age, sex, body condition, and social rank at the individual level. We used a unique dataset describing gastrointestinal parasites in a terrestrial subtropical vertebrate (chacma baboons, Papio ursinus), comprising 662 faecal samples from 86 individuals representing all age-sex classes across two groups over two dry seasons in a desert population. Three mixed models were used to identify the most important factor at each of the three spatial scales (population, group, individual); these were then standardised and combined in a single, global, mixed model. Individual age had the strongest influence on parasite richness, in a convex relationship. Parasite richness was also higher in females and animals in poor condition, albeit at a lower order of magnitude than age. Finally, with a further halving of effect size, parasite richness was positively correlated to day range and temperature. These findings indicate that a range of factors influence host parasite richness through both encounter and infection probabilities, but that individual-level processes may be more important than those at the group or population level.

Lesser snow goose helminths show recurring and positive parasite infection-diversity relations.

PubMed

Dargent, Felipe; Morrill, André; Alisauskas, Ray T; McLaughlin, J Daniel; Shutler, Dave; Forbes, Mark R

2017-04-01

The patterns and mechanisms by which biological diversity is associated with parasite infection risk are important to study because of their potential implications for wildlife population's conservation and management. Almost all research in this area has focused on host species diversity and has neglected parasite diversity, despite evidence that parasites are important drivers of community structure and ecosystem processes. Here, we assessed whether presence or abundance of each of nine helminth species parasitizing lesser snow geese ( Chen caerulescens ) was associated with indices of parasite diversity (i.e. species richness and Shannon's Diversity Index). We found repeated instances of focal parasite presence and abundance having significant positive co-variation with diversity measures of other parasites. These results occurred both within individual samples and for combinations of all samples. Whereas host condition and parasite facilitation could be drivers of the patterns we observed, other host- or parasite-level effects, such as age or sex class of host or taxon of parasite, were discounted as explanatory variables. Our findings of recurring and positive associations between focal parasite abundance and diversity underscore the importance of moving beyond pairwise species interactions and contexts, and of including the oft-neglected parasite species diversity in infection-diversity studies.

Prevalence of Intestinal Parasitic Infections and their Association with Nutritional Status of Rural and Urban Pre-School Children in Benue State, Nigeria.

PubMed

Tyoalumun, Kpurkpur; Abubakar, Sani; Christopher, Nongu

2016-01-01

Intestinal parasitic infections are highly prevalent in developing countries, contributing to high incidence of malnutrition and morbidity. This study aimed to find the prevalence of intestinal parasitic infections and their association with nutritional status of children in Benue State, Nigeria. A cross sectional study conducted from January-June 2016, among 418 school children under-5 years of age. Anthropometric data, height-for-age, weight-for-height, and weight-for-age Z-scores from each child and fecal samples were collected and screened for intestinal parasites using standard laboratory methods. Among the intestinal parasitic infections detected, the prevalence of E. histolytica was higher (51.0% and 29.0%) than all other parasites encountered in rural and urban pupils (P<0.05). Other parasites were Hookworm (46.2% and 24.8%); G. lamblia (11.5% and 8.6%); and T. trichiura (2.4% and 5.2%). The prevalence of stunting (HAZ<-2), in rural and urban pupils were 43.8% and 32.9%; 64.4% and 39.0% rural and urban pupils were underweight (WAZ<-2), while 30.3% and 24.3% were wasted (WHZ<-2). Infected children had significantly (P<0.05) higher z-scores than the uninfected children. Benue State is among the Nigerian states with the highest burden of tropical diseases with a current plan of elimination implemented through mass drug administration. This study identify/evaluate some essential information that will support the planning and implementation of the State's ongoing efforts.

Co-infection of tuberculosis and parasitic diseases in humans: a systematic review

PubMed Central

2013-01-01

Co-infection of tuberculosis and parasitic diseases in humans is an important public problem in co-endemic areas in developing countries. However, there is a paucity of studies on co-infection and even fewer reviews. This review examines 44 appropriate papers by PRISMA from 289 papers searched in PubMed via the NCBI Entrez system (no grey literature) up to December 2012 in order to analyze the factors that influence epidemic and host’s immunity of co-infection. The limited evidence in this review indicates that most common parasite species are concurrent with Mycobacterium tuberculosis in multiple organs; socio-demographics such as gender and age, special populations with susceptibility such as renal transplant recipients, patients on maintenance haemodialysis, HIV positive patients and migrants, and living in or coming from co-endemic areas are all likely to have an impact on co-infection. Pulmonary tuberculosis and parasitic diseases were shown to be risk factors for each other. Co-infection may significantly inhibit the host’s immune system, increase antibacterial therapy intolerance and be detrimental to the prognosis of the disease; in addition, infection with parasitic diseases can alter the protective immune response to Bacillus Calmette-Guerin vaccination against Mycobacterium tuberculosis. PMID:23522098

Haemosporidian parasite infections in grouse and ptarmigan: Prevalence and genetic diversity of blood parasites in resident Alaskan birds

USGS Publications Warehouse

Smith, Matthew M.; Van Hemert, Caroline R.; Merizon, Richard

2016-01-01

Projections related to future climate warming indicate the potential for an increase in the distribution and prevalence of blood parasites in northern regions. However, baseline data are lacking for resident avian host species in Alaska. Grouse and ptarmigan occupy a diverse range of habitat types throughout the northern hemisphere and are among the most well-known and important native game birds in North America. Information regarding the prevalence and diversity of haemosporidian parasites in tetraonid species is limited, with few recent studies and an almost complete lack of genetic data. To better understand the genetic diversity of haemosporidian parasites in Alaskan tetraonids and to determine current patterns of geographic range and host specificity, we used molecular methods to screen 459 tissue samples collected from grouse and ptarmigan species across multiple regions of Alaska for infection by Leucocytozoon, Haemoproteus, and Plasmodium blood parasites. Infections were detected in 342 individuals, with overall apparent prevalence of 53% for Leucocytozoon, 21% for Haemoproteus, and 9% for Plasmodium. Parasite prevalence varied by region, with different patterns observed between species groups (grouse versus ptarmigan). Leucocytozoon was more common in ptarmigan, whereas Haemoproteus was more common in grouse. We detected Plasmodium infections in grouse only. Analysis of haemosporidian mitochondrial DNA cytochrome b sequences revealed 23 unique parasite haplotypes, several of which were identical to lineages previously detected in other avian hosts. Phylogenetic analysis showed close relationships between haplotypes from our study and those identified in Alaskan waterfowl for Haemoproteus and Plasmodium parasites. In contrast, Leucocytozoon lineages were structured strongly by host family. Our results provide some of the first genetic data for haemosporidians in grouse and ptarmigan species, and provide an initial baseline on the prevalence and diversity

Helminth parasitic infections of the central nervous system: a diagnostic approach.

PubMed

Othman, Ahmad A; Bruschi, Fabrizio; Ganna, Ahmed A

2014-04-01

Helminth parasitic infections of the central nervous system (CNS) occur worldwide with high prevalence in tropical and subtropical countries. Clinical evaluation of patients is mandatory, and it is convenient to group the clinical manifestations into syndromes: for example space-occupying lesions, meningitis, and encephalitis. The history should focus on residence or travel to endemic areas, diet, activities, intercurrent medical conditions, and associated clinical clues. Direct parasitological diagnosis can be reached by cerebrospinal fluid and cerebral tissue examination either by microscopy, culture, or immunological techniques. Immunodiagnosis by detection of parasite antibodies or antigens in serum could provide indirect evidence of parasitic infections. In addition, various imaging and radiological techniques e.g., computed tomography (CT) scan and magnetic resonance imaging (MRI) complement the diagnostic work-up of CNS diseases. Finally, the helminthic CNS infections of global impact, such as schistosomiasis, neurotoxocariasis, Strongyloides infection, neurotrichinosis, neurocysticercosis, and echinococcosis will be briefly discussed as regards the principal clinical and diagnostic features.

Association between parasitic infections and tuberculin skin test results in refugees.

PubMed

Watts, Nathaniel S; Mizinduko, Mucho M; Barnett, Elizabeth D; White, Laura F; Hochberg, Natasha S

Parasitic infections are known to modulate the immune response necessary for controlling Mycobacterium tuberculosis infection. We sought to investigate species-specific effects of parasite infection on M. tuberculosis infection. As part of the Refugee Health Assessment Program, stool examinations and tuberculin skin testing were performed on refugees seen at Boston Medical Center between 1995 and 2012. Tuberculin skin test (TST) and stool examination data were collected for 6669 refugees; 3349 (50.2%) were TST positive (≥10 mm). Among TST-positive subjects, 176 (5.3%) had helminth infections and 1149 (34.3%) protozoa. After adjusting for sex, age, and country of origin, helminth and protozoan infections were not associated with TST-positivity. When species-specific effects were examined, subjects infected with Trichuris trichiura and Giardia lamblia had reduced odds of TST-positivity (adjusted OR [aOR] 0.65 [95%CI 0.44-0.96; p = 0.03] and aOR 0.79 [95%CI 0.65-0.95, p = 0.01], respectively). Our findings suggest that T. trichiura and G. lamblia may provide protection against M. tuberculosis infection. This study adds to a growing body of literature suggesting that immune response modulation and susceptibility to M. tuberculosis infection is parasite species-dependent. Copyright © 2017 Elsevier Ltd. All rights reserved.

An Overview of Trypanosoma brucei Infections: An Intense Host-Parasite Interaction.

PubMed

Ponte-Sucre, Alicia

2016-01-01

Trypanosoma brucei rhodesiense and T. brucei gambiense , the causative agents of Human African Trypanosomiasis, are transmitted by tsetse flies. Within the vector, the parasite undergoes through transformations that prepares it to infect the human host. Sequentially these developmental stages are the replicative procyclic (in which the parasite surface is covered by procyclins) and trypo-epimastigote forms, as well as the non-replicative, infective, metacyclic form that develops in the vector salivary glands. As a pre-adaptation to their life in humans, metacyclic parasites begin to express and be densely covered by the Variant Surface Glycoprotein (VSG). Once the metacyclic form invades the human host the parasite develops into the bloodstream form. Herein the VSG triggers a humoral immune response. To avoid this humoral response, and essential for survival while in the bloodstream, the parasite changes its cover periodically and sheds into the surroundings the expressed VSG, thus evading the consequences of the immune system activation. Additionally, tools comparable to quorum sensing are used by the parasite for the successful parasite transmission from human to insect. On the other hand, the human host promotes clearance of the parasite triggering innate and adaptive immune responses and stimulating cytokine and chemokine secretion. All in all, the host-parasite interaction is extremely active and leads to responses that need multiple control sites to develop appropriately.

Immunodetection of Fasciola gigantica Circulating Antigen in Sera of Infected Individuals for Laboratory Diagnosis of Human Fascioliasis

PubMed Central

Attallah, Abdelfattah M.; Bughdadi, Faisal A.; El-Shazly, Atef M.

2013-01-01

Currently, the laboratory diagnosis of human fascioliasis is based on the parasitological examination of parasite eggs in stool specimens and serological detection of specific antibodies in serum samples, which are often unreliable diagnostic approaches. Ideally, a sensitive and specific diagnostic test for Fasciola infection should be based on the detection of circulating Fasciola antigen, which implies active infection. Here, a 27-kDa-molecular-mass antigen was identified in a Fasciola gigantica adult worm antigen preparation, excretory-secretory products, and sera from F. gigantica-infected individuals, and it was not detected in antigenic extracts of other parasites and sera from noninfected individuals. The target antigen was isolated and partially characterized as a protein. Immunoperoxidase staining located the target epitope within teguments and guts of F. gigantica adult worms. The performance characteristics of a newly developed enzyme-linked immunosorbent assay (ELISA) based on F. gigantica circulating antigen detection in serum (FgCA-27 ELISA) were investigated using sera of 120 parasitologically diagnosed F. gigantica-infected individuals and 80 noninfected individuals. The area under the receiving operating characteristic (ROC) curve (AUC) for ELISA was significantly high (AUC = 0.961, P < 0.0001) for discriminating Fasciola-infected and noninfected individuals. The developed assay showed high degrees of sensitivity, specificity, and efficiency (>93%), and a significant correlation (r = 0.715, P < 0.0001) between antigen level and parasite egg count was shown. In conclusion, a 27-kDa Fasciola antigen was identified in sera of F. gigantica-infected individuals. A highly sensitive and specific Fasciola antigen detection assay, FgCA-27 ELISA, was developed for laboratory diagnosis of human fascioliasis. PMID:23945158

Immunodetection of Fasciola gigantica circulating antigen in sera of infected individuals for laboratory diagnosis of human fascioliasis.

PubMed

Attallah, Abdelfattah M; Bughdadi, Faisal A; El-Shazly, Atef M; Ismail, Hisham

2013-10-01

Currently, the laboratory diagnosis of human fascioliasis is based on the parasitological examination of parasite eggs in stool specimens and serological detection of specific antibodies in serum samples, which are often unreliable diagnostic approaches. Ideally, a sensitive and specific diagnostic test for Fasciola infection should be based on the detection of circulating Fasciola antigen, which implies active infection. Here, a 27-kDa-molecular-mass antigen was identified in a Fasciola gigantica adult worm antigen preparation, excretory-secretory products, and sera from F. gigantica-infected individuals, and it was not detected in antigenic extracts of other parasites and sera from noninfected individuals. The target antigen was isolated and partially characterized as a protein. Immunoperoxidase staining located the target epitope within teguments and guts of F. gigantica adult worms. The performance characteristics of a newly developed enzyme-linked immunosorbent assay (ELISA) based on F. gigantica circulating antigen detection in serum (FgCA-27 ELISA) were investigated using sera of 120 parasitologically diagnosed F. gigantica-infected individuals and 80 noninfected individuals. The area under the receiving operating characteristic (ROC) curve (AUC) for ELISA was significantly high (AUC = 0.961, P < 0.0001) for discriminating Fasciola-infected and noninfected individuals. The developed assay showed high degrees of sensitivity, specificity, and efficiency (>93%), and a significant correlation (r = 0.715, P < 0.0001) between antigen level and parasite egg count was shown. In conclusion, a 27-kDa Fasciola antigen was identified in sera of F. gigantica-infected individuals. A highly sensitive and specific Fasciola antigen detection assay, FgCA-27 ELISA, was developed for laboratory diagnosis of human fascioliasis.

Carotenoid-dependent coloration of male American kestrels predicts ability to reduce parasitic infections

NASA Astrophysics Data System (ADS)

Dawson, Russell D.; Bortolotti, Gary R.

2006-12-01

The signaling function of sexually selected traits, such as carotenoid-dependent avian plumage coloration, has received a great deal of recent attention especially with respect to parasitism and immunocompetence. We argue that parasite-mediated models of sexual selection may have an implicit temporal component that many researchers have ignored. For example, previous studies have demonstrated that carotenoid-dependent traits can signal past parasite exposure, current levels of parasitism, or the ability of individuals to manage parasitic infections in the future. We examined repeated measures of carotenoid-dependent skin color and blood parasitism in American kestrels ( Falco sparverius) to distinguish whether coloration might signal current parasitism or the potential to deal with infections in the future. We found no evidence that coloration was related to current levels of parasitism in either sex. However, coloration of males significantly predicted their response to parasitism; males with bright orange coloration during prelaying, when mate choice is occurring, were more likely than dull yellow males to reduce their levels of infection by the time incubation began. Coloration during prelaying may advertise a male’s health later in the breeding season. For kestrels, the ability to predict future health would be highly beneficial given the male’s role in providing food to his mate and offspring. Coloration of females was not a significant predictor of parasitism in the future, and we provide several possible explanations for this result.

Prevalence and Risk Factors of Intestinal Parasite Infection among Schoolchildren in the Peripheral Highland Regions of Huanuco, Peru

PubMed Central

Choi, Byungjin; Kim, Bongyoung

2017-01-01

Objectives Schoolchildren in developing countries are at greater risk of intestinal parasitic infections. This study aimed to estimate the prevalence and assess the risk factors of intestinal parasite infection among schoolchildren in rural areas of Peru. Methods A volunteer team from the Korea International Cooperation Agency (KOICA) conducted a campaign for parasite eradication called “Chao parasitos” at five schools in the peripheral highland regions of Huanuco in October 2013. The study collected questionnaires and stool samples from children of participating schools. Entamoeba coli, Iodamoeba buschii, and Chilomastix mesnil were classified as nonpathogenic parasites. Results The overall prevalence of intestinal parasite infection in the students was 100% (185/185). Among them, 25.9% (48/185) were infected only with nonpathogenic parasites whereas 74.1% (137/185) were infected with at least one pathogenic parasite. Ascaris lumbricoides was the most commonly detected (37.3%, 69/185), followed by Giardia lamblia (15.1%, 28/185) and I. buschii (11.9%, 22/185). Among lifestyle practices associated with parasitic infection, the rate of washing hands before meals was significantly lower in the students with pathogenic parasites compared to those with nonpathogenic parasites (77.4%, 106/137 vs. 93.8%, 45/48, p = 0.025). Conclusion The prevalence of intestinal parasite was 100%. Both personal hygiene and water supply facilities are required to eradicate parasite infection in rural areas of Peru. PMID:29164041

Prevalence and Risk Factors of Intestinal Parasite Infection among Schoolchildren in the Peripheral Highland Regions of Huanuco, Peru.

PubMed

Choi, Byungjin; Kim, Bongyoung

2017-10-01

Schoolchildren in developing countries are at greater risk of intestinal parasitic infections. This study aimed to estimate the prevalence and assess the risk factors of intestinal parasite infection among schoolchildren in rural areas of Peru. A volunteer team from the Korea International Cooperation Agency (KOICA) conducted a campaign for parasite eradication called "Chao parasitos" at five schools in the peripheral highland regions of Huanuco in October 2013. The study collected questionnaires and stool samples from children of participating schools. Entamoeba coli , Iodamoeba buschii , and Chilomastix mesnil were classified as nonpathogenic parasites. The overall prevalence of intestinal parasite infection in the students was 100% (185/185). Among them, 25.9% (48/185) were infected only with nonpathogenic parasites whereas 74.1% (137/185) were infected with at least one pathogenic parasite. Ascaris lumbricoides was the most commonly detected (37.3%, 69/185), followed by Giardia lamblia (15.1%, 28/185) and I. buschii (11.9%, 22/185). Among lifestyle practices associated with parasitic infection, the rate of washing hands before meals was significantly lower in the students with pathogenic parasites compared to those with nonpathogenic parasites (77.4%, 106/137 vs. 93.8%, 45/48, p = 0.025). The prevalence of intestinal parasite was 100%. Both personal hygiene and water supply facilities are required to eradicate parasite infection in rural areas of Peru.

Correlation between iron deficiency anemia and intestinal parasitic infection in school-age children in Medan

NASA Astrophysics Data System (ADS)

Darlan, D. M.; Ananda, F. R.; Sari, M. I.; Arrasyid, N. K.; Sari, D. I.

2018-03-01

Anemia is an abnormal hemoglobin concentration in blood that impacts almost 40% school-age children in developing countries. Intestinal parasitic infection, along with malnutrition are contributed to influence absorption, transportation, and metabolism of iron which is the most common etiology of anemia in school-age children. The purpose of this study was to determine whether there is a correlation between iron deficiency anemia (IDA) and parasitic intestinal infection generally and protozoa infection particularly among school-age children in Medan. This was a cross-sectional study conducted from May until October 2016 in primaryschool in Medan and Hamparan Perak, Deli Serdang. Consecutive sampling was used with total 132 samples obtained. Univariate analysis and Bivariate analysis were performed.This study showed the prevalence of IDA was 7.6%, and proportion of parasitic intestinal infection was 26.5% with 19.8% protozoa infection. The correlation between IDA and intestinal parasitic infection was not significant in Chi-Square Test (p-value: 0.089), neither was between IDA and protozoa infection (p-value: 0.287). There was a correlation between MCV, MCH, and anemia with p-value<0.05. However, there was no correlation among other IDA variables such as Serum Iron, TIBC, ferritin, related to age, anemia, parasitic infection, and protozoa infection (p-value>0.05).

Infection of juvenile edible crabs, Cancer pagurus by a haplosporidian-like parasite.

PubMed

Thrupp, Tara J; Lynch, Sharon A; Wootton, Emma C; Malham, Shelagh K; Vogan, Claire L; Culloty, Sarah C; Rowley, Andrew F

2013-09-01

This study aimed to examine the pathobiology of a haplosporidian-like infection in juvenile (pre-recruit) edible crabs (Cancer pagurus) from two locations in South West Wales, UK. Infected crabs showed no external symptoms of the disease but dissection revealed an infected and hypertrophic antennal gland. Histological examination showed extensive parasitisation of the antennal gland overlying the hepatopancreas. Heavily infected crabs also showed the presence of parasites with morphological similarities to Haplosporidia in the labyrinth of the antennal gland and in the gills. The spread of the infection from the antennal gland to the gills suggests that these parasites are released into the haemolymph. Attempts to characterise the haplosporidian-like organism using several primers previously shown to amplify members of the phylum Haplosporidia failed. The prevalence of infection in juvenile edible crabs varied throughout the sampling period of November 2011 to July 2012 with the lowest level of ca. 15% in November peaking at 70% in March. This parasite may represent a threat to the sustainability of edible crab fisheries in this region if the damage observed in the antennal gland and gills results in host mortality. The identification of these parasites as members of the phylum Haplosporidia based on morphology alone must be seen as tentative in the absence of sequence data. Copyright © 2013 Elsevier Inc. All rights reserved.

Analysis of a summary network of co-infection in humans reveals that parasites interact most via shared resources.

PubMed

Griffiths, Emily C; Pedersen, Amy B; Fenton, Andy; Petchey, Owen L

2014-05-07

Simultaneous infection by multiple parasite species (viruses, bacteria, helminths, protozoa or fungi) is commonplace. Most reports show co-infected humans to have worse health than those with single infections. However, we have little understanding of how co-infecting parasites interact within human hosts. We used data from over 300 published studies to construct a network that offers the first broad indications of how groups of co-infecting parasites tend to interact. The network had three levels comprising parasites, the resources they consume and the immune responses they elicit, connected by potential, observed and experimentally proved links. Pairs of parasite species had most potential to interact indirectly through shared resources, rather than through immune responses or other parasites. In addition, the network comprised 10 tightly knit groups, eight of which were associated with particular body parts, and seven of which were dominated by parasite-resource links. Reported co-infection in humans is therefore structured by physical location within the body, with bottom-up, resource-mediated processes most often influencing how, where and which co-infecting parasites interact. The many indirect interactions show how treating an infection could affect other infections in co-infected patients, but the compartmentalized structure of the network will limit how far these indirect effects are likely to spread.

ELISA and some biochemical tests of heterophyidae infection in laboratory animals.

PubMed

El-Seify, Mahmoud A; El-Bahy, Nasr M; Desouky, Abdelrazek Y; Bazh, Eman K

2012-02-01

Heterophyiasis is an important food-borne parasitic zoonosis in Egypt, among the inhabitants living around brackish-water lakes especially fishermen, and it is a common human parasite in the Nile Delta. The experiment was done on two laboratory animals (rats and dogs), and the time of sample collection was done periodically at 6, 9, 15, 21, and 28 days post-infection to evaluate different tests required. Whole blood was collected with heparin or ethylenediamine tetra-acetic acid as anticoagulant to help in the hematological studies such as red blood cells count (RBCs), white blood cells count, packed cell volume (PCV), and hemoglobin (Hb). Only marked increase in the total leuckocytic count was recorded while RBCs, PCV, and Hb were decreased in most of the results obtained. Total protein and globulin decreased while albumin and A/G ratio increased. Liver enzymes showing marked increase in aspartate aminotransferase and increase in alanine aminotransferase in dogs and rats denoting that liver has a role in the response to that infection. Kidney-function tests, urea, and creatinine showed slight increase at 6 days post-infection (d.p.i.). After preparation of different Ag (antigen) from different collected helminthes, the protein content of each was determined. The sera of infected animals were collected to find antibodies in their blood against the parasite using enzyme-linked immunosorbent assay and using crude heterophyid antigen collected from their intestines after scarification. The worms washed, homogenized, and then centrifuged to collect supernatant fluid as antigens. The results indicated that antibody starts to appear at 9 d.p.i. and increases till 21 and 28 d.p.i. and detection depends on antigen concentration.

Intestinal Parasitic Infections in Human Immunodeficiency Virus-Infected and Noninfected Persons in a High Human Immunodeficiency Virus Prevalence Region of Cameroon.

PubMed

Nkenfou, Céline Nguefeu; Tchameni, Sandrine Mboula; Nkenfou, Carine Nguefeu; Djataou, Patrice; Simo, Ulrich Florian; Nkoum, Alexandre Benjamin; Estrin, William

2017-09-01

The problem of intestinal parasitic infection in human immunodeficiency virus (HIV)-infected people requires careful consideration in the developing world where poor nutrition is associated with poor hygiene and several coinfecting diseases. Studies have addressed this issue in Cameroon, especially in the low HIV prevalence area. The current study was conducted to determine the prevalence of intestinal parasitosis in people living with HIV (PLHIV) in Adamaoua and to identify associated risk factors. Stool and blood specimens from study participants were screened for intestinal parasites and anti-HIV antibodies, respectively. Of 235 participants, 68 (28.9%) were HIV positive, 38 of them on antiretroviral treatment (ART). The overall prevalence of intestinal parasites was 32.3%. Of 68 PLHIV, 32.3% (22/68) were infected with intestinal parasites, compared with 32.3% (54/167) of the HIV-negative patients. Univariate analysis showed no difference between the prevalence of intestinal parasites among PLHIV and HIV-negative patients ( P = 0.69). ART was not associated with the prevalence of intestinal parasites. Multivariate analysis showed that the quality of water and the personal hygiene were the major risk factors associated to intestinal parasitosis. The level of education was associated with HIV serostatus: the higher the level of education, the lower the risk of being infected with HIV ( P = 0.00). PLHIV and the general population should be screened routinely for intestinal parasites and treated if infected.

Diagnosis of Plasmodium falciparum infection in man: detection of parasite antigens by ELISA*

PubMed Central

Mackey, L. J.; McGregor, I. A.; Paounova, N.; Lambert, P. H.

1982-01-01

An ELISA method has been developed for the diagnosis of Plasmodium falciparum infection in man. Parasites from in vitro cultures of P. falciparum were used as source of antigen for the solid phase and the source of specific antibody was immune Gambian sera; binding of antibody in antigen-coated wells was registered by means of alkaline phosphatase-conjugated anti-human IgG. Parasites were detected on the basis of inhibition of antibody-binding. The test was applied to the detection of parasites in human red blood cells (RBC) from in vitro cultures of P. falciparum and in RBC from infected Gambians; RBC from 100 Geneva blood donors served as normal, uninfected controls. In titration experiments, the degree of antibody-binding inhibition correlated with the number of parasites in the test RBC. Parasites were detected at a level of 8 parasites/106 RBC. Samples of RBC were tested from 126 Gambians with microscopically proven infection; significant antibody-binding inhibition was found in 86% of these cases, where parasitaemia ranged from 10 to 125 000/μl of blood. The presence of high-titre antibody in the test preparations was found to reduce the sensitivity of parasite detection in infected RBC from in vitro cultures mixed with equal volumes of different antibody-containing sera. The sensitivity was restored in most cases by recovering the RBC by centrifugation before testing. In a preliminary experiment, there was no significant difference in antibody-binding inhibition using fresh infected RBC and RBC dried on filter-paper and recovered by elution, although there was greater variation in the latter samples. PMID:7044589

Parasite infections in nestling red-shouldered hawks (Buteo lineatus) in northeast Wisconsin.

PubMed

King, Janet C; Dubay, Shelli A; Huspeni, Todd C; VanLanen, Andrew R; Gerhold, Richard W

2010-06-01

Red-shouldered hawks (Buteo lineatus) are threatened in Wisconsin and long-term data suggest that nest productivity is low in the state for unknown reasons. Our objective was to determine whether red-shouldered hawks in northeast Wisconsin were infected with parasites that could contribute to low nest productivity. We examined nestlings for the presence of Trichomonas gallinae, Protocalliphora avium, and blood parasites in June 2006 and 2007. We did not detect T. gallinae in throat swabs taken from 24 nestlings in 2007. Ear canals of nestlings were parasitized by P. avium larvae in 10 of 11 (91%) nests and in 22 of 24 (92%) nestlings. Larvae were found in higher intensity in 1 ear relative to the other. Leucocytozoon toddi was present in 90.5% (38/42) of the nestlings. At least 1 bird in each nest was infected. Intensity of L. toddi averaged 48.6 +/- 58.3 infected cells per 2,000 erythrocytes (2.4 +/- 2.9%). No other blood parasites were identified.

[Survey of infections of intestinal parasites and related factors in north-west Shandong Province].

PubMed

Xu, Yan; Miao, Feng; Kong, Xiang-Li; Wang, Yong-Bin; Bu, Xiu-Qin; Zhang, Ben-Guang; Zhao, Chang-Lei; Liu, Xin; Chen, Xi-Xin

2014-10-01

To understand the infection status of intestinal parasites and related knowledge and behavior factors of the residents in north-west Shandong Province, so as to provide the evidence for taking targeted preventive measures. Eighteen villages were randomly selected as survey spots by the stratified multi-stage sample method. The Kato-Katz technique was used to detect intestinal parasite eggs among the residents and the cellophane tape anus test was used to detect Enterobius vermicularis eggs among 3-12 years old children. Questionnaires were applied to investigate related knowledge and behavior factors about the intestinal parasite infections in the residents. Totally 6 366 residents were detected for intestinal parasites and the infection rate was 0.28% (18 cases). Totally 895 children were detected for E. vermicularis and the infection rate was 5.70% (51 cases). Totally 2 915 residents were investigated by questionnaires and the awareness rate of knowledge about preventing parasitic diseases was 26.72%. The formation rates of washing hands before meal and after WC, washing fruit and vegetable before eating, never drinking unboiled water were 55.42%, 42.87%, 43.54% and 83.04% respectively. The awareness rate of knowledge about preventing parasitic diseases of 3-12 years old children was 12.24%; and the formation rates of washing hands before meal and after WC were 47.04% and 30.44% respectively. The total infection rate of intestinal parasites is low but the E. vermicularis infection rate is high among children in north-west Shandong Province. The awareness rate of knowledge about preventing parasitic diseases and the formation rates of healthy behaviors are all low. Therefore, the targeted health education should be taken to increase the awareness rate and guide the residents to develop their healthy behaviors.

A novel association of acquired ADAMTS13 inhibitor and acute dengue virus infection

PubMed Central

Rossi, Fernanda C.; Angerami, Rodrigo N.; de Paula, Erich V.; Orsi, Fernanda L.; Shang, Dezhi; del Guercio, Vânia M.; Resende, Mariângela R.; Annichino-Bizzacchi, Joyce M.; da Silva, Luiz J.; Zheng, X. Long; Castro, Vagner

2011-01-01

BACKGROUND Dengue is a mosquito-borne viral disease with an increasing incidence worldwide. Thrombocytopenia is a common finding in dengue virus (DV) infection; however, the underlying mechanisms remain unknown. CASE REPORT Here we provide the first evidence of a case of antibody formation against ADAMTS13 (ADAMTS13 inhibitor) in the course of a severe acute DV infection resulting in thrombotic microangiopathy (TMA). The patient presented with classical dengue symptoms (positive epidemiology, high fever, myalgia, predominantly in the lower limbs and lumbar region for 1 week) and, after 11 days of initial symptoms, developed TMA. Clinical and laboratorial investigation of dengue and TMA was performed. RESULTS The patient presented with ADAMTS13 inhibitor (IgG) during the acute phase of the disease, without anti-platelet antibodies detectable. Dengue infection had laboratorial confirmation. There were excellent clinical and laboratory responses to 11 serial plasma exchanges. Anti-ADAMTS13 inhibitor disappeared after remission of TMA and dengue resolution. No recurrence of TMA symptoms was observed after 2-year follow-up. CONCLUSIONS Although the real incidence of dengue-related TMA is unknown, this case provides the basis for future epidemiologic studies on acquired ADAMTS13 deficiency in DV infection. The prompt clinical recognition of this complication and early installment of specific therapy with plasma exchange are likely to improve the outcome of severe cases of dengue. PMID:19788513

A novel association of acquired ADAMTS13 inhibitor and acute dengue virus infection.

PubMed

Rossi, Fernanda C; Angerami, Rodrigo N; de Paula, Erich V; Orsi, Fernanda L; Shang, Dezhi; del Guercio, Vânia M; Resende, Mariângela R; Annichino-Bizzacchi, Joyce M; da Silva, Luiz J; Zheng, X Long; Castro, Vagner

2010-01-01

Dengue is a mosquito-borne viral disease with an increasing incidence worldwide. Thrombocytopenia is a common finding in dengue virus (DV) infection; however, the underlying mechanisms remain unknown. Here we provide the first evidence of a case of antibody formation against ADAMTS13 (ADAMTS13 inhibitor) in the course of a severe acute DV infection resulting in thrombotic microangiopathy (TMA). The patient presented with classical dengue symptoms (positive epidemiology, high fever, myalgia, predominantly in the lower limbs and lumbar region for 1 week) and, after 11 days of initial symptoms, developed TMA. Clinical and laboratorial investigation of dengue and TMA was performed. The patient presented with ADAMTS13 inhibitor (IgG) during the acute phase of the disease, without anti-platelet antibodies detectable. Dengue infection had laboratorial confirmation. There were excellent clinical and laboratory responses to 11 serial plasma exchanges. Anti-ADAMTS13 inhibitor disappeared after remission of TMA and dengue resolution. No recurrence of TMA symptoms was observed after 2-year follow-up. Although the real incidence of dengue-related TMA is unknown, this case provides the basis for future epidemiologic studies on acquired ADAMTS13 deficiency in DV infection. The prompt clinical recognition of this complication and early installment of specific therapy with plasma exchange are likely to improve the outcome of severe cases of dengue.

Molecular appraisal of intestinal parasitic infection in transplant recipients

PubMed Central

Yadav, Pooja; Khalil, Shehla; Mirdha, Bijay Ranjan

2016-01-01

Background & objectives: Diarrhoea is the main clinical manifestation caused by intestinal parasitic infections in patients, with special reference to transplant recipients who require careful consideration to reduce morbidity and mortality. Further, molecular characterization of some important parasites is necessary to delineate the different modes of transmission to consider appropriate management strategies. We undertook this study to investigate the intestinal parasitic infections in transplant recipients with or without diarrhoea, and the genotypes of the isolated parasites were also determined. Methods: Stool samples from 38 transplant recipients comprising 29 post-renal, two liver and seven bone marrow transplant (BMT) recipients presenting with diarrhoea and 50 transplant recipients (42 post-renal transplant, eight BMT) without diarrhoea were examined for the presence of intestinal parasites by light microscopy using wet mount, modified Ziehl–Neelsen staining for intestinal coccidia and modified trichrome staining for microsporidia. Genotypes of Cryptosporidium species were determined by multilocus genotyping using small subunit ribosomal (SSUrRNA), Cryptosporidium oocyst wall protein (COWP) and dihydrofolate reductase (DHFR) as the target genes. Assemblage study for Giardia lamblia was performed using triose phosphate isomerase (TPI) as the target gene. Samples were also screened for bacterial, fungal and viral pathogens. Results: The parasites that were detected included Cryptosporidium species (21%, 8/38), Cystoisospora (Isospora) belli (8%, 3), Cyclospora cayetanensis (5%, 2), G. lamblia (11%, 4), Hymenolepis nana (11%, 4), Strongyloides stercoralis (3%, 1) and Blastocystis hominis (3%, 1). Multilocus genotyping of Cryptosporidium species at SSUrRNA, COWP and DHFR loci could detect four isolates of C. hominis; two of C. parvum, one of mixed genotype and one could not be genotyped. All the C. hominis isolates were detected in adult post

Humanized Mouse Models for the Study of Human Malaria Parasite Biology, Pathogenesis, and Immunity.

PubMed

Minkah, Nana K; Schafer, Carola; Kappe, Stefan H I

2018-01-01

Malaria parasite infection continues to inflict extensive morbidity and mortality in resource-poor countries. The insufficiently understood parasite biology, continuously evolving drug resistance and the lack of an effective vaccine necessitate intensive research on human malaria parasites that can inform the development of new intervention tools. Humanized mouse models have been greatly improved over the last decade and enable the direct study of human malaria parasites in vivo in the laboratory. Nevertheless, no small animal model developed so far is capable of maintaining the complete life cycle of Plasmodium parasites that infect humans. The ultimate goal is to develop humanized mouse systems in which a Plasmodium infection closely reproduces all stages of a parasite infection in humans, including pre-erythrocytic infection, blood stage infection and its associated pathology, transmission as well as the human immune response to infection. Here, we discuss current humanized mouse models and the future directions that should be taken to develop next-generation models for human malaria parasite research.

Prevalence of intestinal parasitic infections among highland and lowland dwellers in Gamo area, South Ethiopia.

PubMed

Wegayehu, Teklu; Tsalla, Tsegaye; Seifu, Belete; Teklu, Takele

2013-02-18

Epidemiological information on the prevalence of intestinal parasitic infections in different regions is a prerequisite to develop appropriate control strategies. Therefore, this present study was conducted to assess the magnitude and pattern of intestinal parasitism in highland and lowland dwellers in Gamo area, South Ethiopia. Community-based cross-sectional study was conducted between September 2010 and July 2011 at Lante, Kolla Shelle, Dorze and Geressie kebeles of Gamo Gofa Zone, South Ethiopia. The study sites and study participants were selected using multistage sampling method. Data were gathered through house-to-house survey. A total of 858 stool specimens were collected and processed using direct wet mount and formol-ether concentration techniques for the presence of parasite. Out of the total examined subjects, 342(39.9%) were found positive for at least one intestinal parasite. The prevalence of Entamoeba histolytica/dispar was the highest 98(11.4%), followed by Giardia lamblia 91(10.6%), Ascaris lumbricoides 67(7.8%), Strongyloides stercoralis 51(5.9%), hookworm 42(4.9%), Trichuris trichiura 24(2.8%), Taenia species 18(2.1%), Hymenolepis nana 7(0.6%) and Schistosoma mansoni 1(0.12%). No statistically significant difference was observed in the prevalence of intestinal parasitic infections among lowland (37.9%) and highland dwellers (42.3%) (P = 0.185). The prevalence of intestinal parasitic infection was not significantly different among the study sites but it was relatively higher in Geressie (42.8%) than other kebeles. Sex was not associated with parasitic infections (P = 0.481). No statistically significant difference of infection was observed among the age groups (P = 0.228) but it was higher in reproductive age group. The high prevalence of intestinal parasitic infections among the lowland and highland dwellers in Gamo area indicated that parasitic infections are important public health problems. Thus, infection control measures and the

Zoonotic intestinal parasites of carnivores: A systematic review in Iran

PubMed Central

Sarvi, Shahabeddin; Daryani, Ahmad; Sharif, Mehdi; Rahimi, Mohammad Taghi; Kohansal, Mohammad Hasan; Mirshafiee, Siavash; Siyadatpanah, Abolghasem; Hosseini, Seyed-Abdollah; Gholami, Shirzad

2018-01-01

Aim: Parasitic infections, especially of the zoonotic-parasitic type, are the most important health, economic, and social problems in developing countries, including Iran. The aim of this study was to review systematically the available data on gastrointestinal parasites of carnivores in Iran and their ability to infect humans. Materials and Methods: Studies reporting intestinal parasites of carnivores were systematically collected from nine electronic English and Persian databases and Proceedings of Iranian parasitology and veterinary congresses published between 1997 and 2015. A total of 26 studies issued from 1997 to 2015 met the eligibility criteria. Results: The pooled proportion of intestinal parasites of carnivores was estimated as 80.4% (95% confidence interval=70.2-88.8%). The overall prevalence of gastrointestinal parasites in dogs, cats, foxes, and jackals were 57.89%, 90.62%, 89.17%, and 97.32%, respectively. Dipylidium caninum (20.45%), Toxocara spp. (18.81%), Taenia hydatigena (15.28%), Mesocestoides lineatus (11.83%), Echinococcus granulosus (10%), and Toxascaris leonina (8.69%) were the most frequently observed parasites. Conclusion: High prevalence rates of zoonotic intestinal parasites of carnivores particularly Echinococcus spp. and Toxocara spp. increase the risk of acquiring zoonotic infections such as cystic hydatid, alveolar cysts, and visceral or ocular larva migrants in Iranian people. Therefore, it is essential for public health centers to develop more effective control strategies to decrease infections rates in carnivores’ populations. PMID:29479158

Parasitic infections and maternal anaemia among expectant mothers in the Dangme East District of Ghana.

PubMed

Tay, Samuel Crowther Kofi; Nani, Emmanuel Agbeko; Walana, Williams

2017-01-03

Parasitic infections are of public health concern globally, particular among at risk groups such as pregnant women in developing countries. The presence of these parasites during pregnancy potentiate adverse effects to both the mother and the unborn baby. This study sought to establish the prevalence of some parasitic agents among antenatal attendees in the Dangme East District of Ghana. A cross-sectional prospective study was conduct between April and July, 2012. Venous blood specimens were collected from each participant for haemoglobin estimation and malaria microscopy. In addition participants' early morning mid-stream urine and stool specimens were analyzed microscopically for parasitic agents. A total of 375 pregnant women were involved in the study, of which anaemia was present in 66.4% (249/375). However, parasitic infections associated anaemia prevalence was 49.6% (186/375). In all, 186 cases of parasitic infections were observed; 171 (44.0%) were single isolated infections while 15 (4.0%) were co-infections. Plasmodium species were significantly associated with anaemia (13.3%, χ 2  = 23.290, p < 0.001). Also, the presence of Schistosoma haematobium (3.7%, χ 2  = 7.267, p = 0.008), Schistosoma mansoni (5.3%, χ 2  = 5.414, p = 0.023) and hookworm (3.7%, χ 2  = 11.267, p = 0.008) were significantly associated with anaemia in pregnancy. Except where co-infections exist (3.7%, χ 2  = 11.267, p = 0.001), the rest of the single infections were insignificantly associated with anaemia. Collectively, intestinal helminthes were predominantly significant with anaemia in pregnancy (p = 0.001, χ 2  = 107.800). The study revealed relatively high prevalence of parasitic infections among the study population, suggesting that about three-quarters of the anaemic mothers are either single or co-infected with parasitic agents.

The expression of virulence during double infections by different parasites with conflicting host exploitation and transmission strategies.

PubMed

Ben-Ami, F; Rigaud, T; Ebert, D

2011-06-01

In many natural populations, hosts are found to be infected by more than one parasite species. When these parasites have different host exploitation strategies and transmission modes, a conflict among them may arise. Such a conflict may reduce the success of both parasites, but could work to the benefit of the host. For example, the less-virulent parasite may protect the host against the more-virulent competitor. We examine this conflict using the waterflea Daphnia magna and two of its sympatric parasites: the blood-infecting bacterium Pasteuria ramosa that transmits horizontally and the intracellular microsporidium Octosporea bayeri that can concurrently transmit horizontally and vertically after infecting ovaries and fat tissues of the host. We quantified host and parasite fitness after exposing Daphnia to one or both parasites, both simultaneously and sequentially. Under conditions of strict horizontal transmission, Pasteuria competitively excluded Octosporea in both simultaneous and sequential double infections, regardless of the order of exposure. Host lifespan, host reproduction and parasite spore production in double infections resembled those of single infection by Pasteuria. When hosts became first vertically (transovarilly) infected with O. bayeri, Octosporea was able to withstand competition with P. ramosa to some degree, but both parasites produced less transmission stages than they did in single infections. At the same time, the host suffered from reduced fecundity and longevity. Our study demonstrates that even when competing parasite species utilize different host tissues to proliferate, double infections lead to the expression of higher virulence and ultimately may select for higher virulence. Furthermore, we found no evidence that the less-virulent and vertically transmitting O. bayeri protects its host against the highly virulent P. ramosa. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

Targeting channels and transporters in protozoan parasite infections

NASA Astrophysics Data System (ADS)

Meier, Anna; Erler, Holger; Beitz, Eric

2018-03-01

Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e. channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease) and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).

Infection Control and Prevention: A Review of Hospital-Acquired Infections and the Economic Implications

PubMed Central

Reed, Deoine; Kemmerly, Sandra A.

2009-01-01

The Centers for Disease Control and Prevention estimates that 2 million patients suffer from hospital-acquired infections every year and nearly 100,000 of them die. Most of these medical errors are preventable. Hospital-acquired infections result in up to $4.5 billion in additional healthcare expenses annually. The U.S. government has responded to this financial loss by focusing on healthcare quality report cards and by taking strong action to curb healthcare spending. The Medicare Program has proposed changes to the Hospital Inpatient Prospective Payment System and Fiscal Year Rates: Proposed Rule CMS 1488-P-Healthcare-associated infection. Payment will be linked to performance. Under the new rule, payment will be withheld from hospitals for care associated with treating certain catheter-associated urinary tract infections, vascular catheter-associated infections, and mediastinitis after coronary artery bypass graft surgery. Infection-prevention strategies are essential. In the healthcare setting, the infection control department is categorized as non-revenue-producing. Funds dedicated to resources such as staff, educational programs, and prevention measures are vastly limited. Hospital leaders will need to balance the upfront cost needed to prevent hospital-related infections with the non-reimbursed expense accrued secondary to potentially preventable infections. The purpose of this paper is to present case studies and cost analysis of hospital-acquired infections and present strategies that reduce infections and cost. PMID:21603406

Virulence evolution in response to anti-infection resistance: toxic food plants can select for virulent parasites of monarch butterflies.

PubMed

de Roode, J C; de Castillejo, C Lopez Fernandez; Faits, T; Alizon, S

2011-04-01

Host resistance to parasites can come in two main forms: hosts may either reduce the probability of parasite infection (anti-infection resistance) or reduce parasite growth after infection has occurred (anti-growth resistance). Both resistance mechanisms are often imperfect, meaning that they do not fully prevent or clear infections. Theoretical work has suggested that imperfect anti-growth resistance can select for higher parasite virulence by favouring faster-growing and more virulent parasites that overcome this resistance. In contrast, imperfect anti-infection resistance is thought not to select for increased parasite virulence, because it is assumed that it reduces the number of hosts that become infected, but not the fitness of parasites in successfully infected hosts. Here, we develop a theoretical model to show that anti-infection resistance can in fact select for higher virulence when such resistance reduces the effective parasite dose that enters a host. Our model is based on a monarch butterfly-parasite system in which larval food plants confer resistance to the monarch host. We carried out an experiment and showed that this environmental resistance is most likely a form of anti-infection resistance, through which toxic food plants reduce the effective dose of parasites that initiates an infection. We used these results to build a mathematical model to investigate the evolutionary consequences of food plant-induced resistance. Our model shows that when the effective infectious dose is reduced, parasites can compensate by evolving a higher per-parasite growth rate, and consequently a higher intrinsic virulence. Our results are relevant to many insect host-parasite systems, in which larval food plants often confer imperfect anti-infection resistance. Our results also suggest that - for parasites where the infectious dose affects the within-host dynamics - vaccines that reduce the effective infectious dose can select for increased parasite virulence. �

Parasitism, personality and cognition in fish.

PubMed

Barber, I; Mora, A B; Payne, E M; Weinersmith, K L; Sih, A

2017-08-01

It is well established that parasites can have profound effects on the behaviour of host organisms, and that individual differences in behaviour can influence susceptibility to parasite infections. Recently, two major themes of research have developed. First, there has been a growing interest in the proximate, mechanistic processes underpinning parasite-associated behaviour change, and the interactive roles of the neuro-, immune, and other physiological systems in determining relationships between behaviour and infection susceptibility. Secondly, as the study of behaviour has shifted away from one-off measurements of single behaviours and towards a behavioural syndromes/personality framework, research is starting to focus on the consequences of parasite infection for temporal and contextual consistency of behaviour, and on the implications of different personality types for infection susceptibility. In addition, there is increasing interest in the potential for relationships between cognition and personality to also have implications for host-parasite interactions. As models well-suited to both the laboratory study of behaviour and experimental parasitology, teleost fish have been used as hosts in many of these studies. In this review we provide a broad overview of the range of mechanisms that potentially generate links between fish behaviour, personality, and parasitism, and illustrate these using examples drawn from the recent literature. In addition, we examine the potential interactions between cognition, personality and parasitism, and identify questions that may be usefully investigated with fish models. Copyright © 2016 Elsevier B.V. All rights reserved.

Parasite prevalence, infection intensity and richness in an endangered population, the Atlantic-Gaspésie caribou.

PubMed

Turgeon, Geneviève; Kutz, Susan J; Lejeune, Manigandan; St-Laurent, Martin-Hugues; Pelletier, Fanie

2018-04-01

The Atlantic-Gaspésie caribou ( Rangifer tarandus caribou ) population is a small isolated relict herd considered endangered according to the Canadian Species at Risk Act (SARA). This population has low recruitment and survival rates but the potential role of parasites on individual fitness is unknown. In this context, we explored the parasite status of this population with the aim of 1) assessing the occurrence and intensity of parasite infections and the spatial, temporal and individual variations, 2) quantifying parasite richness and investigating factors such as sex and host body condition that may be associated with this variable and 3) evaluating the effects of parasite infections on survival in the Atlantic-Gaspésie caribou population. We examined fecal samples from 32 animals captured in 2013-2014 for eggs, oocysts and larvae of parasites and detected 7 parasite species: dorsal-spined larvae protostrongylids, presumably Parelaphostrongylus andersoni based on PCR identification of a subset, Nematodirus odocoilei and other unidentified Strongyles, Trichuris sp., Capillaria sp., Moniezia sp. and Eimeria sp. For each caribou, mean parasite species richness was 1.8 ± 1.1 (SD). Sex, body condition, year and capture location did not explain parasite prevalence, intensity of infection or richness except for intensity of infection of Capillaria sp. that was positively influenced by body condition. Parasites did not influence survival although mortality was higher for males than for females. We suggest that the relatively low and common gastrointestinal and protostrongylid parasite infections will not be a short-term threat leading to extinction.

Resource competition between two fungal parasites in subterranean termites

NASA Astrophysics Data System (ADS)

Chouvenc, Thomas; Efstathion, Caroline A.; Elliott, Monica L.; Su, Nan-Yao

2012-11-01

Subterranean termites live in large groups in underground nests where the pathogenic pressure of the soil environment has led to the evolution of a complex interaction among individual and social immune mechanisms in the colonies. However, groups of termites under stress can show increased susceptibility to opportunistic parasites. In this study, an isolate of Aspergillus nomius Kurtzman, Horn & Hessltine was obtained from a collapsed termite laboratory colony. We determined that it was primarily a saprophyte and, secondarily, a facultative parasite if the termite immunity is undergoing a form of stress. This was determined by stressing individuals of the Formosan subterranean termite Coptotermes formosanus Shiraki via a co-exposure to the virulent fungal parasite Metarhizium anisopliae (Metch.) Sorokin. We also examined the dynamics of a mixed infection of A. nomius and M. anisopliae in a single termite host. The virulent parasite M. anisopliae debilitated the termite immune system, but the facultative, fast growing parasite A. nomius dominated the mixed infection process. The resource utilization strategy of A. nomius during the infection resulted in successful conidia production, while the chance for M. anisopliae to complete its life cycle was reduced. Our results also suggest that the occurrence of opportunistic parasites such as A. nomius in collapsing termite laboratory colonies is the consequence of a previous stress, not the cause of the stress.

Analysis of a summary network of co-infection in humans reveals that parasites interact most via shared resources

PubMed Central

Griffiths, Emily C.; Pedersen, Amy B.; Fenton, Andy; Petchey, Owen L.

2014-01-01

Simultaneous infection by multiple parasite species (viruses, bacteria, helminths, protozoa or fungi) is commonplace. Most reports show co-infected humans to have worse health than those with single infections. However, we have little understanding of how co-infecting parasites interact within human hosts. We used data from over 300 published studies to construct a network that offers the first broad indications of how groups of co-infecting parasites tend to interact. The network had three levels comprising parasites, the resources they consume and the immune responses they elicit, connected by potential, observed and experimentally proved links. Pairs of parasite species had most potential to interact indirectly through shared resources, rather than through immune responses or other parasites. In addition, the network comprised 10 tightly knit groups, eight of which were associated with particular body parts, and seven of which were dominated by parasite–resource links. Reported co-infection in humans is therefore structured by physical location within the body, with bottom-up, resource-mediated processes most often influencing how, where and which co-infecting parasites interact. The many indirect interactions show how treating an infection could affect other infections in co-infected patients, but the compartmentalized structure of the network will limit how far these indirect effects are likely to spread. PMID:24619434

The interrelation between intestinal parasites and latent TB infections among newly resettled refugees in Texas.

PubMed

Board, Amy R; Suzuki, Sumihiro

2016-01-01

Previous research has documented that parasite infection may increase vulnerability to TB among certain at risk populations. The purpose of this study was to identify whether an association exists between latent tuberculosis infection (LTBI) and intestinal parasite infection among newly resettled refugees in Texas while controlling for additional effects of region of origin, age and sex. Data for all refugees screened for both TB and intestinal parasites between January 2010 and mid-October 2013 were obtained from the Texas Refugee Health Screening Program and were analyzed using logistic regression. A total of 9860 refugees were included. In multivariable logistic regression analysis, pathogenic and non-pathogenic intestinal parasite infections yielded statistically significant reduced odds of LTBI. However, when individual parasite species were analyzed, hookworm infection indicated statistically significant increased odds of LTBI (OR 1.674, CI: 1.126-2.488). A positive association exists between hookworm infection and LTBI in newly arrived refugees to Texas. More research is needed to assess the nature and extent of these associations. © The Author 2015. 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.

Clinical role of Cefixime in community-acquired infections.

PubMed

Dreshaj, Sh; Doda-Ejupi, T; Tolaj, I Q; Mustafa, A; Kabashi, S; Shala, N; Geca, Nj; Aliu, A; Daka, A; Basha, N

2011-01-01

Cefixime is an oral third generation cephalosporin, frequently used in respiratory tract infections (RTI) in the pediatric population. However, in some publications cefixime has demonstrated poor efficacy against staphylococci and streptococci. of this study was to evaluate the efficacy of cefixime in the treatment of community-acquired infections in a country where parenteral third generation cephalosporins have been used for a long time. The present study was designed to assess the clinical efficacy, bacteriological eradication rates and tolerability of cefixime in children with community-acquired upper RTI (URTI), lower RTI (LRTI) and uncomplicated urinary tract infections (UTI). The study was prospective, open, and included 89 patients, from 6 months to 28 years, of both sexes, with the diagnosis of community-acquired URTI, LRTI and UTI. The treatment with cefixime was successful in 30/30 (100%) patients suffering from acute otitis media (AOM), in 10/12 (83.3%) with acute sinusitis, in 12/12 patients (100%) with pneumonia, in 31/35 (88.57) with uncomplicated UTI. The antibiotic was well tolerated. In 10 days treatment we recorded one case (1.3%) with acute gastroenteritis and two cases (2.6%) of maculopapular rash. Side-effects were transient and disappeared after finishing therapy in all three of the cases. Community-acquired infections, such as AOM, LRTI and UTI, caused by susceptible pathogens, can be treated with cefixime, as a good choice for a successful clinical response.

A DTU-dependent blood parasitism and a DTU-independent tissue parasitism during mixed infection of Trypanosoma cruzi in immunosuppressed mice.

PubMed

Sales-Campos, Helioswilton; Kappel, Henrique Borges; Andrade, Cristiane Pontes; Lima, Tiago Pereira; Mattos, Mardén Estevão; de Castilho, Alessandra; Correia, Dalmo; Giraldo, Luis Eduardo Ramirez; Lages-Silva, Eliane

2014-01-01

Trypanosoma cruzi (Tc) diversity is determined by different biological, genetic, and biochemical markers and has been grouped into six discrete typing units (DTUs) or taxonomic groups (TcI-TcVI). This variability, coupled with natural reinfection or the hosts' immunosuppression, may play an important role in the pathogenesis of Chagas disease. Therefore, we evaluated the blood and tissue parasitism and genetic profile of mice coinfected with the TcII (JG) strain and TcI AQ1-7 (AQ) or MUTUM (MT) strains during the acute and chronic phases of the disease and during immunosuppression. T. cruzi blood populations in mixed infections were clearly associated with the TcII strain during acute and chronic phases or during immunosuppression. However, in tissues, the parasite populations were distributed according to the strain and the stage of infection. TcII populations overlapped TcI strains during the acute phase; in contrast, during chronic phase, both TcI strains were more prevalent than the TcII strain. The immunosuppression induced selective exacerbation of parasite populations, leading to reactivation of the TcII strain when associated with the AQ, but not with MT strain. Thus, a differential distribution of T. cruzi populations in blood and tissues with overlapping according to the stage of infection and strain used was observed. Blood parasitism was associated with the DTU TcII and tissue parasitism with a specific parasite strain and not with DTUs. Finally, to our knowledge, this is the first study to analyze subpatent blood parasitism and to simultaneously identify different T. cruzi populations in tissues and blood.

[Inequality in the prevalence of intestinal parasitic infections among schoolchildren from urban and rural schools].

PubMed

Barra, Marco; Bustos, Luis; Ossa, Ximena

2016-07-01

Parasitic infections in children reflect social inequalities throughout the world, especially in urban and rural territories. To assess inequalities in the prevalence of infections by protozoa and intestinal helminths and associated factors in children of different geographical areas from the commune of Puerto Montt. Cross-sectional study carried out in 103 students from one urban and two rural schools in the commune of Puerto Montt. A socio-demographic survey was applied and the presence parasitic infections was evaluated in serial stool samples. The prevalence of Protozoan and intestinal helminthic infections were 37.5 and 68.1% in urban and rural areas respectively. A regression analysis showed that the differences between rural and urban children, disappear when the results are adjusted by family income and the quality of sewage disposal. In urban children, the prevalence of parasitic infections increases along with the decrease in family income. Income and sanitary conditions rather than being or urban or rural origin explain the variations in rates of childhood parasitic infections. Infections with protozoa and intestinal helminths are an indicator of social inequality in health.

PfCDPK1 is critical for malaria parasite gametogenesis and mosquito infection

PubMed Central

Bansal, Abhisheka; Molina-Cruz, Alvaro; Brzostowski, Joseph; Liu, Poching; Luo, Yan; Gunalan, Karthigayan; Li, Yuesheng; Ribeiro, José M. C.; Miller, Louis H.

2018-01-01

Efforts to knock out Plasmodium falciparum calcium-dependent protein kinase 1 (PfCDPK1) from asexual erythrocytic stage have not been successful, indicating an indispensable role of the enzyme in asexual growth. We recently reported generation of a transgenic parasite with mutant CDPK1 [Bansal A, et al. (2016) MBio 7:e02011-16]. The mutant CDPK1 (T145M) had reduced activity of transphosphorylation. We reasoned that CDPK1 could be disrupted in the mutant parasites. Consistent with this assumption, CDPK1 was successfully disrupted in the mutant parasites using CRISPR/Cas9. We and others could not disrupt PfCDPK1 in the WT parasites. The CDPK1 KO parasites show a slow growth rate compared with the WT and the CDPK1 T145M parasites. Additionally, the CDPK1 KO parasites show a defect in both male and female gametogenesis and could not establish an infection in mosquitoes. Complementation of the KO parasite with full-length PfCDPK1 partially rescued the asexual growth defect and mosquito infection. Comparative global transcriptomics of WT and the CDPK1 KO schizonts using RNA-seq show significantly high transcript expression of gametocyte-specific genes in the CDPK1 KO parasites. This study conclusively demonstrates that CDPK1 is a good target for developing transmission-blocking drugs. PMID:29311293

PfCDPK1 is critical for malaria parasite gametogenesis and mosquito infection.

PubMed

Bansal, Abhisheka; Molina-Cruz, Alvaro; Brzostowski, Joseph; Liu, Poching; Luo, Yan; Gunalan, Karthigayan; Li, Yuesheng; Ribeiro, José M C; Miller, Louis H

2018-01-23

Efforts to knock out Plasmodium falciparum calcium-dependent protein kinase 1 ( Pf CDPK1) from asexual erythrocytic stage have not been successful, indicating an indispensable role of the enzyme in asexual growth. We recently reported generation of a transgenic parasite with mutant CDPK1 [Bansal A, et al. (2016) MBio 7:e02011-16]. The mutant CDPK1 (T145M) had reduced activity of transphosphorylation. We reasoned that CDPK1 could be disrupted in the mutant parasites. Consistent with this assumption, CDPK1 was successfully disrupted in the mutant parasites using CRISPR/Cas9. We and others could not disrupt Pf CDPK1 in the WT parasites. The CDPK1 KO parasites show a slow growth rate compared with the WT and the CDPK1 T145M parasites. Additionally, the CDPK1 KO parasites show a defect in both male and female gametogenesis and could not establish an infection in mosquitoes. Complementation of the KO parasite with full-length Pf CDPK1 partially rescued the asexual growth defect and mosquito infection. Comparative global transcriptomics of WT and the CDPK1 KO schizonts using RNA-seq show significantly high transcript expression of gametocyte-specific genes in the CDPK1 KO parasites. This study conclusively demonstrates that CDPK1 is a good target for developing transmission-blocking drugs. Copyright © 2018 the Author(s). Published by PNAS.

Experimental parasite community ecology: intraspecific variation in a large tapeworm affects community assembly.

PubMed

Benesh, Daniel P; Kalbe, Martin

2016-07-01

Non-random species associations occur in naturally sampled parasite communities. The processes resulting in predictable community structure (e.g. particular host behaviours, cross-immunity, interspecific competition) could be affected by traits that vary within a parasite species, like growth or antigenicity. We experimentally infected three-spined sticklebacks with a large tapeworm (Schistocephalus solidus) that impacts the energy needs, foraging behaviour and immune reactions of its host. The tapeworms came from two populations, characterized by high or low growth in sticklebacks. Our goal was to evaluate how this parasite, and variation in its growth, affects the acquisition of other parasites. Fish infected with S. solidus were placed into cages in a lake to expose them to the natural parasite community. We also performed a laboratory experiment in which infected fish were exposed to a fixed dose of a common trematode parasite. In the field experiment, infection with S. solidus affected the abundance of four parasite species, relative to controls. For two of the four species, changes occurred only in fish harbouring the high-growth S. solidus; one species increased in abundance and the other decreased. These changes did not appear to be directly linked to S. solidus growth though. The parasite exhibiting elevated abundance was the same trematode used in the laboratory infection. In that experiment, we found a similar infection pattern, suggesting that S. solidus affects the physiological susceptibility of fish to this trematode. Associations between S. solidus and other parasites occur and vary in direction. However, some of these associations were contingent on the S. solidus population, suggesting that intraspecific variability can affect the assembly of parasite communities. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

The bacterial parasite Pasteuria ramosa is not killed if it fails to infect: implications for coevolution.

PubMed

King, Kayla C; Auld, Stuart K J R; Wilson, Philip J; James, Janna; Little, Tom J

2013-02-01

Strong selection on parasites, as well as on hosts, is crucial for fueling coevolutionary dynamics. Selection will be especially strong if parasites that encounter resistant hosts are destroyed and diluted from the local environment. We tested whether spores of the bacterial parasite Pasteuria ramosa were passed through the gut (the route of infection) of their host, Daphnia magna, and whether passaged spores remained viable for a "second chance" at infecting a new host. In particular, we tested if this viability (estimated via infectivity) depended on host genotype, whether or not the genotype was susceptible, and on initial parasite dose. Our results show that Pasteuria spores generally remain viable after passage through both susceptible and resistant Daphnia. Furthermore, these spores remained infectious even after being frozen for several weeks. If parasites can get a second chance at infecting hosts in the wild, selection for infection success in the first instance will be reduced. This could also weaken reciprocal selection on hosts and slow the coevolutionary process.

Mini-FLOTAC, an innovative direct diagnostic technique for intestinal parasitic infections: experience from the field.

PubMed

Barda, Beatrice Divina; Rinaldi, Laura; Ianniello, Davide; Zepherine, Henry; Salvo, Fulvio; Sadutshang, Tsetan; Cringoli, Giuseppe; Clementi, Massimo; Albonico, Marco

2013-01-01

Soil-transmitted helminths and intestinal protozoa infection are widespread in developing countries, yet an accurate diagnosis is rarely performed. The aim of this study was to evaluate the recently developed mini-FLOTAC method and to compare with currently more widely used techniques for the diagnosis of intestinal parasitic infections in different settings. The study was carried out in Dharamsala, Himachal Pradesh, India, and in Bukumbi, Tanzania. A total of 180 pupils from two primary schools had their stool analyzed (n = 80 in Dharamsala and n = 100 in Bukumbi) for intestinal parasitic infections with three diagnostic methods: direct fecal smear, formol-ether concentration method (FECM) and mini-FLOTAC. Overall, 72% of the pupils were positive for any intestinal parasitic infection, 24% carried dual infections and 11% three infections or more. The most frequently encountered intestinal parasites were Entamoeba coli, Entamoeba histolytica/dispar, Giardia intestinalis, hookworm, (and Schistosoma mansoni, in Tanzania). Statistically significant differences were found in the detection of parasitic infections among the three methods: mini-FLOTAC was the most sensitive method for helminth infections (90% mini-FLOTAC, 60% FECM, and 30% direct fecal smear), whereas FECM was most sensitive for intestinal protozoa infections (88% FECM, 70% direct fecal smear, and 68% mini-FLOTAC). We present the first experiences with the mini-FLOTAC for the diagnosis of intestinal helminths and protozoa. Our results suggest that it is a valid, sensitive and potentially low-cost alternative technique that could be used in resource-limited settings--particularly for helminth diagnosis.

An investigation of parasitic infections and review of molecular characterization of the intestinal protozoa in nonhuman primates in China from 2009 to 2015.

PubMed

Li, Junqiang; Dong, Haiju; Wang, Rongjun; Yu, Fuchang; Wu, Yayun; Chang, Yankai; Wang, Chenrong; Qi, Meng; Zhang, Longxian

2017-04-01

Parasites are a well-known threat to nonhuman primate (NHP) populations, and potentially cause zoonotic diseases in humans. In this study, the basic data was provided of the parasites in NHPs and the molecular characterization of the Enterocytozoon bieneusi , Giardia duodenalis , Cryptosporidium spp., and Entamoeba spp. were reviewed, which were found in these samples. A total of 3349 fecal samples were collected from 34 species reared at 17 districts in zoos, farms, free-range, or research laboratories, and examined microscopically. Eleven genera of intestinal parasites were detected: five genera of protozoans ( Isospora spp., Entamoeba spp., Giardia sp., Cryptosporidium spp., and Cyclospora spp.) and six genera of helminths ( Trichuris spp., Strongyloides spp., Ascaris spp., Physaloptera spp., Ancylostoma spp., and Enterobius spp.). The overall sample prevalence of parasitic infection was 54.1% (1811/3349). Entamoeba spp. was the most prevalent (36.4%, 1218/3349). The infection rate was the highest in free-range animals (73.0%, 670/918) (P < 0.01) and Guangxi Zhuang autonomous region (64.8%, 566/873). Mixed infections were mostly detected for Entamoeba spp., Trichuris spp., and Strongyloides spp.. Molecular characterization was reviewed of Enterocytozoon bieneusi , Giardia duodenalis , Cryptosporidium spp., and Entamoeba spp., as these are zoonotic species or genotypes. This parasitological data for NHPs in China, provides important information for veterinarians and public health authorities for the elimination of such parasites and monitor the potential transmission of zoonotic infections from NHPs.

Increased Ca++ uptake by erythrocytes infected with malaria parasites: Evidence for exported proteins and novel inhibitors.

PubMed

Kushwaha, Ambuj K; Apolis, Liana; Ito, Daisuke; Desai, Sanjay A

2018-05-03

Malaria parasites export many proteins into their host erythrocytes and increase membrane permeability to diverse solutes. Although most solutes use a broad-selectivity channel known as the plasmodial surface anion channel, increased Ca ++ uptake is mediated by a distinct, poorly characterised mechanism that appears to be essential for the intracellular parasite. Here, we examined infected cell Ca ++ uptake with a kinetic fluorescence assay and the virulent human pathogen, Plasmodium falciparum. Cell surface labelling with N-hydroxysulfosuccinimide esters revealed differing effects on transport into infected and uninfected cells, indicating that Ca ++ uptake at the infected cell surface is mediated by new or altered proteins at the host membrane. Conditional knockdown of PTEX, a translocon for export of parasite proteins into the host cell, significantly reduced infected cell Ca ++ permeability, suggesting involvement of parasite-encoded proteins trafficked to the host membrane. A high-throughput chemical screen identified the first Ca ++ transport inhibitors active against Plasmodium-infected cells. These novel chemical scaffolds inhibit both uptake and parasite growth; improved in vitro potency at reduced free [Ca ++ ] is consistent with parasite killing specifically via action on one or more Ca ++ transporters. These inhibitors should provide mechanistic insights into malaria parasite Ca ++ transport and may be starting points for new antimalarial drugs. © 2018 John Wiley & Sons Ltd.

Intestinal parasitic infections in relation to HIV/AIDS status, diarrhea and CD4 T-cell count.

PubMed

Assefa, Shimelis; Erko, Berhanu; Medhin, Girmay; Assefa, Zelalem; Shimelis, Techalew

2009-09-18

HIV infection has been modifying both the epidemiology and outcome of parasitic infections. Hence, this study was undertaken to determine the prevalence of intestinal parasitic infection among people with and without HIV infection and its association with diarrhea and CD4 T-cell count. A cross-sectional study was conducted at Hawassa Teaching and Referral Hospital focusing on HIV positive individuals, who gave blood for CD4 T-cell count at their first enrollment and clients tested HIV negative from November, 2008 to March, 2009. Data on socio-demographic factors and diarrhea status were obtained by interviewing 378 consecutive participants (214 HIV positive and 164 HIV negative). Stool samples were collected from all study subjects and examined for parasites using direct, formol-ether and modified acid fast stain techniques. The prevalence of any intestinal parasitic infection was significantly higher among HIV positive participants. Specifically, rate of infection with Cryptosporidium, I. belli, and S. stercoralis were higher, particularly in those with CD4 count less than 200 cells/microL. Diarrhea was more frequent also at the same lower CD4 T-cell counts. Immunodeficiency increased the risk of having opportunistic parasites and diarrhea. Therefore; raising patient immune status and screening at least for those treatable parasites is important.

Cross-species infection trials reveal cryptic parasite varieties and a putative polymorphism shared among host species.

PubMed

Luijckx, Pepijn; Duneau, David; Andras, Jason P; Ebert, Dieter

2014-02-01

A parasite's host range can have important consequences for ecological and evolutionary processes but can be difficult to infer. Successful infection depends on the outcome of multiple steps and only some steps of the infection process may be critical in determining a parasites host range. To test this hypothesis, we investigated the host range of the bacterium Pasteuria ramosa, a Daphnia parasite, and determined the parasites success in different stages of the infection process. Multiple genotypes of Daphnia pulex, Daphnia longispina and Daphnia magna were tested with four Pasteuria genotypes using infection trials and an assay that determines the ability of the parasite to attach to the hosts esophagus. We find that attachment is not specific to host species but is specific to host genotype. This may suggest that alleles on the locus controlling attachment are shared among different host species that diverged 100 million year. However, in our trials, Pasteuria was never able to reproduce in nonnative host species, suggesting that Pasteuria infecting different host species are different varieties, each with a narrow host range. Our approach highlights the explanatory power of dissecting the steps of the infection process and resolves potentially conflicting reports on parasite host ranges. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

High prevalence of diarrhoegenic intestinal parasite infections among non-ART HIV patients in Fitche Hospital, Ethiopia.

PubMed

Adamu, Haileeyesus; Wegayehu, Teklu; Petros, Beyene

2013-01-01

HIV infection has been modifying both the epidemiology and outcome of parasite infections. Hence, this study was undertaken to determine the prevalence of Cryptosporidium and other intestinal parasite infections among HIV positives with and without Antiretroviral Treatment(ART) and its association with CD4+ T-cell count. A cross-sectional study was conducted at Fitche hospital focusing on HIV positives who came to hospital for follow-ups. A total of 378 HIV positive persons with and without ART participated in the study. Data on socio-demographic factors and diarrhoea status were obtained by interviewing all 214 with ART and 164 without ART. Stool samples were collected from all patients and examined for intestinal parasites using direct, formol-ether and modified acid-fast staining techniques. The prevalence of intestinal parasite infections in this study was significantly higher among HIV positive persons not on ART. Specifically, the rate of infection with Cryptosporidium species, Blastocystis spp., Giardia lamblia, and Entamoeba histolytica/E. dispar were higher, particularly in those with CD4+ T-cell counts less than 200 cells/µL. Fifty seven percent of the study participants were on ART. Out of these 164/378 (43%) of the non-ART study participants were infected with at least one intestinal parasite species. Significant association was observed between lower CD4+ T-cell count (<200 cells/µL) and the prevalence of Cryptosporidium spp. and Blastocystis spp. The two parasites were significantly more prevalent in HIV positive non-ART patients. HIV infection increased the risk of having Cryptosporidium and other intestinal parasites and diarrhoea. Therefore, raising HIV positive's immune status and screening for intestinal parasites is important. This study showed that patients who are taking ART had a lower prevalence of diarrhoea causing parasites and Cryptosporidium suggesting that ART through improvement of immune status of the patients may have contributed

Sewage workers: risk of acquiring enteric virus infections including hepatitis A.

PubMed

Divizia, Maurizio; Cencioni, Barbara; Palombi, Leonardo; Panà, Augusto

2008-07-01

To determine if sewage workers have an increased risk of acquiring viral infections, 66 workers at a small wastewater plant in north-eastern Italy and 72 control subjects recruited from blood donors were enrolled in a seroprevalence study to determine whether sewage workers are at increased risk of acquiring viral infections. In order to evaluate various risk factors, a questionnaire was filled out by each worker whereas seropositivity to Hepatitis A virus, Coxsackievirus B2 - B3 - B4 - B5, and Echovirus types 1 and 9 was determined in the laboratory. Anti-HAV antibodies were present in 37.8% of sewage workers and 36.1% of subjects in the control group. The difference was not statistically significant in the two groups, whereas a significant association was observed regarding age (P < 0.3). No association was observed with the occupational age, or with number and duration of contacts per day. The lack of evident occupational risk for hepatitis A among sewage workers may be explained by the adult age of the workers (mean age 41.3 years, range 22-58 years), and thus the antibody titre against different enteroviruses was determined. No statistically significant differences were evident with the raw values, but considering the 90 degrees percentile as a dichotomic value for the antibody levels a strong and significant association was present with Coxsackievirus B3 (O.R. 22.85, C.I. 95% 2.93-178.08) and Coxsackievirus B2 (O.R. 14.25, C.I. 95% 1.78-113.87). Analysis of the data confirms a limited risk of acquiring infection and/or disease but also the evident possibility of silent exposure to the viruses. The shift in HAV epidemiology and increased morbidity and mortality in adult age suggest that active immunization against hepatitis A should be considered.

Prevalence of Intestinal Parasite Infections among Individuals with Mental Retardation in New York State.

ERIC Educational Resources Information Center

Schupf, Nicole; And Others

1995-01-01

Prevalence of intestinal parasite infection among program participants of the New York State Office of Mental Retardation and Developmental Disabilities for 1986-87 was estimated at 7.3%, suggesting that management of parasitic infection is improving. Males and individuals with severe/profound mental retardation were twice as likely to have…

The Risk of Chronic Gastrointestinal Disorders Following Acute Infection with Intestinal Parasites

PubMed Central

Blitz, Jason; Riddle, Mark S.; Porter, Chad K.

2018-01-01

Background: Infectious gastroenteritis (IGE) is caused by numerous bacterial, viral, and parasitic pathogens. A history of IGE has been shown in previous studies to increase the risk of developing chronic gastrointestinal disorders and other chronic conditions. As bacteria and viruses represent the majority of pathogen-specific causes of IGE, post-infectious studies have primarily focused on these organisms. The objective of this study was to investigate an association between a history of parasite-associated IGE and the subsequent development of chronic post-infectious gastrointestinal and non-gastrointestinal disorders in a military population. Methods: International Classification of Diseases, 9th Revision Clinical Modification (ICD-9-CM) diagnostic coding data for primary exposures and outcomes were obtained for a retrospective cohort study of active component military personnel from 1998 to 2013. Exposed subjects consisted of individuals with documented infection with one of ten parasitic pathogens. Unexposed subjects were matched to exposed subjects on demographic and operational deployment history parameters. Adjusted odds ratios (aORs) were estimated using logistic regression for several chronic disorders previously shown to be associated with a history of IGE. Results: A total of 896 subjects with a parasitic exposure were matched to 3681 unexposed subjects for multivariate regression analysis. Individuals infected with Balantidium coli, Ascaris lumbricoides, Strongyloides stercoralis, Necator americanus/Ancylostoma duodenale, and Taenia spp. had higher aOR for development of several chronic gastrointestinal disorders when compared with unexposed subjects after controlling for various covariates. Conclusion: We found that parasite-associated enteric infection increases the risk of development of post-infectious chronic gastrointestinal disorders in a military population. These results require confirmation in similar populations and in the developing world

The Risk of Chronic Gastrointestinal Disorders Following Acute Infection with Intestinal Parasites.

PubMed

Blitz, Jason; Riddle, Mark S; Porter, Chad K

2018-01-01

Background: Infectious gastroenteritis (IGE) is caused by numerous bacterial, viral, and parasitic pathogens. A history of IGE has been shown in previous studies to increase the risk of developing chronic gastrointestinal disorders and other chronic conditions. As bacteria and viruses represent the majority of pathogen-specific causes of IGE, post-infectious studies have primarily focused on these organisms. The objective of this study was to investigate an association between a history of parasite-associated IGE and the subsequent development of chronic post-infectious gastrointestinal and non-gastrointestinal disorders in a military population. Methods: International Classification of Diseases, 9th Revision Clinical Modification (ICD-9-CM) diagnostic coding data for primary exposures and outcomes were obtained for a retrospective cohort study of active component military personnel from 1998 to 2013. Exposed subjects consisted of individuals with documented infection with one of ten parasitic pathogens. Unexposed subjects were matched to exposed subjects on demographic and operational deployment history parameters. Adjusted odds ratios (aORs) were estimated using logistic regression for several chronic disorders previously shown to be associated with a history of IGE. Results: A total of 896 subjects with a parasitic exposure were matched to 3681 unexposed subjects for multivariate regression analysis. Individuals infected with Balantidium coli , Ascaris lumbricoides , Strongyloides stercoralis , Necator americanus/Ancylostoma duodenale , and Taenia spp. had higher aOR for development of several chronic gastrointestinal disorders when compared with unexposed subjects after controlling for various covariates. Conclusion: We found that parasite-associated enteric infection increases the risk of development of post-infectious chronic gastrointestinal disorders in a military population. These results require confirmation in similar populations and in the developing

Marine netpen farming leads to infections with some unusual parasites.

PubMed

Kent, M L

2000-03-01

Marine netpen farming of salmonid fishes is a rapidly growing industry in several countries. With this relatively recent industry, new or unusual infections by parasitic pathogens have been observed. This is due to different hosts being reared in new geographic areas, or by indigenous species being reared in a different environmental condition, i.e. the marine netpen. Examples of the former include Kudoa thyrsites (Myxozoa) and Hemobaphes disphaerocephalus (Copepoda) infections in Atlantic salmon (Salmo salar) reared in the Pacific Northwest, Ceratothoa gaudichaudii (Isopoda) infections in Atlantic salmon reared in Chile, Neoparamoeba (=Paramoeba) sp. (Sacromastigophora) from salmonids reared in Tasmania, and Stephanostomum tenue (Digenea) infections in rainbow trout (Oncorhynchus mykiss) reared in Atlantic Canada. Chinook salmon (Oncorhynchus tshawytscha) reared in its native region, the Pacific Northwest, provides some examples of unusual or more severe infections than those normally seen in wild or freshwater reared chinook salmon. These include infections by Loma salmonae (Microsporidia), Gilguina squali (Cestoda) and the rosette agent, an undescribed fungus-like organism related to choanoflagellates. As the industry continues to expand, it is certain that more novel host-parasite relationships will be observed, providing challenges for fish farmers and parasitologists.

Mini-FLOTAC, an Innovative Direct Diagnostic Technique for Intestinal Parasitic Infections: Experience from the Field

PubMed Central

Barda, Beatrice Divina; Rinaldi, Laura; Ianniello, Davide; Zepherine, Henry; Salvo, Fulvio; Sadutshang, Tsetan; Cringoli, Giuseppe; Clementi, Massimo; Albonico, Marco

2013-01-01

Background Soil-transmitted helminths and intestinal protozoa infection are widespread in developing countries, yet an accurate diagnosis is rarely performed. The aim of this study was to evaluate the recently developed mini–FLOTAC method and to compare with currently more widely used techniques for the diagnosis of intestinal parasitic infections in different settings. Methodology/Principal Findings The study was carried out in Dharamsala, Himachal Pradesh, India, and in Bukumbi, Tanzania. A total of 180 pupils from two primary schools had their stool analyzed (n = 80 in Dharamsala and n = 100 in Bukumbi) for intestinal parasitic infections with three diagnostic methods: direct fecal smear, formol-ether concentration method (FECM) and mini-FLOTAC. Overall, 72% of the pupils were positive for any intestinal parasitic infection, 24% carried dual infections and 11% three infections or more. The most frequently encountered intestinal parasites were Entamoeba coli, Entamoeba histolytica/dispar, Giardia intestinalis, hookworm, (and Schistosoma mansoni, in Tanzania). Statistically significant differences were found in the detection of parasitic infections among the three methods: mini-FLOTAC was the most sensitive method for helminth infections (90% mini-FLOTAC, 60% FECM, and 30% direct fecal smear), whereas FECM was most sensitive for intestinal protozoa infections (88% FECM, 70% direct fecal smear, and 68% mini-FLOTAC). Conclusion/Significance We present the first experiences with the mini-FLOTAC for the diagnosis of intestinal helminths and protozoa. Our results suggest that it is a valid, sensitive and potentially low-cost alternative technique that could be used in resource-limited settings — particularly for helminth diagnosis. PMID:23936577

Opportunistic and non-opportunistic intestinal parasites in HIV/ AIDS patients in relation to their clinical and epidemiological status in a specialized medical service in Goiás, Brazil.

PubMed

Barcelos, Natane Barbosa; Silva, Lorena de Freitas E; Dias, Regyane Ferreira Guimarães; Menezes Filho, Hélio Ranes de; Rodrigues, Rosângela Maria

2018-03-08

Patients infected with the Human Immunodeficiency Virus (HIV) often have opportunistic infections, among which strongyloidiasis and coccidiosis are the most common parasitic infections that aggravate their health status. This study examined the prevalence of intestinal parasites, particularly of Strongyloides stercoralis and intestinal coccidia in patients with the Human Immunodeficiency Virus (HIV)/ Acquired Immunodeficiency Syndrome (AIDS) who were treated at the Specialized Assistance Service (SAE) of Jataí, State of Goiás, Brazil, and analyzed its correlation with clinical, laboratory, and socio-epidemiological parameters. A total of 270 stool samples were analyzed by the Lutz technique, Rugai's method, Agar Plate Culture, Ritchie's method and specific staining, Ziehl-Neelsen modified technique, Kinyoun's method and the rapid safranin method. The prevalence of intestinal parasites was 28.88% including 3.8% of S. stercoralis, Cryptosporidium sp. and Cystoisospora belli. There was a significant positive correlation between intestinal parasites and the clinical status and the use of antiretroviral therapy (ART), smoking, CD4+ lymphocyte counts and sexual orientation. In conclusion, the widespread use of antiretroviral therapy and health assistance contributed to the low prevalence of S. stercoralis and coccidiosis in patients with HIV/ AIDS who were followed up at the SAE.

The bacterial parasite Pasteuria ramosa is not killed if it fails to infect: implications for coevolution

PubMed Central

King, Kayla C; Auld, Stuart K J R; Wilson, Philip J; James, Janna; Little, Tom J

2013-01-01

Strong selection on parasites, as well as on hosts, is crucial for fueling coevolutionary dynamics. Selection will be especially strong if parasites that encounter resistant hosts are destroyed and diluted from the local environment. We tested whether spores of the bacterial parasite Pasteuria ramosa were passed through the gut (the route of infection) of their host, Daphnia magna, and whether passaged spores remained viable for a “second chance” at infecting a new host. In particular, we tested if this viability (estimated via infectivity) depended on host genotype, whether or not the genotype was susceptible, and on initial parasite dose. Our results show that Pasteuria spores generally remain viable after passage through both susceptible and resistant Daphnia. Furthermore, these spores remained infectious even after being frozen for several weeks. If parasites can get a second chance at infecting hosts in the wild, selection for infection success in the first instance will be reduced. This could also weaken reciprocal selection on hosts and slow the coevolutionary process. PMID:23467806

Changing trends in intestinal parasitic infections among long-term-residents and settled immigrants in Qatar

PubMed Central

2010-01-01

worrying trend in respect of both helminth and protozoan parasites was the increase in prevalence over the period 2005-2008, in helminth infections prevalence increasing 2-3 fold by 2008, and in protozoan infections by 1.5-2.0 fold. Conclusions We suggest that helminth infections are probably acquired abroad when immigrants visit their home villages, whilst protozoan infections are reinforced by transmission in Qatar, possibly in the poorer areas of the state where immigrant workers live. We discuss the significance of these findings and emphasize that they have clear implications for the health authorities. PMID:20946623

A novel approach to parasite population genetics: experimental infection reveals geographic differentiation, recombination and host-mediated population structure in Pasteuria ramosa, a bacterial parasite of Daphnia.

PubMed

Andras, J P; Ebert, D

2013-02-01

The population structure of parasites is central to the ecology and evolution of host-parasite systems. Here, we investigate the population genetics of Pasteuria ramosa, a bacterial parasite of Daphnia. We used natural P. ramosa spore banks from the sediments of two geographically well-separated ponds to experimentally infect a panel of Daphnia magna host clones whose resistance phenotypes were previously known. In this way, we were able to assess the population structure of P. ramosa based on geography, host resistance phenotype and host genotype. Overall, genetic diversity of P. ramosa was high, and nearly all infected D. magna hosted more than one parasite haplotype. On the basis of the observation of recombinant haplotypes and relatively low levels of linkage disequilibrium, we conclude that P. ramosa engages in substantial recombination. Isolates were strongly differentiated by pond, indicating that gene flow is spatially restricted. Pasteuria ramosa isolates within one pond were segregated completely based on the resistance phenotype of the host-a result that, to our knowledge, has not been previously reported for a nonhuman parasite. To assess the comparability of experimental infections with natural P. ramosa isolates, we examined the population structure of naturally infected D. magna native to one of the two source ponds. We found that experimental and natural infections of the same host resistance phenotype from the same source pond were indistinguishable, indicating that experimental infections provide a means to representatively sample the diversity of P. ramosa while reducing the sampling bias often associated with studies of parasite epidemics. These results expand our knowledge of this model parasite, provide important context for the large existing body of research on this system and will guide the design of future studies of this host-parasite system. © 2012 Blackwell Publishing Ltd.

Lactobacillus rhamnosus ingestion promotes innate host defense in an enteric parasitic infection.

PubMed

McClemens, Jessica; Kim, Janice J; Wang, Huaqing; Mao, Yu-Kang; Collins, Matthew; Kunze, Wolfgang; Bienenstock, John; Forsythe, Paul; Khan, Waliul I

2013-06-01

Enteric parasite infections around the world are a huge economic burden and decrease the quality of life for many people. The use of beneficial bacteria has attracted attention for their potential therapeutic applications in various diseases. However, the effects of beneficial bacteria in enteric parasitic infections remain largely unexplored. We investigated the effects of ingestion of Lactobacillus rhamnosus (JB-1) in a model of enteric nematode (Trichuris muris) infection. C57BL/6 (resistant to infection), AKR (susceptible to infection), interleukin 10 (IL-10) knockout (KO), and mucin Muc2 KO mice were infected with T. muris and treated orally with probiotic JB-1 or medium. The mice were sacrificed on various days postinfection to examine goblet cells, epithelial cell proliferation, cytokines, and worm burdens. Treatment with JB-1 significantly enhanced worm expulsion in resistant C57BL/6 mice, and this was associated with increases in IL-10 levels, goblet cell numbers, and epithelial cell proliferation. Beneficial effects of JB-1 were absent in IL-10 KO and resistant mice treated with γ-irradiated bacteria. Live JB-1 treatment also expedited worm expulsion in Muc2 KO mice and, more importantly, in AKR mice (susceptible to infection). Injection of IL-10 directly into the colonic tissue of uninfected mice induced goblet cell hyperplasia. These findings demonstrate that JB-1 modulates goblet cell biology and promotes parasite expulsion via an IL-10-mediated pathway and provide novel insights into probiotic effects on innate defense in nematode infection.

Using Proteomics to Understand How Leishmania Parasites Survive inside the Host and Establish Infection

PubMed Central

Veras, Patrícia Sampaio Tavares; Bezerra de Menezes, Juliana Perrone

2016-01-01

Leishmania is a protozoan parasite that causes a wide range of different clinical manifestations in mammalian hosts. It is a major public health risk on different continents and represents one of the most important neglected diseases. Due to the high toxicity of the drugs currently used, and in the light of increasing drug resistance, there is a critical need to develop new drugs and vaccines to control Leishmania infection. Over the past few years, proteomics has become an important tool to understand the underlying biology of Leishmania parasites and host interaction. The large-scale study of proteins, both in parasites and within the host in response to infection, can accelerate the discovery of new therapeutic targets. By studying the proteomes of host cells and tissues infected with Leishmania, as well as changes in protein profiles among promastigotes and amastigotes, scientists hope to better understand the biology involved in the parasite survival and the host-parasite interaction. This review demonstrates the feasibility of proteomics as an approach to identify new proteins involved in Leishmania differentiation and intracellular survival. PMID:27548150

Using Proteomics to Understand How Leishmania Parasites Survive inside the Host and Establish Infection.

PubMed

Veras, Patrícia Sampaio Tavares; Bezerra de Menezes, Juliana Perrone

2016-08-19

Leishmania is a protozoan parasite that causes a wide range of different clinical manifestations in mammalian hosts. It is a major public health risk on different continents and represents one of the most important neglected diseases. Due to the high toxicity of the drugs currently used, and in the light of increasing drug resistance, there is a critical need to develop new drugs and vaccines to control Leishmania infection. Over the past few years, proteomics has become an important tool to understand the underlying biology of Leishmania parasites and host interaction. The large-scale study of proteins, both in parasites and within the host in response to infection, can accelerate the discovery of new therapeutic targets. By studying the proteomes of host cells and tissues infected with Leishmania, as well as changes in protein profiles among promastigotes and amastigotes, scientists hope to better understand the biology involved in the parasite survival and the host-parasite interaction. This review demonstrates the feasibility of proteomics as an approach to identify new proteins involved in Leishmania differentiation and intracellular survival.

Evolution of a horizontally acquired legume gene, albumin 1, in the parasitic plant Phelipanche aegyptiaca and related species.

PubMed

Zhang, Yeting; Fernandez-Aparicio, Monica; Wafula, Eric K; Das, Malay; Jiao, Yuannian; Wickett, Norman J; Honaas, Loren A; Ralph, Paula E; Wojciechowski, Martin F; Timko, Michael P; Yoder, John I; Westwood, James H; Depamphilis, Claude W

2013-02-20

Parasitic plants, represented by several thousand species of angiosperms, use modified structures known as haustoria to tap into photosynthetic host plants and extract nutrients and water. As a result of their direct plant-plant connections with their host plant, parasitic plants have special opportunities for horizontal gene transfer, the nonsexual transmission of genetic material across species boundaries. There is increasing evidence that parasitic plants have served as recipients and donors of horizontal gene transfer (HGT), but the long-term impacts of eukaryotic HGT in parasitic plants are largely unknown. Here we show that a gene encoding albumin 1 KNOTTIN-like protein, closely related to the albumin 1 genes only known from papilionoid legumes, where they serve dual roles as food storage and insect toxin, was found in Phelipanche aegyptiaca and related parasitic species of family Orobanchaceae, and was likely acquired by a Phelipanche ancestor via HGT from a legume host based on phylogenetic analyses. The KNOTTINs are well known for their unique "disulfide through disulfide knot" structure and have been extensively studied in various contexts, including drug design. Genomic sequences from nine related parasite species were obtained, and 3D protein structure simulation tests and evolutionary constraint analyses were performed. The parasite gene we identified here retains the intron structure, six highly conserved cysteine residues necessary to form a KNOTTIN protein, and displays levels of purifying selection like those seen in legumes. The albumin 1 xenogene has evolved through >150 speciation events over ca. 16 million years, forming a small family of differentially expressed genes that may confer novel functions in the parasites. Moreover, further data show that a distantly related parasitic plant, Cuscuta, obtained two copies of albumin 1 KNOTTIN-like genes from legumes through a separate HGT event, suggesting that legume KNOTTIN structures have been

Influence of Hepatozoon parasites on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens☆

PubMed Central

Ferguson, Laura V.; Kirk Hillier, N.; Smith, Todd G.

2012-01-01

Hepatozoon species are heteroxenous parasites that commonly infect the blood of vertebrates and various organs of arthropods. Despite their ubiquity, little is known about how these parasites affect host phenotype, including whether or not these parasites induce changes in hosts to increase transmission success. The objectives of this research were to investigate influences of the frog blood parasite Hepatozoon clamatae and the snake blood parasite Hepatozoon sipedon on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens, respectively. During development of H. sipedon in C. pipiens, significantly fewer infected mosquitoes fed on uninfected snakes compared to uninfected mosquitoes. When H. sipedon was mature in C. pipiens, the number of infected and uninfected C. pipiens that fed on snakes was not significantly different. Higher numbers of mosquitoes fed on naturally infected snakes and frogs compared to laboratory-reared, uninfected control animals. However, experiments using only laboratory-raised frogs revealed that infection did not significantly affect host choice by C. territans. Behaviour of C. pipiens in the presence of H. sipedon may increase transmission success of the parasite and provide the first evidence of phenotypic changes in the invertebrate host of Hepatozoon parasites. PMID:24533317

Influence of Hepatozoon parasites on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens.

PubMed

Ferguson, Laura V; Kirk Hillier, N; Smith, Todd G

2013-12-01

Hepatozoon species are heteroxenous parasites that commonly infect the blood of vertebrates and various organs of arthropods. Despite their ubiquity, little is known about how these parasites affect host phenotype, including whether or not these parasites induce changes in hosts to increase transmission success. The objectives of this research were to investigate influences of the frog blood parasite Hepatozoon clamatae and the snake blood parasite Hepatozoon sipedon on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens, respectively. During development of H. sipedon in C. pipiens, significantly fewer infected mosquitoes fed on uninfected snakes compared to uninfected mosquitoes. When H. sipedon was mature in C. pipiens, the number of infected and uninfected C. pipiens that fed on snakes was not significantly different. Higher numbers of mosquitoes fed on naturally infected snakes and frogs compared to laboratory-reared, uninfected control animals. However, experiments using only laboratory-raised frogs revealed that infection did not significantly affect host choice by C. territans. Behaviour of C. pipiens in the presence of H. sipedon may increase transmission success of the parasite and provide the first evidence of phenotypic changes in the invertebrate host of Hepatozoon parasites.

Identification of malaria parasite-infected red blood cell surface aptamers by inertial microfluidic SELEX (I-SELEX)

NASA Astrophysics Data System (ADS)

Birch, Christina M.; Hou, Han Wei; Han, Jongyoon; Niles, Jacquin C.

2015-07-01

Plasmodium falciparum malaria parasites invade and remodel human red blood cells (RBCs) by trafficking parasite-synthesized proteins to the RBC surface. While these proteins mediate interactions with host cells that contribute to disease pathogenesis, the infected RBC surface proteome remains poorly characterized. Here we use a novel strategy (I-SELEX) to discover high affinity aptamers that selectively recognize distinct epitopes uniquely present on parasite-infected RBCs. Based on inertial focusing in spiral microfluidic channels, I-SELEX enables stringent partitioning of cells (efficiency ≥ 106) from unbound oligonucleotides at high volume throughput (~2 × 106 cells min-1). Using an RBC model displaying a single, non-native antigen and live malaria parasite-infected RBCs as targets, we establish suitability of this strategy for de novo aptamer selections. We demonstrate recovery of a diverse set of aptamers that recognize distinct, surface-displayed epitopes on parasite-infected RBCs with nanomolar affinity, including an aptamer against the protein responsible for placental sequestration, var2CSA. These findings validate I-SELEX as a broadly applicable aptamer discovery platform that enables identification of new reagents for mapping the parasite-infected RBC surface proteome at higher molecular resolution to potentially contribute to malaria diagnostics, therapeutics and vaccine efforts.

Cryptosporidium and other intestinal parasitic infections among HIV patients in southern Ethiopia: significance of improved HIV-related care.

PubMed

Shimelis, Techalew; Tassachew, Yayehyirad; Lambiyo, Tariku

2016-05-10

Intestinal parasitic infections are known to cause gastroenteritis, leading to higher morbidity and mortality, particularly in people living with HIV/AIDS. This study aimed to determine the prevalence of Cryptosporidium and other intestinal parasitic infections among HIV patients receiving care at a hospital in Ethiopia where previous available baseline data helps assess if improved HIV-related care has reduced infection rates. A cross-sectional study was conducted at Hawassa University Hospital in southern Ethiopia from May, 2013 to March, 2014. A consecutive sample of 491 HIV- infected patients with diarrhea or a CD4 T cell count < 200 cells/μl were prospectively studied. A single stool sample was collected from each study participant and processed using direct, formol-ether concentration, and modified Ziehl-Neelsen techniques for the diagnosis of Cryptosporidium and other intestinal parasites. The study was approved by the Institutional Review Board of the College of Medicine and Health Sciences, Hawassa University. Physicians managed participants found to be infected with any pathogenic intestinal parasite. The overall prevalence of intestinal parasitic infections among the study population was 35.8 %. The most prevalent parasites were Cryptosporidium (13.2 %), followed by Entamoeba histolytica/dispar (10.2 %), and Giardia lamblia (7.9 %). The rate of single and multiple infections were 25.5 and 10.3 %, respectively. Patients with a CD4 T cell count < 200 cells/μl had a similar rate of any intestinal parasitic infection or cryptosporidiosis compared to those with counts ≥ 200 cells/μl, but with some type of diarrhea. The study shows high prevalence of intestinal parasitic infections in the study population. However, the results in the current report are significantly lower compared to previous findings in the same hospital. The observed lower infection rate is encouraging and supports the need to strengthen and sustain the existing intervention

Recolonizing gray wolves increase parasite infection risk in their prey.

PubMed

Lesniak, Ines; Heckmann, Ilja; Franz, Mathias; Greenwood, Alex D; Heitlinger, Emanuel; Hofer, Heribert; Krone, Oliver

2018-02-01

The recent recolonization of Central Europe by the European gray wolf ( Canis lupus ) provides an opportunity to study the dynamics of parasite transmission for cases when a definitive host returns after a phase of local extinction. We investigated whether a newly established wolf population increased the prevalence of those parasites in ungulate intermediate hosts representing wolf prey, whether some parasite species are particularly well adapted to wolves, and the potential basis for such adaptations. We recorded Sarcocystis species richness in wolves and Sarcocystis prevalence in ungulates harvested in study sites with and without permanent wolf presence in Germany using microscopy and DNA metabarcoding. Sarcocystis prevalence in red deer ( Cervus elaphus ) was significantly higher in wolf areas (79.7%) than in control areas (26.3%) but not in roe deer ( Capreolus capreolus ) (97.2% vs. 90.4%) or wild boar ( Sus scrofa ) (82.8% vs. 64.9%). Of 11 Sarcocystis species, Sarcocystis taeniata and Sarcocystis grueneri occurred more often in wolves than expected from the Sarcocystis infection patterns of ungulate prey. Both Sarcocystis species showed a higher increase in prevalence in ungulates in wolf areas than other Sarcocystis species, suggesting that they are particularly well adapted to wolves, and are examples of "wolf specialists". Sarcocystis species richness in wolves was significantly higher in pups than in adults. "Wolf specialists" persisted during wolf maturation. The results of this study demonstrate that (1) predator-prey interactions influence parasite prevalence, if both predator and prey are part of the parasite life cycle, (2) mesopredators do not necessarily replace the apex predator in parasite transmission dynamics for particular parasites of which the apex predator is the definitive host, even if meso- and apex predators were from the same taxonomic family (here: Canidae, e.g., red foxes Vulpes vulpes ), and (3) age-dependent immune maturation

Dipylidium caninum mimicking recurrent enterobius vermicularis (pinworm) infection.

PubMed

Samkari, Ayman; Kiska, Deanna L; Riddell, Scott W; Wilson, Kathy; Weiner, Leonard B; Domachowske, Joseph B

2008-05-01

Pinworm infection is a very common diagnosis in young children that is not always confirmed through laboratory evaluation before empiric therapy is prescribed. This article describes a toddler who was treated several times for pinworms because small white worms were seen in her perianal area. Laboratory analysis of parasite material found in her diaper later confirmed a diagnosis of dipylidiasis. Because the signs of dipylidiasis and pinworm infection overlap and the treatments for these parasitic infections are different, the laboratory should clinically confirm suspected persistent or recurrent pinworms.

Geospatial distribution of intestinal parasitic infections in Rio de Janeiro (Brazil) and its association with social determinants

PubMed Central

Faria, Clarissa Perez; Zanini, Graziela Maria; Dias, Gisele Silva; da Silva, Sidnei; de Freitas, Marcelo Bessa; Almendra, Ricardo; Santana, Paula; Sousa, Maria do Céu

2017-01-01

Background Intestinal parasitic infections remain among the most common infectious diseases worldwide. This study aimed to estimate their prevalence and provide a detailed analysis of geographical distribution of intestinal parasites in the metropolitan region of Rio de Janeiro, considering demographic, socio-economic, and epidemiological contextual factors. Methods/Principal findings The cross-section survey was conducted among individuals attending the Evandro Chagas National Institute of Infectious Diseases (FIOCRUZ, RJ) during the period from April 2012 to February 2015. Stool samples were collected and processed by sedimentation, flotation, Kato-Katz, Baermann-Moraes and Graham methods, iron haematoxylin staining and safranin staining. Of the 3245 individuals analysed, 569 (17.5%) were infected with at least one parasite. The most common protozoa were Endolimax nana (28.8%), Entamoeba coli (14.8%), Complex Entamoeba histolytica/Entamoeba dispar (13.5%), Blastocystis hominis (12.7%), and Giardia lamblia (8.1%). Strongyloides stercoralis (4.3%), Schistosoma mansoni (3.3%), Ascaris lumbricoides (1.6%), and hookworms (1.5%) were the most frequent helminths. There was a high frequency of contamination by protozoa (87%), and multiple infections were observed in 141 participants (24.8%). A positive association between age (young children) and gender (male) with intestinal parasites was observed. Geospatial distribution of the detected intestinal parasitic infections was not random or homogeneous, but was influenced by socioeconomic conditions (through the material deprivation index (MDI)). Participants classified in the highest levels of deprivation had higher risk of having intestinal parasites. Conclusions/Significance This study provides the first epidemiological information on the prevalence and distribution of intestinal parasitic infections in the Rio de Janeiro metropolitan area. Intestinal parasites, especially protozoa, are highly prevalent, indicating that

Geospatial distribution of intestinal parasitic infections in Rio de Janeiro (Brazil) and its association with social determinants.

PubMed

Faria, Clarissa Perez; Zanini, Graziela Maria; Dias, Gisele Silva; da Silva, Sidnei; de Freitas, Marcelo Bessa; Almendra, Ricardo; Santana, Paula; Sousa, Maria do Céu

2017-03-01

Intestinal parasitic infections remain among the most common infectious diseases worldwide. This study aimed to estimate their prevalence and provide a detailed analysis of geographical distribution of intestinal parasites in the metropolitan region of Rio de Janeiro, considering demographic, socio-economic, and epidemiological contextual factors. The cross-section survey was conducted among individuals attending the Evandro Chagas National Institute of Infectious Diseases (FIOCRUZ, RJ) during the period from April 2012 to February 2015. Stool samples were collected and processed by sedimentation, flotation, Kato-Katz, Baermann-Moraes and Graham methods, iron haematoxylin staining and safranin staining. Of the 3245 individuals analysed, 569 (17.5%) were infected with at least one parasite. The most common protozoa were Endolimax nana (28.8%), Entamoeba coli (14.8%), Complex Entamoeba histolytica/Entamoeba dispar (13.5%), Blastocystis hominis (12.7%), and Giardia lamblia (8.1%). Strongyloides stercoralis (4.3%), Schistosoma mansoni (3.3%), Ascaris lumbricoides (1.6%), and hookworms (1.5%) were the most frequent helminths. There was a high frequency of contamination by protozoa (87%), and multiple infections were observed in 141 participants (24.8%). A positive association between age (young children) and gender (male) with intestinal parasites was observed. Geospatial distribution of the detected intestinal parasitic infections was not random or homogeneous, but was influenced by socioeconomic conditions (through the material deprivation index (MDI)). Participants classified in the highest levels of deprivation had higher risk of having intestinal parasites. This study provides the first epidemiological information on the prevalence and distribution of intestinal parasitic infections in the Rio de Janeiro metropolitan area. Intestinal parasites, especially protozoa, are highly prevalent, indicating that parasitic infections are still a serious public health problem

Report: Unsupervised identification of malaria parasites using computer vision.

PubMed

Khan, Najeed Ahmed; Pervaz, Hassan; Latif, Arsalan; Musharaff, Ayesha

2017-01-01

Malaria in human is a serious and fatal tropical disease. This disease results from Anopheles mosquitoes that are infected by Plasmodium species. The clinical diagnosis of malaria based on the history, symptoms and clinical findings must always be confirmed by laboratory diagnosis. Laboratory diagnosis of malaria involves identification of malaria parasite or its antigen / products in the blood of the patient. Manual diagnosis of malaria parasite by the pathologists has proven to become cumbersome. Therefore, there is a need of automatic, efficient and accurate identification of malaria parasite. In this paper, we proposed a computer vision based approach to identify the malaria parasite from light microscopy images. This research deals with the challenges involved in the automatic detection of malaria parasite tissues. Our proposed method is based on the pixel-based approach. We used K-means clustering (unsupervised approach) for the segmentation to identify malaria parasite tissues.

Intestinal parasitic infections: Current status and associated risk factors among school aged children in an archetypal African urban slum in Nigeria.

PubMed

Gyang, Vincent P; Chuang, Ting-Wu; Liao, Chien-Wei; Lee, Yueh-Lun; Akinwale, Olaoluwa P; Orok, Akwaowo; Ajibaye, Olusola; Babasola, Ajayi J; Cheng, Po-Ching; Chou, Chia-Mei; Huang, Ying-Chieh; Sonko, Pasaiko; Fan, Chia-Kwung

2017-06-22

Intestinal parasitic infections (IPIs) among school aged children (SAC) in Nigeria remains endemic, hence the need for regular surveillance to attract the attention of policy makers. This cross-sectional study investigated the current prevalence and factors associated with intestinal parasitic infections among school aged children in an urban slum of Lagos City, Nigeria. Single stool samples from 384 school aged children (188 boys and 196 girls) were examined by employing Merthiolate-iodine-formaldehyde concentration (MIFC) and Kato-Katz methods. Demographic characteristics and risk factors were obtained by questionnaires investigation. The overall prevalence was 86.2% in school children, out of them 39.1% had polyparasitism. IPIs showed the highest to the lowest prevalence of 62% (238/384), 25% (97/384), 12.3% (47/384), 11.8% (45/384), 9.9% (38/384), 8.4% (32/384), 3.4% (13/384), and 0.5% (2/384) found in Ascaris lumbricoides, Entamoeba histolytica/dispar, Giardia duodenalis, Endolimax nana, Entamoeba coli, Trichuris trichiura, Blastocystis hominis, and hookworm infections, respectively. MIFC technique showed superiority to Kato-Katz technique in the detection of IPIs (p < 0.0001). Drinking untreated water was a significant risk factor for these school aged children in acquiring protozoan infections after multivariate adjustment (OR = 1.86, 95% CI = 1.08-3.20, p = 0.02). Intestinal parasitic infections are very severe among school aged children in the urban slums, thus regular mass de-worming programs, health education, and the provision of safe drinking water is recommended to combat IPIs among the school aged children. Copyright © 2017. Published by Elsevier B.V.

Biophysics of malarial parasite exit from infected erythrocytes.

PubMed

Chandramohanadas, Rajesh; Park, YongKeun; Lui, Lena; Li, Ang; Quinn, David; Liew, Kingsley; Diez-Silva, Monica; Sung, Yongjin; Dao, Ming; Lim, Chwee Teck; Preiser, Peter Rainer; Suresh, Subra

2011-01-01

Upon infection and development within human erythrocytes, P. falciparum induces alterations to the infected RBC morphology and bio-mechanical properties to eventually rupture the host cells through parasitic and host derived proteases of cysteine and serine families. We used previously reported broad-spectrum inhibitors (E64d, EGTA-AM and chymostatin) to inhibit these proteases and impede rupture to analyze mechanical signatures associated with parasite escape. Treatment of late-stage iRBCs with E64d and EGTA-AM prevented rupture, resulted in no major RBC cytoskeletal reconfiguration but altered schizont morphology followed by dramatic re-distribution of three-dimensional refractive index (3D-RI) within the iRBC. These phenotypes demonstrated several-fold increased iRBC membrane flickering. In contrast, chymostatin treatment showed no 3D-RI changes and caused elevated fluctuations solely within the parasitophorous vacuole. We show that E64d and EGTA-AM supported PV breakdown and the resulting elevated fluctuations followed non-Gaussian pattern that resulted from direct merozoite impingement against the iRBC membrane. Optical trapping experiments highlighted reduced deformability of the iRBC membranes upon rupture-arrest, more specifically in the treatments that facilitated PV breakdown. Taken together, our experiments provide novel mechanistic interpretations on the role of parasitophorous vacuole in maintaining the spherical schizont morphology, the impact of PV breakdown on iRBC membrane fluctuations leading to eventual parasite escape and the evolution of membrane stiffness properties of host cells in which merozoites were irreversibly trapped, recourse to protease inhibitors. These findings provide a comprehensive, previously unavailable, body of information on the combined effects of biochemical and biophysical factors on parasite egress from iRBCs.

Role of Chemokines and Trafficking of Immune Cells in Parasitic Infections

PubMed Central

McGovern, Kathryn E.; Wilson, Emma H.

2014-01-01

Parasites are diverse eukaryotic pathogens that can have complex life cycles. Their clearance, or control within a mammalian host requires the coordinated effort of the immune system. The cell types recruited to areas of infection can combat the disease, promote parasite replication and survival, or contribute to disease pathology. Location and timing of cell recruitment can be crucial. In this review, we explore the role chemokines play in orchestrating and balancing the immune response to achieve optimal control of parasite replication without promoting pathology. PMID:25383073

Parasites contribute to ecologically dependent postmating isolation in the adaptive radiation of three-spined stickleback.

PubMed

El Nagar, Aliya; MacColl, Andrew D C

2016-08-17

Spatial variation in parasitic infections is common, and has the potential to drive population divergence and the reproductive isolation of hosts. However, despite support from theory and model laboratory systems, little strong evidence has been forthcoming from the wild. Here, we show that parasites are likely to cause reproductive isolation in the adaptive radiation of three-spined stickleback. Adjacent wild populations on the Scottish island of North Uist differ greatly and consistently in the occurrence of different parasites that have substantial effects on fitness. Laboratory-reared fish are more resistant to experimental infection by parasite species from their own population. Furthermore, hybrid backcrosses between the host populations are more resistant to parasites from the parental population to which they are more closely related. These patterns provide strong evidence that parasites can cause ecological speciation, by contributing to selection against migrants and ecologically dependent postmating isolation. © 2016 The Author(s).

An experimental approach to the immuno-modulatory basis of host-parasite local adaptation in tapeworm-infected sticklebacks.

PubMed

Hamley, Madeleine; Franke, Frederik; Kurtz, Joachim; Scharsack, Jörn Peter

2017-09-01

The evolutionary arms race of hosts and parasites often results in adaptations, which may differ between populations. Investigation of such local adaptation becomes increasingly important to understand dynamics of host-parasite interactions and co-evolution. To this end we performed an infection experiment involving pairs of three-spined sticklebacks and their tapeworm parasite Schistocephalus solidus from three geographically separated origins (Germany, Spain and Iceland) in a fully-crossed design for sympatric and allopatric host/parasite combinations. We hypothesized that local adaptation of the hosts results in differences in parasite resistance with variation in parasite infection rates and leukocyte activation, whereas parasites from different origins might differ in virulence reflected in host exploitation rates (parasite indices) and S. solidus excretory-secretory products (SsESP) involved in immune manipulation. In our experimental infections, sticklebacks from Iceland were more resistant to S. solidus infection compared to Spanish and German sticklebacks. Higher resistance of Icelandic sticklebacks seemed to depend on adaptive immunity, whereas sticklebacks of German origin, which were more heavily afflicted by S. solidus, showed elevated activity of innate immune traits. German S. solidus were less successful in infecting and exploiting allopatric hosts compared to their Icelandic and Spanish conspecifics. Nevertheless, exclusively SsESP from German S. solidus triggered significant in vitro responses of leukocytes from naïve sticklebacks. Interestingly, parasite indices were almost identical across the sympatric combinations. Differences in host resistance and parasite virulence between the origins were most evident in allopatric combinations and were consistent within origin; i.e. Icelandic sticklebacks were more resistant and their S. solidus were more virulent in all allopatric combinations, whereas German sticklebacks were less resistant and

Parasite infection rates of impala (Aepyceros melampus) in fenced game reserves in relation to reserve characteristics

USGS Publications Warehouse

Ezenwa, V.O.

2004-01-01

Under certain conditions reserves can pose a threat to wildlife conservation by increasing the transmission of parasites and pathogens. In this study, I investigated associations between reserve characteristics including area, density and species richness and parasite infection rates in impala (Aepyceros melampus). Using coprological methods to measure gastrointestinal parasitism rates of impala inhabiting five fully or partially fenced game reserves in central Kenya, I found that bovid species richness was correlated with parasite taxa richness across reserves, and that prevalence rates of multi-host strongyle nematodes were higher in reserves with more species. In addition, reserve size was also implicated as a potential predictor of infection risk. Overall, these results suggest that wildlife inhabiting highly diverse and small reserves may suffer from higher than normal rates of infection. Given the potential debilitating effects increases in parasitism can have on wildlife, these results underscore the importance of considering parasite transmission dynamics in the management of small, fenced protected areas. ?? 2003 Elsevier Ltd. All rights reserved.

Cestode parasites: application of in vivo and in vitro models for studies on the host-parasite relationship.

PubMed

Siles-Lucas, Mar; Hemphill, Andrew

2002-01-01

Cestode worms, commonly also known as 'flat' worms or tapeworms, are an important class of endoparasitic organisms. In order to complete their life cycle, they infect intermediate and definitive hosts in succession, through oral ingestion of eggs or larvae, respectively. Serious disease in humans or other mammalian hosts is mostly caused by the larval stages. Echinococcus spp. and Taenia spp. have been extensively investigated in the laboratory due to the fact that they represent important veterinary medical challenges and also cause grave diseases in humans. In contrast, Hymenolepis spp. and Mesocestoides spp. infections are relatively rare in humans, but these parasites have been extensively studied because their life cycle stages can be easily cultured in vitro, and can also be conveniently maintained in laboratory animal hosts. Thus they are more easily experimentally accessible, and represent important models for investigating the various aspects of cestode biology. This review will focus on in vitro and in vivo models which have been developed for studies on the host-parasite relationship during infection with Echinococcus, Taenia, Hymenolepis, Mesocestoides and Spirometra, and will cover the use of these models to investigate the morphology and ultrastructure of respective genera, the immunological relationship with the host and the development of vaccination approaches, as well as applications of these models for studies on parasite metabolism, physiology and gene expression. In addition, the use of these models in the development of chemotherapeutic measures against cestode infections is reviewed.

Parasite-mediated predation between native and invasive amphipods.

PubMed Central

MacNeil, Calum; Dick, Jaimie T A; Hatcher, Melanie J; Terry, Rebecca S; Smith, Judith E; Dunn, Alison M

2003-01-01

Parasites can structure biological communities directly through population regulation and indirectly by processes such as apparent competition. However, the role of parasites in the process of biological invasion is less well understood and mechanisms of parasite mediation of predation among hosts are unclear. Mutual predation between native and invading species is an important factor in determining the outcome of invasions in freshwater amphipod communities. Here, we show that parasites mediate mutual intraguild predation among native and invading species and may thereby facilitate the invasion process. We find that the native amphipod Gammarus duebeni celticus is host to a microsporidian parasite, Pleistophora sp. (new species), with a frequency of infection of 0-90%. However, the parasite does not infect three invading species, G. tigrinus, G. pulex and Crangonyx pseudogracilis. In field and laboratory manipulations, we show that the parasite exhibits cryptic virulence: the parasite does not affect host fitness in single-species populations, but virulence becomes apparent when the native and invading species interact. That is, infection has no direct effect on G. d. celticus survivorship, size or fecundity; however, in mixed-species experiments, parasitized natives show a reduced capacity to prey on the smaller invading species and are more likely to be preyed upon by the largest invading species. Thus, by altering dominance relationships and hierarchies of mutual predation, parasitism strongly influences, and has the potential to change, the outcome of biological invasions. PMID:12816645

Parasite (Ribeiroia ondatrae) infection linked to amphibian malformations in the western United States

USGS Publications Warehouse

Johnson, P.T.J.; Lunde, K.B.; Thurman, E.M.; Ritchie, E.G.; Wray, S.N.; Sutherland, D.R.; Kapfer, J.M.; Frest, T.J.; Bowerman, J.; Blaustein, A.R.

2002-01-01

Parasites and pathogens can influence the survivorship, behavior, and very structure of their host species. For example, experimental studies have shown that trematode parasites can cause high frequencies of severe limb malformations in amphibians. In a broad-scale field survey covering parts of California, Oregon, Washington, Idaho, and Montana, we examined relationships between the frequency and types of morphological abnormalities in amphibians and the abundance of trematode parasite infection, pH, concentrations of 61 pesticides, and levels of orthophosphate and total nitrate. We recorded severe malformations at frequencies ranging from 1% to 90% in nine amphibian species from 53 aquatic systems. Infection of larvae by the trematode Ribeiroia ondatrae was associated with, and functionally related to, higher frequencies of amphibian limb malformations than found in uninfected populations (≤5%). Parasites were concentrated around the basal tissue of hind limbs in infected anurans, and malformations associated with infection included skin webbings, supernumerary limbs and digits, and missing or malformed hind limbs. In the absence of Ribeiroia, amphibian populations exhibited low (0-5%) frequencies of abnormalities involving missing digits or distal portions of a hind limb. Species were affected differentially by the parasite, and Ambystoma macrodactylum, Hyla regilla, Rand aurora, R. luteiventris, and Taricha torosa typically exhibited the highest frequencies of abnormalities. None of the water-quality variables measured was associated with malformed amphibians, but aquatic snail hosts (Planorbella spp.) were significant predictors of the presence and abundance of Ribeiroia infection. Morphological comparisons of adult specimens of Ribeiroia collected from different sites and raised in experimental definitive hosts suggested that all samples represented the same species - R. ondatrae. These field results, coupled with experimental research on the effects of

Laboratory diagnostics of malaria

NASA Astrophysics Data System (ADS)

Siahaan, L.

2018-03-01

Even now, malaria treatment should only be administered after laboratory confirmation. There are several principal methods for diagnosing malaria. All these methods have their disadvantages.Presumptive treatment of malaria is widely practiced where laboratory tests are not readily available. Microscopy of Giemsa-stained thick and thin blood films remains the gold standard for the diagnosis of malaria infection. The technique of slide preparation, staining and reading are well known and standardized, and so is the estimate of the parasite density and parasite stages. Microscopy is not always available or feasible at primary health services in limited resource settings due to cost, lack of skilled manpower, accessories and reagents required. Rapid diagnostic tests (RDTs) are potential tools for parasite-based diagnosis since the tests are accurate in detecting malaria infections and are easy to use. The test is based on the capture of parasite antigen that released from parasitized red blood cells using monoclonal antibodies prepared against malaria antigen target. Polymerase Chain Reaction (PCR), depend on DNA amplification approaches and have higher sensitivity than microscopy. PCR it is not widely used due to the lack of a standardized methodology, high costs, and the need for highly-trained staff.

Lactobacillus rhamnosus Ingestion Promotes Innate Host Defense in an Enteric Parasitic Infection

PubMed Central

McClemens, Jessica; Kim, Janice J.; Wang, Huaqing; Mao, Yu-Kang; Collins, Matthew; Kunze, Wolfgang; Bienenstock, John

2013-01-01

Enteric parasite infections around the world are a huge economic burden and decrease the quality of life for many people. The use of beneficial bacteria has attracted attention for their potential therapeutic applications in various diseases. However, the effects of beneficial bacteria in enteric parasitic infections remain largely unexplored. We investigated the effects of ingestion of Lactobacillus rhamnosus (JB-1) in a model of enteric nematode (Trichuris muris) infection. C57BL/6 (resistant to infection), AKR (susceptible to infection), interleukin 10 (IL-10) knockout (KO), and mucin Muc2 KO mice were infected with T. muris and treated orally with probiotic JB-1 or medium. The mice were sacrificed on various days postinfection to examine goblet cells, epithelial cell proliferation, cytokines, and worm burdens. Treatment with JB-1 significantly enhanced worm expulsion in resistant C57BL/6 mice, and this was associated with increases in IL-10 levels, goblet cell numbers, and epithelial cell proliferation. Beneficial effects of JB-1 were absent in IL-10 KO and resistant mice treated with γ-irradiated bacteria. Live JB-1 treatment also expedited worm expulsion in Muc2 KO mice and, more importantly, in AKR mice (susceptible to infection). Injection of IL-10 directly into the colonic tissue of uninfected mice induced goblet cell hyperplasia. These findings demonstrate that JB-1 modulates goblet cell biology and promotes parasite expulsion via an IL-10-mediated pathway and provide novel insights into probiotic effects on innate defense in nematode infection. PMID:23536695

TGF-β signaling regulates resistance to parasitic nematode infection in Drosophila melanogaster.

PubMed

Eleftherianos, Ioannis; Castillo, Julio Cesar; Patrnogic, Jelena

2016-12-01

Over the past decade important advances have been made in the field of innate immunity; however, our appreciation of the signaling pathways and molecules that participate in host immune responses to parasitic nematode infections lags behind that of responses to microbial challenges. Here we have examined the regulation and immune activity of Transforming Growth Factor-beta (TGF-β) signaling in the model host Drosophila melanogaster upon infection with the nematode parasites Heterorhabditis gerrardi and H. bacteriophora containing their mutualistic bacteria Photorhabdus. We have found that the genes encoding the Activin and Bone Morphogenic Protein (BMP) ligands Dawdle (Daw) and Decapentaplegic (Dpp) are transcriptionally induced in flies responding to infection with the nematode parasites, containing or lacking their associated bacteria. We also show that deficient Daw or Dpp regulates the survival of D. melanogaster adults to the pathogens, whereas inactivation of Daw reduces the persistence of the nematodes in the mutant flies. These findings demonstrate a novel role for the TGF-β signaling pathways in the host anti-nematode immune response. Understanding the molecular mechanisms of host anti-nematode processes will potentially lead to the development of novel means for the efficient control of parasitic nematodes. Copyright © 2016 Elsevier GmbH. All rights reserved.

Human Parasitic Diseases in Bulgaria in Between 2013-2014.

PubMed

Rainova, Iskra; Harizanov, Rumen; Kaftandjiev, Iskren; Tsvetkova, Nina; Mikov, Ognyan; Kaneva, Eleonora

2018-01-20

In Bulgaria, more than 20 autochthonous human parasitic infections have been described and some of them are widespread. Over 50 imported protozoan and helminthic infections represent diagnostic and therapeutic challenges and pose epidemiological risks due to the possibility of local transmission. To establish the distribution of autochthonous and imported parasitic diseases among the population of the country over a 2-year period (2013-2014) and to evaluate their significance in the public health system. Cross sectional study. We used the annual reports by regional health inspectorates and data from the National Reference Laboratory at the National Centre of Infectious and Parasitic Diseases on all individuals infected with parasitic diseases in the country. Prevalence was calculated for parasitic diseases with few or absent clinical manifestations (oligosymptomatic or asymptomatic infections). Incidence per 100.000 was calculated for diseases with an overt clinical picture or those that required hospitalisation and specialised medical interventions (e.g. surgery). During the research period, parasitological studies were conducted on 1441.244 persons, and parasitic infections were diagnosed in 22.039 individuals. Distribution of various parasitic pathogens among the population displayed statistically significant differences in prevalence for some intestinal parasites (enterobiasis 0.81%, giardiasis 0.34% and blastocystosis 0.22%). For certain zoonotic diseases such as cystic echinococcosis (average incidence of 3.99 per 100.000) and trichinellosis (average incidence of 0.8 per 100.000), the incidence exceeds several times the annual incidence recorded in the European Union. Parasitic diseases still pose a substantial problem with social and medical impacts on the residents of our country. Improved efficiency regarding autochthonous and imported parasitic diseases is essential in providing the public health system the tools it needs to combat these diseases

The efficacy of eprinomectin extended-release injection against naturally acquired nematode parasites of cattle, with special regard to inhibited fourth-stage Ostertagia larvae.

PubMed

Hunter, J S; Yoon, S; Yazwinski, T A; Williams, J C; Rehbein, S

2013-03-01

The efficacy of eprinomectin in an extended-release injection (ERI) formulation in the treatment of cattle harboring naturally acquired nematode populations (including inhibited nematodes) was evaluated. Five studies were conducted under a similar protocol in the USA, the UK, and in Germany. All study animals were infected by grazing naturally contaminated pastures. The adequacy of pasture infectivity was confirmed by examining tracer calves prior to allocation and treatment of the study animals. The cattle were of various breeds or crosses, weighing 79-491 kg, and aged approximately 6-15 months. In each study, 20 animals were infected by grazing, and then removed from pasture and housed in a manner to preclude further nematode infections for 8-16 days until treatment. Animals were blocked based on descending pre-treatment body weight and randomly allocated to one of two treatments: ERI vehicle (control) at 1 mL/50 kg body weight or eprinomectin 5% (w/v) ERI at 1 mL/50 kg body weight (1.0 mg eprinomectin/kg). Treatments were administered once on Day 0 by subcutaneous injection in front of the shoulder. For parasite recovery and count, all study animals were humanely euthanized 14/15 days after treatment. Cattle treated with eprinomectin ERI had significantly (p<0.05) fewer of the following nematodes than the controls with overall reduction of parasite counts of ≥94%: adult Dictyocaulus viviparus, Capillaria spp., Cooperia oncophora, Cooperia pectinata, Cooperia punctata, Cooperia surnabada, Haemonchus placei, Nematodirus helvetianus, Oesophagostomum radiatum, Ostertagia lyrata, Ostertagia ostertagi, Trichostrongylus axei, Trichostrongylus colubriformis, Trichuris discolor, Trichuris skrjabini, and Trichuris spp.; developing fourth-stage larvae of Ostertagia spp. and Trichostrongylus spp.; and inhibited fourth-stage larvae of Cooperia spp., Haemonchus spp., Nematodirus spp., Oesophagostomum spp., Ostertagia spp., and Trichostrongylus spp. Animal treatments were

An Epidemiological Comparison of Parasitic Infection among Preschool Children in Four Areas in Lagos, Nigeria.

ERIC Educational Resources Information Center

Abidoye, R. O.

1995-01-01

Examined incidence of parasitic infections in school children in four contrasting areas of Lagos, Nigeria. Found that almost 40% of the infections identified were of the low socioeconomic status children. The 20 children from the higher socioeconomic status area, with the highest environmental sanitation, were without parasites. Twelve percent of…

Role of major histocompatibility complex class II in resistance of mice to naturally acquired infection with Syphacia obvelata

NASA Technical Reports Server (NTRS)

Stewart, Patricia W.; Chapes, Stephen K.

2003-01-01

Genetics plays a substantial role in host resistance in many host-parasite interactions. We examined the prevalence of naturally acquired infection with Syphacia obvelata in a number of mouse strains housed in a non-barrier facility. These mice, which included cross-bred and congenic, inbred strains on various genetic backgrounds, differ in the loci for the immune function genes--major histocompatibility complex class II (MHCII), toll-like receptor 4 (Tlr4), and solute carrier family 11, member 1 (Slc11a1)--which allowed comparisons of the impact of these genes on resistance to pinworm infection. Male and female mice of various ages were sampled over an 18-month period; infection was determined by use of the cellophane tape test. Results indicated that mice that were MHCII+/+ had a significantly lower prevalence of infection than did mice that were MHCII-/-. Differences were not seen between male and female mice. Although MHCII+/+ mice had an age-associated decrease in infection prevalence, such decrease was not seen in MHCII-/- mice. In contrast, infection prevalence in mice with the normal Tlr4 gene (Tlr4(LPS-n/LPS-n)) gene did not differ significantly compared with that in mice that were homozygous for either the point mutation (Tlr4(LPS-d/LPS-d)) or deletion (Tlr4(LPS-del/LPS-del)) of that gene. Likewise, the presence (Sle11a1r/r) or absence (Slc11a1s/s) of functional alleles for Slc11a1 had no effect on the prevalence of infection with S. obvelata. In conclusion, presence of MHCII, but not Tlr4 or Slc11a1 significantly influences prevalence of naturally acquired infection with S. obvelata. These data justify further comprehensive analyses of the immune components that are involved in pinworm resistance.

Toxoplasma gondii dissemination: a parasite's journey through the infected host.

PubMed

Harker, K S; Ueno, N; Lodoen, M B

2015-03-01

Toxoplasma gondii is a highly successful global pathogen that is remarkable in its ability to infect nearly any nucleated cell in any warm-blooded animal. Infection with T. gondii typically occurs through the ingestion of contaminated food or water, but the parasite then breaches the intestinal epithelial barrier and spreads from the lamina propria to a large variety of other organs in the body. A key feature of T. gondii pathogenesis is the parasite's ability to cross formidable biological barriers in the infected host and enter tissues such as the brain, eye and placenta. The dissemination of T. gondii into these organs underlies the severe disease that accompanies human toxoplasmosis. In this review, we will focus on seminal studies as well as exciting recent findings that have shaped our current understanding of the cellular and molecular mechanisms by which T. gondii journeys throughout the host and enters organs to cause disease. © 2014 John Wiley & Sons Ltd.

Predators, environment and host characteristics influence the probability of infection by an invasive castrating parasite.

PubMed

Gehman, Alyssa-Lois M; Grabowski, Jonathan H; Hughes, A Randall; Kimbro, David L; Piehler, Michael F; Byers, James E

2017-01-01

Not all hosts, communities or environments are equally hospitable for parasites. Direct and indirect interactions between parasites and their predators, competitors and the environment can influence variability in host exposure, susceptibility and subsequent infection, and these influences may vary across spatial scales. To determine the relative influences of abiotic, biotic and host characteristics on probability of infection across both local and estuary scales, we surveyed the oyster reef-dwelling mud crab Eurypanopeus depressus and its parasite Loxothylacus panopaei, an invasive castrating rhizocephalan, in a hierarchical design across >900 km of the southeastern USA. We quantified the density of hosts, predators of the parasite and host, the host's oyster reef habitat, and environmental variables that might affect the parasite either directly or indirectly on oyster reefs within 10 estuaries throughout this biogeographic range. Our analyses revealed that both between and within estuary-scale variation and host characteristics influenced L. panopaei prevalence. Several additional biotic and abiotic factors were positive predictors of infection, including predator abundance and the depth of water inundation over reefs at high tide. We demonstrate that in addition to host characteristics, biotic and abiotic community-level variables both serve as large-scale indicators of parasite dynamics.

The parasitic castration and gigantism of Lymnaea truncatula infected with the larval stages of Fasciola hepatica.

PubMed

Wilson, R A; Denison, J

1980-01-01

The shells of Lymnaea truncatula infected with the larval stages of Fasciola hepatica were significantly longer than those of comparable uninfected controls. The dry mass (tissue, shell + parasite) of the same infected snails, 56 days after infection, was approximately twice that of the controls (tissue + shell). The increased mass of infected snails was not due to a disproportionate increase in shell weight relative to tissues. Infected snails maintained at 20 degrees C had virtually ceased egg production by 21 days post-infection whereas control snails continued to lay eggs steadily for the duration of the experiment. The dry mass of snail tissue plus the cumulative dry weight of eggs produced was taken as an indication of the ability of control snails to generate biomass. Similarly the tissue mass plus cumulative egg weight and parasite weight was taken as an indication of the ability of the infected snails to generate biomass. The control and infected snails were not significantly different in this respect indicating that the gigantism of infected snails could be the result of a switch in nutrient supply from reproduction to somatic tissue growth and parasite growth. Castration was brought about 17-21 days after infection as a result of the direct consumption of the ovotestis by a proportion of the redial population. In a separate experiment it was demonstrated that a population of infected snails maintained at 20 degrees C survived as long as a similar group of control snails. The findings with this host-parasite system are discussed in relation to possible mechanisms causing castration and gigantism in other digene-snail interactions, and in relation to parasitic castration in other groups. It is concluded that the observed gigantism of infected snails is more likely to have a nutritional rather than endocrine origin.

Bone Marrow Is a Major Parasite Reservoir in Plasmodium vivax Infection

PubMed Central

2018-01-01

ABSTRACT Plasmodium vivax causes heavy burdens of disease across malarious regions worldwide. Mature P. vivax asexual and transmissive gametocyte stages occur in the blood circulation, and it is often assumed that accumulation/sequestration in tissues is not an important phase in their development. Here, we present a systematic study of P. vivax stage distributions in infected tissues of nonhuman primate (NHP) malaria models as well as in blood from human infections. In a comparative analysis of the transcriptomes of P. vivax and Plasmodium falciparum blood-stage parasites, we found a conserved cascade of stage-specific gene expression despite the greatly different gametocyte maturity times of these two species. Using this knowledge, we validated a set of conserved asexual- and gametocyte-stage markers both by quantitative real-time PCR and by antibody assays of peripheral blood samples from infected patients and NHP (Aotus sp.). Histological analyses of P. vivax parasites in organs of 13 infected NHP (Aotus and Saimiri species) demonstrated a major fraction of immature gametocytes in the parenchyma of the bone marrow, while asexual schizont forms were enriched to a somewhat lesser extent in this region of the bone marrow as well as in sinusoids of the liver. These findings suggest that the bone marrow is an important reservoir for gametocyte development and proliferation of malaria parasites. PMID:29739900

Infectivity of Plasmodium falciparum in Malaria-Naive Individuals Is Related to Knob Expression and Cytoadherence of the Parasite

PubMed Central

Stanisic, Danielle I.; Gerrard, John; Fink, James; Griffin, Paul M.; Liu, Xue Q.; Sundac, Lana; Sekuloski, Silvana; Rodriguez, Ingrid B.; Pingnet, Jolien; Yang, Yuedong; Zhou, Yaoqi; Trenholme, Katharine R.; Wang, Claire Y. T.; Hackett, Hazel; Chan, Jo-Anne A.; Langer, Christine; Hanssen, Eric; Hoffman, Stephen L.; Beeson, James G.; McCarthy, James S.

2016-01-01

Plasmodium falciparum is the most virulent human malaria parasite because of its ability to cytoadhere in the microvasculature. Nonhuman primate studies demonstrated relationships among knob expression, cytoadherence, and infectivity. This has not been examined in humans. Cultured clinical-grade P. falciparum parasites (NF54, 7G8, and 3D7B) and ex vivo-derived cell banks were characterized. Knob and knob-associated histidine-rich protein expression, CD36 adhesion, and antibody recognition of parasitized erythrocytes (PEs) were evaluated. Parasites from the cell banks were administered to malaria-naive human volunteers to explore infectivity. For the NF54 and 3D7B cell banks, blood was collected from the study participants for in vitro characterization. All parasites were infective in vivo. However, infectivity of NF54 was dramatically reduced. In vitro characterization revealed that unlike other cell bank parasites, NF54 PEs lacked knobs and did not cytoadhere. Recognition of NF54 PEs by immune sera was observed, suggesting P. falciparum erythrocyte membrane protein 1 expression. Subsequent recovery of knob expression and CD36-mediated adhesion were observed in PEs derived from participants infected with NF54. Knobless cell bank parasites have a dramatic reduction in infectivity and the ability to adhere to CD36. Subsequent infection of malaria-naive volunteers restored knob expression and CD36-mediated cytoadherence, thereby showing that the human environment can modulate virulence. PMID:27382019

Spatio-temporal analysis of small-area intestinal parasites infections in Ghana.

PubMed

Osei, F B; Stein, A

2017-09-22

Intestinal parasites infection is a major public health burden in low and middle-income countries. In Ghana, it is amongst the top five morbidities. In order to optimize scarce resources, reliable information on its geographical distribution is needed to guide periodic mass drug administration to populations of high risk. We analyzed district level morbidities of intestinal parasites between 2010 and 2014 using exploratory spatial analysis and geostatistics. We found a significantly positive Moran's Index of spatial autocorrelation for each year, suggesting that adjoining districts have similar risk levels. Using local Moran's Index, we found high-high clusters extending towards the Guinea and Sudan Savannah ecological zones, whereas low-low clusters extended within the semi-deciduous forest and transitional ecological zones. Variograms indicated that local and regional scale risk factors modulate the variation of intestinal parasites. Poisson kriging maps showed smoothed spatially varied distribution of intestinal parasites risk. These emphasize the need for a follow-up investigation into the exact determining factors modulating the observed patterns. The findings also underscored the potential of exploratory spatial analysis and geostatistics as tools for visualizing the spatial distribution of small area intestinal worms infections.

Disease severity in patients with visceral leishmaniasis is not altered by co-infection with intestinal parasites.

PubMed

Tajebe, Fitsumbrhan; Getahun, Mulusew; Adem, Emebet; Hailu, Asrat; Lemma, Mulualem; Fikre, Helina; Raynes, John; Tamiru, Aschalew; Mulugeta, Zemenay; Diro, Ermias; Toulza, Frederic; Shkedy, Ziv; Ayele, Tadesse; Modolell, Manuel; Munder, Markus; Müller, Ingrid; Takele, Yegnasew; Kropf, Pascale

2017-07-01

Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was similar to VL patients co-infected with intestinal parasites, suggesting that co-infection of VL patients with intestinal parasites does not alter disease severity.

Disease severity in patients with visceral leishmaniasis is not altered by co-infection with intestinal parasites

PubMed Central

Adem, Emebet; Hailu, Asrat; Lemma, Mulualem; Fikre, Helina; Raynes, John; Tamiru, Aschalew; Mulugeta, Zemenay; Diro, Ermias; Toulza, Frederic; Shkedy, Ziv; Ayele, Tadesse; Modolell, Manuel; Munder, Markus; Müller, Ingrid; Takele, Yegnasew

2017-01-01

Visceral leishmaniasis (VL) is a neglected tropical disease that affects the poorest communities and can cause substantial morbidity and mortality. Visceral leishmaniasis is characterized by the presence of Leishmania parasites in the spleen, liver and bone marrow, hepatosplenomegaly, pancytopenia, prolonged fever, systemic inflammation and low body mass index (BMI). The factors impacting on the severity of VL are poorly characterized. Here we performed a cross-sectional study to assess whether co-infection of VL patients with intestinal parasites influences disease severity, assessed with clinical and haematological data, inflammation, cytokine profiles and BMI. Data from VL patients was similar to VL patients co-infected with intestinal parasites, suggesting that co-infection of VL patients with intestinal parasites does not alter disease severity. PMID:28732017

Expression of parasite genetic variation changes over the course of infection: implications of within-host dynamics for the evolution of virulence

PubMed Central

Clerc, Melanie; Ebert, Dieter; Hall, Matthew D.

2015-01-01

How infectious disease agents interact with their host changes during the course of infection and can alter the expression of disease-related traits. Yet by measuring parasite life-history traits at one or few moments during infection, studies have overlooked the impact of variable parasite growth trajectories on disease evolution. Here we show that infection-age-specific estimates of host and parasite fitness components can reveal new insight into the evolution of parasites. We do so by characterizing the within-host dynamics over an entire infection period for five genotypes of the castrating bacterial parasite Pasteuria ramosa infecting the crustacean Daphnia magna. Our results reveal that genetic variation for parasite-induced gigantism, host castration and parasite spore loads increases with the age of infection. Driving these patterns appears to be variation in how well the parasite maintains control of host reproduction late in the infection process. We discuss the evolutionary consequences of this finding with regard to natural selection acting on different ages of infection and the mechanism underlying the maintenance of castration efficiency. Our results highlight how elucidating within-host dynamics can shed light on the selective forces that shape infection strategies and the evolution of virulence. PMID:25761710

Expression of parasite genetic variation changes over the course of infection: implications of within-host dynamics for the evolution of virulence.

PubMed

Clerc, Melanie; Ebert, Dieter; Hall, Matthew D

2015-04-07

How infectious disease agents interact with their host changes during the course of infection and can alter the expression of disease-related traits. Yet by measuring parasite life-history traits at one or few moments during infection, studies have overlooked the impact of variable parasite growth trajectories on disease evolution. Here we show that infection-age-specific estimates of host and parasite fitness components can reveal new insight into the evolution of parasites. We do so by characterizing the within-host dynamics over an entire infection period for five genotypes of the castrating bacterial parasite Pasteuria ramosa infecting the crustacean Daphnia magna. Our results reveal that genetic variation for parasite-induced gigantism, host castration and parasite spore loads increases with the age of infection. Driving these patterns appears to be variation in how well the parasite maintains control of host reproduction late in the infection process. We discuss the evolutionary consequences of this finding with regard to natural selection acting on different ages of infection and the mechanism underlying the maintenance of castration efficiency. Our results highlight how elucidating within-host dynamics can shed light on the selective forces that shape infection strategies and the evolution of virulence. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Parasite distribution and associated immune response during the acute phase of Toxoplasma gondii infection in sheep.

PubMed

Verhelst, Delfien; De Craeye, Stéphane; Entrican, Gary; Dorny, Pierre; Cox, Eric

2014-12-16

In many countries, Toxoplasma gondii (T. gondii) is a major cause of reproductive disorders and abortions in the sheep industry, and therefore responsible for important financial and economic losses. In addition, undercooked infected lamb is an important risk factor for human toxoplasmosis. In the present study, the initial phase of the infection was investigated: the parasite's entry site, the subsequent distribution of the parasite and the host-immune response. Parasite DNA was already detected in the cranial small intestinal mucosa the first days after oral infection with T. gondii tissue cysts. Simultaneously, high IFN-gamma and IL-12 responses were induced mainly in the mesenteric lymph nodes. The emergence of IgG1 (at 8dpi), and IgG2 (at 11 dpi) was accompanied by a decrease or even disappearance of the IFN-gamma and IL-12 response in the Peyers' patches (PP), PBMC's and popliteal LN's. Meanwhile the parasite DNA could be recovered from most mucosal and systemic tissues to become undetectable in the small intestine, popliteal LN, PBMC and spleen 3 weeks pi. Our results indicate that parasites enter the cranial small intestine the first days after infection and that after an increase the first two weeks after infection, the parasite DNA levels in the intestine drop below the detection limit three weeks after infection. This coincides with an increase in parastic-specific serum IgG1 and IgG2 and a decrease of the antigen-specific IFN-gamma response in PP, PBMC and popliteal LN. We suggest a role for IFN-gamma and IL-12 in controlling the infection.

Breast milk-acquired cytomegalovirus infection and disease in VLBW and premature infants.

PubMed

Lanzieri, Tatiana M; Dollard, Sheila C; Josephson, Cassandra D; Schmid, D Scott; Bialek, Stephanie R

2013-06-01

Very low birth weight (VLBW) and premature infants are at risk for developing postnatal cytomegalovirus (CMV) disease, including CMV-related sepsis-like syndrome (CMV-SLS) for which estimates [corrected] in the United States are lacking. We performed a systematic review and meta-analysis to estimate the pooled proportions (and 95% confidence intervals) of VLBW and premature infants born to CMV-seropositive women with breast milk-acquired CMV infection and CMV-SLS. We combined these proportions with population-based rates of CMV seropositivity, breast milk feeding, VLBW, and prematurity to estimate annual rates of breast milk-acquired CMV infection and CMV-SLS in the United States. In our meta-analysis, among 299 infants fed untreated breast milk, we estimated 19% (11%-32%) acquired CMV infection and 4% (2%-7%) developed CMV-SLS. Assuming these proportions, we estimated a rate of breast milk-acquired CMV infection among VLBW and premature infants in the United States of 6.5% (3.7%-10.9%) and 1.4% (0.7%-2.4%) of CMV-SLS, corresponding to 600 infants with CMV-SLS in 2008. Among 212 infants fed frozen breast milk, our meta-analysis proportions were 13% (7%-24%) for infection and 5% (2%-12%) for CMV-SLS, yielding slightly lower rates of breast milk-acquired CMV infection (4.4%; 2.4%-8.2%) but similar rates of CMV-SLS (1.7%; 0.7%-4.1%). Breast milk-acquired CMV infection presenting with CMV-SLS is relatively rare. Prospective studies to better define the burden of disease are needed to refine guidelines for feeding breast milk from CMV-seropositive mothers to VLBW and premature infants.

A survey of gastro-intestinal parasitic infection in domestic and wild birds in Chittagong and Greater Sylhet, Bangladesh.

PubMed

Hoque, Md Ahasanul; Hassan, Mohammad Mahmudul; Haque, Enamul; Shaikat, Amir Hossan; Khan, Shahneaz Ali; Alim, Abdul; Skerratt, Lee Francis; Islam, Ariful; Tun, Hein Min; Dissanayake, Ravi; Day, Tapan Kumar; Debnath, Nitish Chandra; Yamage, Mat

2014-11-01

A survey of gastrointestinal parasitic infection as determined by faecal examination was conducted among domestic and wild birds in Bangladesh. Birds were sampled from households, wet markets and wetlands in Chittagong and Greater Sylhet districts during April 2012 to February 2013. Mist nets were used to catch resident wild and migratory birds. The overall prevalence of parasitic infection ranged among locations from 25 to 55% in indigenous domestic ducks (live bird samples=304), 20% in resident wild birds (environmental faecal samples=40) and 40% in migratory birds (live bird samples=35). The prevalence of parasitic infection was significantly higher in indigenous domestic ducks collected during summer (39%) than winter (22%) (p=0.04). In domestic indigenous ducks and Muscovy ducks, both single and multiple types of parasitic infections were found. However, other domestic birds and wild birds often had a single type of parasitic infection. Ascaridia spp. with an average egg load of 50-900, was commonly detected in faecal samples of domestic and wild birds in this study. Other identified parasites were Capillaria spp. and Heterakis spp. both in domestic and wild birds. Improvement of biosecurity measures for household duck farms through educating and motivating household farmers could help mitigate the effects of parasitic infection on production. Copyright © 2014 Elsevier B.V. All rights reserved.

A cross-sectional study of intestinal parasitic infections in a rural district of west China

PubMed Central

Tang, Ning; Luo, Nian Ji

2003-01-01

BACKGROUND: Parasitic infections are widespread in rural areas of West China. The remote and humid environment, traditional ways of life, contaminated potable water and limited health services all contribute to the transmission and persistence of fecal parasites. OBJECTIVE: To describe the prevalence of intestinal parasitic infections in an area of West China, including its associations with demographic variables. METHODS: Single fecal specimens were collected using a previously validated kit. Parasites were detected microscopically by iodine-stained smear, modified Kato-Katz thick smear, simple saline smear, test tube filter paper culture and adhesive cellophane tape anal swab. RESULTS: The prevalence of enteric parasites in the population was 51.7%. The proportion of individuals infected with one parasite was 36.5%, two parasites 12.7%, three parasites 3.0% and four parasites 0.08%. Parasites identified included Ascaris lumbricoides in 41.4% of all individuals tested, Ancylostoma duodenale in 17.7%, Trichurias trichuria in 8.25%, Enterobius vermicularis in 0.43%, Blastocystis hominis in 1.37%, Entamoeba coli in 0.47%, Entamoeba histolytica in 0.16%, Giardia lamblia in 0.04%, Strongyloides stercoralis in 0.04% and Clonorchis sinensis in 0.04%. The prevalence was significantly increased in women, people aged 15 to 19 years and over 80 years, the rural farm population, farmers, preschool and primary school groups, residents of a hilly rather than mountainous or plains terrain, and in intermediate income groups. The prevalence was significantly negatively associated with educational level, but not with age or income. CONCLUSIONS: This study supports the use of simple fecal examinations to monitor the parasite burden in rural areas of developing countries. Enteric parasites remain common in this population in rural China. PMID:18159450

Molecular epidemiology of newly acquired hepatitis C infections in England 2008-2011: genotype, phylogeny and mutation analysis.

PubMed

May, Shoshanna; Ngui, Siew Lin; Collins, Sarah; Lattimore, Sam; Ramsay, Mary; Tedder, Richard S; Ijaz, Samreen

2015-03-01

Analysis of laboratory testing data collected through the Sentinel Surveillance programme has provided a method for identifying individuals who have recently acquired their hepatitis C virus (HCV) infection. Access to samples from these individuals provided a rare opportunity to undertake molecular characterization studies. To describe the epidemiology and genetic diversity of hepatitis C in recent seroconverter infections and to predict how this will impact on HCV treatment and control. One hundred and forty seven samples were available from individuals, identified to have recently acquired their HCV infection. Genotype determination with additional phylogenetic analysis was carried out on NS5B sequences. Analysis across the NS3 region investigated the presence of antiviral resistance mutations. Where possible, molecular data was linked to demographic and risk/behavioural factor information. The majority of new infections occurred in males with a mean age of 37 years. The most commonly observed genotypes were 1a (49%) and 3a (42%) and injecting drug use (58%) was the most common risk factor. Genotype distribution differed between persons who inject drugs and those with other risk factors suggesting two possible epidemics. Phylogenetic analysis indicated possible transmission networks within specific risk groups. Amino acid changes associated with antiviral resistance were noted in the NS3 region in some samples. Continued surveillance of linked molecular, virological, demographic and epidemiological information on recently acquired infections will contribute to understanding the on-going HCV epidemic in England. Copyright © 2015 Elsevier B.V. All rights reserved.

Two's a crowd? Crowding effect in a parasitic castrator drives differences in reproductive resource allocation in single vs double infections.

PubMed

Fong, Caitlin R; Moron, Nancy A; Kuris, Armand M

2017-04-01

The 'crowding effect' is a result of competition by parasites within a host for finite resources. Typically, the severity of this effect increases with increasing numbers of parasites within a host and manifests in reduced body size and thus fitness. Evidence for the crowding effect is mixed - while some have found negative effects, others have found a positive effect of increased parasite load on parasite fitness. Parasites are consumers with diverse trophic strategies reflected in their life history traits. These distinctions are useful to predict the effects of crowding. We studied a parasitic castrator, a parasite that usurps host reproductive energy and renders the host sterile. Parasitic castrators typically occur as single infections within hosts. With multiple parasitic castrators, we expect strong competition and evidence of crowding. We directly assess the effect of crowding on reproductive success in a barnacle population infected by a unique parasitic castrator, Hemioniscus balani, an isopod parasite that infects and blocks reproduction of barnacles. We find (1) strong evidence of crowding in double infections, (2) increased frequency of double infections in larger barnacle hosts with more resources and (3) perfect compensation in egg production, supporting strong space limitation. Our results document that the effects of crowding are particularly severe for this parasitic castrator, and may be applicable to other castrators that are also resource or space limited.

Tracking transparent monogenean parasites on fish from infection to maturity

PubMed Central

Trujillo-González, Alejandro; Constantinoiu, Constantin C.; Rowe, Richard; Hutson, Kate S.

2015-01-01

The infection dynamics and distribution of the ectoparasitic fish monogenean Neobenedenia sp. (Monogenea: Capsalidae) throughout its development was examined on barramundi, Lates calcarifer (Bloch) (Latidae), by labelling transparent, ciliated larvae (oncomiracidia) with a fluorescent dye. Replicate fish were each exposed to approximately 50 fluorescent oncomiracidia and then examined for parasites using an epifluorescence stereomicroscope at 10 time intervals post-exposure (15, 30, 60, 120 min, 24, 48 h, four, eight, 12, and 16 days). Fluorescent labelling revealed that parasites attached underneath and on the surface of the scales of host fish. Parasite infection success was 20% within 15 min, and peaked at 93% two days post-exposure, before gradually declining between four and sixteen days. Differences in parasite distribution on L. calcarifer over time provided strong evidence that Neobenedenia sp. larvae settled opportunistically and then migrated to specific microhabitats. Parasites initially attached (<24 h) in greater mean numbers on the body surface (13 ± 1.5) compared to the fins (4 ± 0.42) and head region (2 ± 0.41). Once larvae recruitment had ceased (48 h), there were significantly higher mean post-larvae counts on the head (5 ± 3.4) and fins (12 ± 3) compared to previous time intervals. Neobenedenia sp. aggregated on the eyes, fins, and dorsal and ventral extremities on the main body. As parasites neared sexual maturity, there was a marked aggregation on the fins (22 ± 2.35) compared to the head (4 ± 0.97) and body (9 ± 1.33), indicating that Neobenedenia sp. may form mating aggregations. PMID:26199875

Long-Term Disease Dynamics for a Specialized Parasite of Ant Societies: A Field Study

PubMed Central

Loreto, Raquel G.; Elliot, Simon L.; Freitas, Mayara L. R.; Pereira, Thairine M.; Hughes, David P.

2014-01-01

Many studies have investigated how social insects behave when a parasite is introduced into their colonies. These studies have been conducted in the laboratory, and we still have a limited understanding of the dynamics of ant-parasite interactions under natural conditions. Here we consider a specialized parasite of ant societies (Ophiocordyceps camponoti-rufipedis infecting Camponotus rufipes) within a rainforest. We first established that the parasite is unable to develop to transmission stage when introduced within the host nest. Secondly, we surveyed all colonies in the studied area and recorded 100% prevalence at the colony level (all colonies were infected). Finally, we conducted a long-term detailed census of parasite pressure, by mapping the position of infected dead ants and foraging trails (future hosts) in the immediate vicinity of the colonies over 20 months. We report new dead infected ants for all the months we conducted the census – at an average of 14.5 cadavers/month/colony. Based on the low infection rate, the absence of colony collapse or complete recovery of the colonies, we suggest that this parasite represents a chronic infection in the ant societies. We also proposed a “terminal host model of transmission” that links the age-related polyethism to the persistence of a parasitic infection. PMID:25133749

Disentangling complex parasite interactions: Protection against cerebral malaria by one helminth species is jeopardized by co-infection with another.

PubMed

Abbate, Jessica L; Ezenwa, Vanessa O; Guégan, Jean-François; Choisy, Marc; Nacher, Mathieu; Roche, Benjamin

2018-05-01

Multi-species interactions can often have non-intuitive consequences. However, the study of parasite interactions has rarely gone beyond the effects of pairwise combinations of species, and the outcomes of multi-parasite interactions are poorly understood. We investigated the effects of co-infection by four gastrointestinal helminth species on the development of cerebral malaria among Plasmodium falciparum-infected patients. We characterized associations among the helminth parasite infra-community, and then tested for independent (direct) and co-infection dependent (indirect) effects of helminths on cerebral malaria risk. We found that infection by Ascaris lumbricoides and Trichuris trichiura were both associated with direct reductions in cerebral malaria risk. However, the benefit of T. trichiura infection was halved in the presence of hookworm, revealing a strong indirect effect. Our study suggests that the outcome of interactions between two parasite species can be significantly modified by a third, emphasizing the critical role that parasite community interactions play in shaping infection outcomes.

Candida bloodstream infection: a clinical microbiology laboratory perspective.

PubMed

Pongrácz, Júlia; Kristóf, Katalin

2014-09-01

The incidence of Candida bloodstream infection (BSI) has been on the rise in several countries worldwide. Species distribution is changing; an increase in the percentage of non-albicans species, mainly fluconazole non-susceptible C. glabrata was reported. Existing microbiology diagnostic methods lack sensitivity, and new methods need to be developed or further evaluation for routine application is necessary. Although reliable, standardized methods for antifungal susceptibility testing are available, the determination of clinical breakpoints remains challenging. Correct species identification is important and provides information on the intrinsic susceptibility profile of the isolate. Currently, acquired resistance in clinical Candida isolates is rare, but reports indicate that it could be an issue in the future. The role of the clinical microbiology laboratory is to isolate and correctly identify the infective agent and provide relevant and reliable susceptibility data as soon as possible to guide antifungal therapy.

Role of parasitic vaccines in integrated control of parasitic diseases in livestock

PubMed Central

Sharma, Neelu; Singh, Veer; Shyma, K. P.

2015-01-01

Parasitic infections adversely affect animal’s health and threaten profitable animal production, thus affecting the economy of our country. These infections also play a major role in the spread of zoonotic diseases. Parasitic infections cause severe morbidity and mortality in animals especially those affecting the gastrointestinal system and thus affect the economy of livestock owner by decreasing the ability of the farmer to produce economically useful animal products. Due to all these reasons proper control of parasitic infection is critically important for sustained animal production. The most common and regularly used method to control parasitic infection is chemotherapy, which is very effective but has several disadvantages like drug resistance and drug residues. Integrated approaches to control parasitic infections should be formulated including grazing management, biological control, genetic resistance of hosts, and parasitic vaccines. India ranks first in cattle and buffalo population, but the majority of livestock owners have fewer herds, so other measures like grazing management, biological control, genetic resistance of hosts are not much practical to use. The most sustainable and economical approach to control parasitic infection in our country is to vaccinate animals, although vaccines increase the initial cost, but the immunity offered by the vaccine are long lived. Thus, vaccination of animals for various clinical, chronic, subclinical parasitic infections will be a cheaper and effective alternative to control parasitic infection for long time and improve animal production. PMID:27047140

[Prevalence of microsporidia and other intestinal parasites in patients with HIV infection, Bogota, 2001].

PubMed

Flórez, Astrid Carolina; García, Dabeiba Adriana; Moncada, Ligia; Beltrán, Mauricio

2003-09-01

Opportunistic intestinal parasites are a common cause of diarrhea in HIV-infected patients. To determine the prevalence of microsporidia and other opportunistic parasites infecting HIV patients in Bogotá, Colombia, 115 patients were examined for these infections during the year 2001. The institution and the sample percent from each are as follows: Santa Clara Hospital, 33.0%; San Pedro Claver, 20.0%; Simón Bolívar Hospital, 14.8%; San José Hospital, 13.9%; Central de la Policía Hospital, 6.1%; Compensar, 5.2%; Colombian League against AIDS, 2.6%; San Ignacio Hospital, 2.6%, and the Military Hospital, 1.7%. The average patient age was 36 years, with a range from 18 to 71 years. Patients with complaint of gastrointestinal symptoms were asked to provide two consecutive stool samples. The samples were concentrated in formalin-ether and examined microscopically for intestinal coccidian parasites by direct wet slide mounts. The prevalence of intestinal opportunistic parasites was 10.4% for Cryptosporidium sp. Initially, 29% of the samples were found to be positive for microsporidian spores using a modified Ziehl Neelsen chromotrope stain, but only 3.5% of them were confirmed as positive when a calcofluor/Gram chromotrope stain was used. The general prevalence of intestinal parasites was 59.1%. The most frequently found pathogens were Blastocystis hominis, 25.2%, and Entamoeba histolytica, 13%. In other studies with HIV patients in Colombia, lower prevalences of Cryptosporidium sp. infection were observed.

Gastrointestinal parasitic infection in diverse species of domestic ruminants inhabiting tribal rural areas of southern Rajasthan, India.

PubMed

Choubisa, S L; Jaroli, V J

2013-10-01

A total of 415 adult domesticated ruminants, 130 cattle (Bos taurus), 108 buffaloes (Bubalus bubalis), 94 goats (Capra hircus) and 83 sheep (Ovis aries) inhabiting tribal rural areas of southern Rajasthan, India were investigated for evidence of gastrointestinal protozoan and helminthic infections. In southern Rajasthan humid ecosystem is predominant and has number of perennial freshwater bodies. Fresh faecal samples of these animals were examined microscopically by direct wet smear with saline and 1 % Lugol's iodine and formalin ether concentration. Of these 296 (71.32 %) were found to be infected with different species of gastrointestinal parasites. The highest (93.84 %) prevalence of these parasitic infections was found in cattle followed by goats (82.97 %), sheep (55.42 %) and buffaloes (46.29 %). Except cattle no other ruminants revealed protozoan infection. A total 8 species of gastrointestinal parasites were encountered. Among these parasites Fasciola hepatica was the commonest (15.18 %) followed by Haemonchus contortus (11.32 %), Ancylostoma duodenale (10.36 %), Trichuris trichiura (9.15 %), Amphistome species (7.95 %), Moniezia expansa (6.98 %), Strongyloides stercoralis (4.57 %) and Balantidium coli (3.37 %). The prevalence rate of these parasitic infections also varied seasonally. The highest prevalence rate was found in rainy season (84.21 %) followed by winter (73.9 %) and summer (52.8 %). The possible causes for variation in prevalence of parasitic infections are also discussed.

A simple prediction score for developing a hospital-acquired infection after acute ischemic stroke.

PubMed

Friedant, Adam J; Gouse, Brittany M; Boehme, Amelia K; Siegler, James E; Albright, Karen C; Monlezun, Dominique J; George, Alexander J; Beasley, Timothy Mark; Martin-Schild, Sheryl

2015-03-01

Hospital-acquired infections (HAIs) are a major cause of morbidity and mortality in acute ischemic stroke patients. Although prior scoring systems have been developed to predict pneumonia in ischemic stroke patients, these scores were not designed to predict other infections. We sought to develop a simple scoring system for any HAI. Patients admitted to our stroke center (July 2008-June 2012) were retrospectively assessed. Patients were excluded if they had an in-hospital stroke, unknown time from symptom onset, or delay from symptom onset to hospital arrival greater than 48 hours. Infections were diagnosed via clinical, laboratory, and imaging modalities using standard definitions. A scoring system was created to predict infections based on baseline patient characteristics. Of 568 patients, 84 (14.8%) developed an infection during their stays. Patients who developed infection were older (73 versus 64, P < .0001), more frequently diabetic (43.9% versus 29.1%, P = .0077), and had more severe strokes on admission (National Institutes of Health Stroke Scale [NIHSS] score 12 versus 5, P < .0001). Ranging from 0 to 7, the overall infection score consists of age 70 years or more (1 point), history of diabetes (1 point), and NIHSS score (0-4 conferred 0 points, 5-15 conferred 3 points, >15 conferred 5 points). Patients with an infection score of 4 or more were at 5 times greater odds of developing an infection (odds ratio, 5.67; 95% confidence interval, 3.28-9.81; P < .0001). In our sample, clinical, laboratory, and imaging information available at admission identified patients at risk for infections during their acute hospitalizations. If validated in other populations, this score could assist providers in predicting infections after ischemic stroke. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Short-term parasite-infection alters already the biomass, activity and functional diversity of soil microbial communities

PubMed Central

Li, Jun-Min; Jin, Ze-Xin; Hagedorn, Frank; Li, Mai-He

2014-01-01

Native parasitic plants may be used to infect and control invasive plants. We established microcosms with invasive Mikania micrantha and native Coix lacryma-jobi growing in mixture on native soils, with M. micrantha being infected by parasitic Cuscuta campestris at four intensity levels for seven weeks to estimate the top-down effects of plant parasitism on the biomass and functional diversity of soil microbial communities. Parasitism significantly decreased root biomass and altered soil microbial communities. Soil microbial biomass decreased, but soil respiration increased at the two higher infection levels, indicating a strong stimulation of soil microbial metabolic activity (+180%). Moreover, a Biolog assay showed that the infection resulted in a significant change in the functional diversity indices of soil microbial communities. Pearson correlation analysis indicated that microbial biomass declined significantly with decreasing root biomass, particularly of the invasive M. micrantha. Also, the functional diversity indices of soil microbial communities were positively correlated with soil microbial biomass. Therefore, the negative effects on the biomass, activity and functional diversity of soil microbial community by the seven week long plant parasitism was very likely caused by decreased root biomass and root exudation of the invasive M. micrantha. PMID:25367357

Short-term parasite-infection alters already the biomass, activity and functional diversity of soil microbial communities

NASA Astrophysics Data System (ADS)

Li, Jun-Min; Jin, Ze-Xin; Hagedorn, Frank; Li, Mai-He

2014-11-01

Native parasitic plants may be used to infect and control invasive plants. We established microcosms with invasive Mikania micrantha and native Coix lacryma-jobi growing in mixture on native soils, with M. micrantha being infected by parasitic Cuscuta campestris at four intensity levels for seven weeks to estimate the top-down effects of plant parasitism on the biomass and functional diversity of soil microbial communities. Parasitism significantly decreased root biomass and altered soil microbial communities. Soil microbial biomass decreased, but soil respiration increased at the two higher infection levels, indicating a strong stimulation of soil microbial metabolic activity (+180%). Moreover, a Biolog assay showed that the infection resulted in a significant change in the functional diversity indices of soil microbial communities. Pearson correlation analysis indicated that microbial biomass declined significantly with decreasing root biomass, particularly of the invasive M. micrantha. Also, the functional diversity indices of soil microbial communities were positively correlated with soil microbial biomass. Therefore, the negative effects on the biomass, activity and functional diversity of soil microbial community by the seven week long plant parasitism was very likely caused by decreased root biomass and root exudation of the invasive M. micrantha.

Parasites and a host's sense of smell: reduced chemosensory performance of fathead minnows (Pimephales promelas) infected with a monogenean parasite.

PubMed

Lari, Ebrahim; Goater, Cameron P; Cone, David K; Pyle, Greg G

2017-05-01

Parasites residing within the central nervous system of their hosts have the potential to reduce various components of host performance, but such effects are rarely evaluated. We assessed the olfactory acuity of fathead minnows (Pimephales promelas) infected experimentally with the monogenean Dactylogyrus olfactorius, the adults of which live within the host's olfactory chambers. Olfactory acuity was compared between infected and uninfected hosts by assessing electro-olfactography (EOG) neural responses to chemical stimuli that indicate the presence of food (L-alanine) or the presence of conspecifics (taurocholic acid). We also compared differences in gross morphology of the olfactory epithelium in infected and uninfected minnows. Differences in EOG responses between infected and uninfected minnows to both cue types were non-significant at 30 days post-exposure. By days 60 and 90, coincident with a two times increase in parasite intensity in the olfactory chambers, the EOG responses of infected minnows were 70-90% lower than controls. When infected fish were treated with a parasiticide (Prazipro), olfactory acuity returned to control levels by day 7 post-treatment. The observed reduction in olfactory acuity is best explained by the reduced density of cilia covering the olfactory chambers of infected fish, or by the concomitant increase in the density of mucous cells that cover the olfactory chambers. These morphological changes are likely due to the direct effects of attachment and feeding by individual worms or by indirect effects associated with host responses. Our results show that infection of a commonly occurring monogenean in fathead minnows reduces olfactory acuity. Parasite-induced interference with olfactory performance may reduce a fish's ability to detect, or respond to, chemical cues originating from food, predators, competitors or mates. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

The Host Response in Patients with Sepsis Developing Intensive Care Unit-acquired Secondary Infections.

PubMed

van Vught, Lonneke A; Wiewel, Maryse A; Hoogendijk, Arie J; Frencken, Jos F; Scicluna, Brendon P; Klein Klouwenberg, Peter M C; Zwinderman, Aeilko H; Lutter, Rene; Horn, Janneke; Schultz, Marcus J; Bonten, Marc M J; Cremer, Olaf L; van der Poll, Tom

2017-08-15

Sepsis can be complicated by secondary infections. We explored the possibility that patients with sepsis developing a secondary infection while in the intensive care unit (ICU) display sustained inflammatory, vascular, and procoagulant responses. To compare systemic proinflammatory host responses in patients with sepsis who acquire a new infection with those who do not. Consecutive patients with sepsis with a length of ICU stay greater than 48 hours were prospectively analyzed for the development of ICU-acquired infections. Twenty host response biomarkers reflective of key pathways implicated in sepsis pathogenesis were measured during the first 4 days after ICU admission and at the day of an ICU-acquired infection or noninfectious complication. Of 1,237 admissions for sepsis (1,089 patients), 178 (14.4%) admissions were complicated by ICU-acquired infections (at Day 10 [6-13], median with interquartile range). Patients who developed a secondary infection showed higher disease severity scores and higher mortality up to 1 year than those who did not. Analyses of biomarkers in patients who later went on to develop secondary infections revealed a more dysregulated host response during the first 4 days after admission, as reflected by enhanced inflammation, stronger endothelial cell activation, a more disturbed vascular integrity, and evidence for enhanced coagulation activation. Host response reactions were similar at the time of ICU-acquired infectious or noninfectious complications. Patients with sepsis who developed an ICU-acquired infection showed a more dysregulated proinflammatory and vascular host response during the first 4 days of ICU admission than those who did not develop a secondary infection.

Prevalence of intestinal parasites in Isfahan city, central Iran, 2014.

PubMed

Jafari, Rasool; Sharifi, Forough; Bagherpour, Bahram; Safari, Marzieh

2016-09-01

Intestinal parasites are important enteric pathogens. Poverty, low quality of food and water supply and poor sanitation systems are the important factors associated with intestinal parasitic infections. These kinds of infections can be a good index for hygienic and sanitation status of the society. This study aimed to determine the prevalence of intestinal parasitic infections among humans referred to Dr. Sharifi Clinical Laboratory, Isfahan, Iran, 2014. In this cross sectional study, 652 fecal samples (286 males and 366 females) from humans who had stool examination test from January to August 2014 were chosen. Microscopic examination for parasitic infections has been carried out using wet mount method. Indistinguishable samples underwent trichrome staining method for accurate identification of protozoa. Intestinal parasitic infections were observed in 68 (10.42 %) out of 652 studied humans. Forty eight Blastocystis hominis (7.36 %), thirteen Endolimax nana (1.99 %), nine Giardia lamblia (1.38 %), five Entamoeba coli (0.76 %), four Chilomastix mesnili (0.61 %) and two Iodamoeba butschlii (0.15 %) were the observed protozoa in the studied population. B. hominis, E. nana and C. mesnili were found to be significantly more prevalent in people with loose stool specimen. Considering the helminthic infections, only one case (0.15 %) that was excreted Taenia saginata proglottids has been documented among 652 studied humans. Based on the findings of the present study intestinal parasitic infections in Isfahan city has been dramatically decreased over the past years and shows a good hygienic and sanitation status of the city.

Parasite Sequestration in Plasmodium falciparum Malaria: Spleen and Antibody Modulation of Cytoadherence of Infected Erythrocytes

NASA Astrophysics Data System (ADS)

David, Peter H.; Hommel, Marcel; Miller, Louis H.; Udeinya, Iroka J.; Oligino, Lynette D.

1983-08-01

Sequestration, the adherence of infected erythrocytes containing late developmental stages of the parasite (trophozoites and schizonts) to the endothelium of capillaries and venules, is characteristic of Plasmodium falciparum infections. We have studied two host factors, the spleen and antibody, that influence sequestration of P. falciparum in the squirrel monkey. Sequestration of trophozoite/schizont-infected erythrocytes that occurs in intact animals is reduced in splenectomized animals; in vitro, when infected blood is incubated with monolayers of human melanoma cells, trophozoite/schizont-infected erythrocytes from intact animals but not from splenectomized animals bind to the melanoma cells. The switch in cytoadherence characteristics of the infected erythrocytes from nonbinding to binding occurs with a cloned parasite. Immune serum can inhibit and reverse in vitro binding to melanoma cells of infected erythrocytes from intact animals. Similarly, antibody can reverse in vivo sequestration as shown by the appearance of trophozoite/schizont-infected erythrocytes in the peripheral blood of an intact animal after inoculation with immune serum. These results indicate that the spleen modulates the expression of parasite alterations of the infected erythrocyte membrane responsible for sequestration and suggest that the prevention and reversal of sequestration could be one of the effector mechanisms involved in antibody-mediated protection against P. falciparum malaria.

Transmission of molecularly undetectable circulating parasite clones leads to high infection complexity in mosquitoes post feeding.

PubMed

Grignard, Lynn; Gonçalves, Bronner P; Early, Angela M; Daniels, Rachel F; Tiono, Alfred B; Guelbéogo, Wamdaogo M; Ouédraogo, Alphonse; van Veen, Elke M; Lanke, Kjerstin; Diarra, Amidou; Nebie, Issa; Sirima, Sodiomon B; Targett, Geoff A; Volkman, Sarah K; Neafsey, Daniel E; Wirth, Dyann F; Bousema, Teun; Drakeley, Chris

2018-05-05

Plasmodium falciparum malaria infections often comprise multiple distinct parasite clones. Few datasets have directly assessed infection complexity in humans and mosquitoes they infect. Examining parasites using molecular tools may provide insights into the selective transmissibility of isolates. Using capillary electrophoresis genotyping and next generation amplicon sequencing, we analysed complexity of parasite infections in human blood and in the midguts of mosquitoes that became infected in membrane feeding experiments using the same blood material in two West African settings. Median numbers of clones in humans and mosquitoes were higher in samples from Burkina Faso (4.5, interquartile range 2-8 for humans; and 2, interquartile range 1-3 for mosquitoes) than in The Gambia (2, interquartile range 1-3 and 1, interquartile range 1-3, for humans and mosquitoes, respectively). Whilst the median number of clones was commonly higher in human blood samples, not all transmitted alleles were detectable in the human peripheral blood. In both study sample sets, additional parasite alleles were identified in mosquitoes compared with the matched human samples (10-88.9% of all clones/feeding assay, n = 73 feeding assays). The results are likely due to preferential amplification of the most abundant clones in peripheral blood but confirm the presence of low density clones that produce transmissible sexual stage parasites. Copyright © 2018. Published by Elsevier Ltd.

Active retinitis in an infant with postnatally acquired cytomegalovirus infection.

PubMed

Piersigilli, F; Catena, G; De Gasperis, M R; Lozzi, S; Auriti, C

2012-07-01

Congenital cytomegalovirus (CMV) is frequently associated with active retinitis. In contrast, in the immunocompetent neonate with postnatally acquired CMV infection retinitis is rarely present and usually does not progress. We describe the case of an infant with postnatal CMV infection and active retinitis diagnosed at 20 days of life. Owing to the rapid progression of the retinitis, therapy with intravenous ganciclovir was performed, with prompt regression of the retinitis. Therapy was then continued with oral valganciclovir for one further week. Although very unusual, CMV retinitis has to be taken into consideration in neonates with early postnatally acquired CMV infection, as an early diagnosis and treatment may be crucial to avoid visual impairment.

Parasitic infections on the shore of Lake Victoria (East Africa) detected by Mini-FLOTAC and standard techniques.

PubMed

Barda, Beatrice; Ianniello, Davide; Zepheryne, Henry; Rinaldi, Laura; Cringoli, Giuseppe; Burioni, Roberto; Albonico, Marco

2014-09-01

Helminths and protozoa infections pose a great burden especially in developing countries, due to morbidity caused by both acute and chronic infection. The aim of our survey was to analyze the intestinal parasitic burden in communities from Mwanza region, Tanzania. Subjects (n=251) from four villages on the South of Lake Victoria have been analyzed for intestinal parasites with direct smear (DS), formol-ether concentration method (FECM) and the newly developed Mini-FLOTAC technique; urinary schistosomiasis was also assessed in a subsample (n=151); symptoms were registered and correlation between clinic and infections was calculated by chi-squared test and logistical regression. Out of the subjects screened for intestinal and for urinary parasites, 87% (218/251) were found positive for any infection, 69% (174/251) carried a helminthic and 67% (167/251) a protozoan infection, almost half of them had a double or triple infection. The most common helminths were hookworms, followed by Schistosoma mansoni and Schistosoma haematobium. Among protozoa, the most common was Entamoeba coli followed by Entamoeba histolytica/dispar and Giardia intestinalis. Mini-FLOTAC detected a number of helminth infections (61.7%) higher than FECM (38.6%) and DS (17.9%). Some positive associations with abdominal symptoms were found and previous treatment was negatively correlated with infection. Despite the limited size of the examined population the current study indicates a high prevalence of intestinal parasitic infection in Bukumbi area, Tanzania, and Mini-FLOTAC showed to be a promising diagnostic tool for helminth infections. This high parasitic burden calls for starting a regular deworming programme and other preventive interventions in schools and in the community. Copyright © 2014 Elsevier B.V. All rights reserved.

Laboratory-associated infections and biosafety.

PubMed Central

Sewell, D L

1995-01-01

An estimated 500,000 laboratory workers in the United States are at risk of exposure to infectious agents that cause disease ranging from inapparent to life-threatening infections, but the precise risk to a given worker unknown. The emergence of human immunodeficiency virus and hantavirus, the continuing problem of hepatitis B virus, and the reemergence of Mycobacterium tuberculosis have renewed interest in biosafety for the employees of laboratories and health care facilities. This review examines the history, the causes, and the methods for prevention of laboratory-associated infections. The initial step in a biosafety program is the assessment of risk to the employee. Risk assessment guidelines include the pathogenicity of the infectious agent, the method of transmission, worker-related risk factors, the source and route of infection, and the design of the laboratory facility. Strategies for the prevention and management of laboratory-associated infections are based on the containment of the infectious agent by physical separation from the laboratory worker and the environment, employee education about the occupational risks, and availability of an employee health program. Adherence to the biosafety guidelines mandated or proposed by various governmental and accrediting agencies reduces the risk of an occupational exposure to infectious agents handled in the workplace. PMID:7553572

History of Medical Parasitology and Parasitic Infections in Iran.

PubMed

Edrissian, Gholamhossein; Rokni, Mohammad Bagher; Mohebali, Mehdi; Nateghpour, Mehdi; Mowlavi, Gholamreza; Bahadori, Moslem

2016-08-01

Parasites and parasitic diseases have been prevalent in Iran according to Iranian ancient scholars and physicians' inscriptions dating back to 865-1496. Some protozoan diseases such as malaria and cutaneous leishmaniasis have been introduced by clinical manifestations and helminthic infections by size and morphology of the worms. Scientific studies of Parasitology started in Iran from 1833, first by foreign physicians and continued from 1909 by Iranian researchers. The pioneer medical parasitologists of Iran were Dr N. Ansari and Dr. Sh. Mofidi who established the Department of Medical Parasitology in the School of Medicine, University of Tehran, 1939. Afterward, a considerable number of researchers and professors of parasitology have been active in training and research works in the fields of medical parasitology throughout the entire nation. At present, some significant parasitic diseases such as bilharsiasis and dracunculiasis are more or less eradicated and malaria is in the elimination phase. The prevalence of most helminthic infections has considerably decreased. Most of the departments of medical Parasitology in Iran are active in training MD, MSPH and PhD students. The Iranian Society of Parasitology established in 1994 is active with many eligible members and its creditable publication, the Iranian Journal of Parasitology, published seasonally since 2006. From 1833, when the scientific studies of Parasitology have started in Iran up to 2013, many researchers have been done on various fields of medical Parasitology and parasitic diseases in Iran and 2517 papers in English and 1890 papers in Persian have been published in national and international scientific journals. In addition, more than 420 books related in the field of medical parasitology field have been published in Persian language.

Effects of supplemental feeding on gastrointestinal parasite infection in Rocky Mountain Elk (Cervus elaphus)

USGS Publications Warehouse

Hines, Alicia M.; Ezenwa, Vanessa O.; Cross, Paul C.; Rogerson, Jared D.

2007-01-01

The effects of management practices on the spread and impact of parasites and infectious diseases in wildlife and domestic animals are of increasing concern worldwide, particularly in cases where management of wild species can influence disease spill-over into domestic animals. In the Greater Yellowstone Ecosystem, USA, winter supplemental feeding of Rocky Mountain elk (Cervus elaphus) may enhance parasite and disease transmission by aggregating elk on feedgrounds. In this study, we tested the effect of supplemental feeding on gastrointestinal parasite infection in elk by comparing fecal egg/oocyst counts of fed and unfed elk. We collected fecal samples from fed and unfed elk at feedground and control sites from January to April 2006, and screened all samples for parasites. Six different parasite types were identified, and 48.7% of samples were infected with at least one parasite. Gastrointenstinal (GI) nematodes (Nematoda: Strongylida), Trichuris spp., and coccidia were the most common parasites observed. For all three of these parasites, fecal egg/oocyst counts increased from January to April. Supplementally fed elk had significantly higher GI nematode egg counts than unfed elk in January and February, but significantly lower counts in April. These patterns suggest that supplemental feeding may both increase exposure and decrease susceptibility of elk to GI nematodes, resulting in differences in temporal patterns of egg shedding between fed and unfed elk.

Zoonotic enteric parasites transmitted from dogs in Egypt with special concern to Toxocara canis infection

PubMed Central

Awadallah, Maysa A. I.; Salem, Lobna M. A.

2015-01-01

Aim: This work aimed to study the role played by dogs in transmitting zoonotic enteric parasites to humans in Egypt and to analyze the risk factors associated with the occurrence of such infection in dogs. Serodiagnosis of anti-Toxocara immunoglobulin G (IgG) antibodies among human beings as well as analyzing risk factors predispose to Toxocara canis infection in human beings are another objectives of this study. Materials and Methods: From June to December 2013, a total of 130 fecal samples from 4 dog populations (Military, nomadic and domiciled dogs from rural and high standard districts) and 150 stool samples of 6 occupational groups were examined for the presence of enteric parasitic infection. Moreover, 150 serum samples were collected from humans from whom stool samples were collected and examined for the presence of anti-T. canis antibodies. Results: Enteric parasites were detected in 30% of fecal samples from 4 dog populations in Egypt. High infectivity had been reported in nomadic dogs (63.33%) (Crude odds ratios [COR]=67.36, 95% confidence interval [CI]=8.09-560.8, p<0.000), followed by domiciled dogs from rural areas (40%) (COR=26, 95% CI=3.14-215.54, p=0.003), domiciled dogs from high standard areas (23.33%) (COR=11.87, 95% CI=1.37-102.69, p=0.025) and military dogs (2.5%). Twelve species of enteric parasites were identified, Ancylostomatidae (6.15%), T. canis and Cryptosporidium spp. (5.38%, each), Heterophyes spp. (3.85%), Toxocara leonina and Blastocystis spp. (3.07%), Taenidae eggs (2.31%), Hymenolepis diminuta (1.54%) and Entamoeba canis, Cyclospora cayetanensis, and Paragonimus spp. (0.77%, each). Univariate logestic regression revealed significant association of age (COR=4.73, 95% CI=2.13-10.53, p<0.000), gender (COR=2.63, 95% CI=1.22-5.68, p<0.014), housing system (COR=5.10, 95% CI=2.04-12.75), p<0.000) with enteric parasitic infection in dogs. However, breeds (COR=6.91, 95% CI=0.88-54.52, p=0.067) and type of feeding (COR ranged from 3.5 to 7

Parasitic diseases of zoonotic importance in humans of northeast India, with special reference to ocular involvement.

PubMed

Das, Dipankar; Islam, Saidul; Bhattacharjee, Harsha; Deka, Angshuman; Yambem, Dinakumar; Tahiliani, Prerana Sushil; Deka, Panna; Bhattacharyya, Pankaj; Deka, Satyen; Das, Kalyan; Bharali, Gayatri; Deka, Apurba; Paul, Rajashree

2014-01-01

Parasitic zoonotic diseases are prevalent in India, including the northeastern states. Proper epidemiological data are lacking from this part of the country on zoonotic parasitic diseases, and newer diseases are emerging in the current scenario. Systemic manifestation of such diseases as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. The incidence of acquired toxoplasmal infection is showing an increasing trend in association with acquired immunodeficiency syndrome. Among the ocular parasitic diseases, toxoplasmosis, cysticercosis, toxocariasis, dirofilariasis, gnathostomiasis, hydatidosis, amebiasis, giardiasis, etc, are the real problems that are seen in this subset of the population. Therefore, proper coordination between various medical specialities, including veterinary science and other governing bodies, is needed for better and more effective strategic planning to control zoonoses.

Human Parasitic Diseases in Bulgaria in Between 2013-2014

PubMed Central

Rainova, Iskra; Harizanov, Rumen; Kaftandjiev, Iskren; Tsvetkova, Nina; Mikov, Ognyan; Kaneva, Eleonora

2018-01-01

Background: In Bulgaria, more than 20 autochthonous human parasitic infections have been described and some of them are widespread. Over 50 imported protozoan and helminthic infections represent diagnostic and therapeutic challenges and pose epidemiological risks due to the possibility of local transmission. Aims: To establish the distribution of autochthonous and imported parasitic diseases among the population of the country over a 2-year period (2013-2014) and to evaluate their significance in the public health system. Study Design: Cross sectional study. Methods: We used the annual reports by regional health inspectorates and data from the National Reference Laboratory at the National Centre of Infectious and Parasitic Diseases on all individuals infected with parasitic diseases in the country. Prevalence was calculated for parasitic diseases with few or absent clinical manifestations (oligosymptomatic or asymptomatic infections). Incidence per 100.000 was calculated for diseases with an overt clinical picture or those that required hospitalisation and specialised medical interventions (e.g. surgery). Results: During the research period, parasitological studies were conducted on 1441.244 persons, and parasitic infections were diagnosed in 22.039 individuals. Distribution of various parasitic pathogens among the population displayed statistically significant differences in prevalence for some intestinal parasites (enterobiasis 0.81%, giardiasis 0.34% and blastocystosis 0.22%). For certain zoonotic diseases such as cystic echinococcosis (average incidence of 3.99 per 100.000) and trichinellosis (average incidence of 0.8 per 100.000), the incidence exceeds several times the annual incidence recorded in the European Union. Conclusion: Parasitic diseases still pose a substantial problem with social and medical impacts on the residents of our country. Improved efficiency regarding autochthonous and imported parasitic diseases is essential in providing the public

Efficacy of garlic based treatments against monogenean parasites infecting the guppy (Poecilia reticulata (Peters)).

PubMed

Fridman, S; Sinai, T; Zilberg, D

2014-06-16

Monogenean infections of commercially farmed fishes are responsible for significant economic losses. Garlic (Allium sativum) is a well-known spice which also possesses anti-microbial and anti-parasitical properties. The current work aimed to test the efficacy of garlic-based treatments against infection with monogenean sp. in the guppy (Poecilia reticulata). Clipped sections of tail fins of guppies heavily infected with Gyrodactylus turnbulli were exposed to aqueous garlic extract (7.5 to 30 mL L(-1)) and visually observed under a dissecting microscope. Results revealed that exposure to garlic caused detachment of parasite and cessation of movement indicating death. A positive correlation was seen between garlic concentration and time to detachment and death of parasites, which, at the highest concentration of 30 mL L(-1), occurred at 4.1 and 8.6 min, respectively. Bathing in aqueous garlic extract (7.5 and 12.5 mL L(-1)) was tested in guppies infected with G. turnbulli. Prior acute toxicity tests revealed the maximum tolerance levels of guppies to garlic extract to be 12.5 mL L(-1) for 1h. Bathing of infected fish in garlic extract (7.5 and 12.5 mL L(-1)) significantly (p<0.05) reduced infection prevalence and intensity as compared to the control. Oral treatments using dry garlic powder-supplemented diet were tested on guppies infected with G. turnbulli and Dactylogyrus sp. Fish were fed with food containing 10% and 20% dry garlic powder for 14 days. Groups fed with garlic supplemented diets showed significantly reduced (p<0.05) mean prevalence and mean intensity of parasites as compared to the control. Dietary application of garlic did not appear to affect palatability. Fresh crushed garlic was added at a level of 1 gL(-1) and applied as an indefinite bath for 14 days. This treatment was seen to significantly reduce (p<0.05) parasite prevalence and mean intensity as compared to the control. Histopathology revealed elevated muscular dystrophy in the 20% garlic

Acquired toxoplasmosis of a submandibular lymph node in a 13-year-old boy: case report.

PubMed

Azaz, B; Milhem, I; Hasson, O; Kirsch, G

1994-01-01

Toxoplasmosis is a parasitic infection divided into congenital and acquired forms. In the latter form, malaise, fatigue, and lymphadenopathy are commonly found, and submandibular lymphadenopathy is sometimes a manifestation. In children, cervical lymph nodes usually are affected. This is a case of a 13-year-old boy suffering from acquired toxoplasmosis, in which submandibular lymphadenopathy was the only clinical sign of the disease. Meticulous history taking, clinical examination, and specific serological tests should be performed in these cases. Positive serological results will confirm toxoplasmosis infections. Conservative treatment must be attempted initially.

Parasitic nematodes modulate PIN-mediated auxin transport to facilitate infection.

PubMed

Grunewald, Wim; Cannoot, Bernard; Friml, Jirí; Gheysen, Godelieve

2009-01-01

Plant-parasitic nematodes are destructive plant pathogens that cause significant yield losses. They induce highly specialized feeding sites (NFS) in infected plant roots from which they withdraw nutrients. In order to establish these NFS, it is thought that the nematodes manipulate the molecular and physiological pathways of their hosts. Evidence is accumulating that the plant signalling molecule auxin is involved in the initiation and development of the feeding sites of sedentary plant-parasitic nematodes. Intercellular transport of auxin is essential for various aspects of plant growth and development. Here, we analysed the spatial and temporal expression of PIN auxin transporters during the early events of NFS establishment using promoter-GUS/GFP fusion lines. Additionally, single and double pin mutants were used in infection studies to analyse the role of the different PIN proteins during cyst nematode infection. Based on our results, we postulate a model in which PIN1-mediated auxin transport is needed to deliver auxin to the initial syncytial cell, whereas PIN3 and PIN4 distribute the accumulated auxin laterally and are involved in the radial expansion of the NFS. Our data demonstrate that cyst nematodes are able to hijack the auxin distribution network in order to facilitate the infection process.

Parasites in the city: degree of urbanization predicts poxvirus and coccidian infections in house finches (Haemorhous mexicanus).

PubMed

Giraudeau, Mathieu; Mousel, Melanie; Earl, Stevan; McGraw, Kevin

2014-01-01

Urbanization can strongly impact the physiology, behavior, and fitness of animals. Conditions in cities may also promote the transmission and success of animal parasites and pathogens. However, to date, no studies have examined variation in the prevalence or severity of several distinct pathogens/parasites along a gradient of urbanization in animals or if these infections increase physiological stress in urban populations. Here, we measured the prevalence and severity of infection with intestinal coccidians (Isospora sp.) and the canarypox virus (Avipoxvirus) along an urban-to-rural gradient in wild male house finches (Haemorhous mexicanus). In addition, we quantified an important stress indicator in animals (oxidative stress) and several axes of urbanization, including human population density and land-use patterns within a 1 km radius of each trapping site. Prevalence of poxvirus infection and severity of coccidial infection were significantly associated with the degree of urbanization, with an increase of infection in more urban areas. The degrees of infection by the two parasites were not correlated along the urban-rural gradient. Finally, levels of oxidative damage in plasma were not associated with infection or with urbanization metrics. These results indicate that the physical presence of humans in cities and the associated altered urban landscape characteristics are associated with increased infections with both a virus and a gastrointestinal parasite in this common songbird resident of North American cities. Though we failed to find elevations in urban- or parasite/pathogen-mediated oxidative stress, humans may facilitate infections in these birds via bird feeders (i.e. horizontal disease transmission due to unsanitary surfaces and/or elevations in host population densities) and/or via elevations in other forms of physiological stress (e.g. corticosterone, nutritional).

SEASONAL AND DEMOGRAPHIC FACTORS INFLUENCING GASTROINTESTINAL PARASITISM IN UNGULATES OF ETOSHA NATIONAL PARK

PubMed Central

Turner, Wendy C.; Getz, Wayne M.

2011-01-01

Host-parasite dynamics can be strongly affected by seasonality and age-related host immune responses. We investigated how observed variation in the prevalence and intensity of parasite egg or oocyst shedding in four co-occurring ungulate species may reflect underlying seasonal variation in transmission and host immunity. This study was conducted July 2005–October 2006 in Etosha National Park, Namibia, using indices of parasitism recorded from 1,022 fecal samples collected from plains zebra (Equus quagga), springbok (Antidorcas marsupialis), blue wildebeest (Connochaetes taurinus), and gemsbok (Oryx gazella). The presence and intensity of strongyle nematodes, Strongyloides spp. and Eimeria spp. parasites, were strongly seasonal for most host-parasite combinations, with more hosts infected in the wet season than the dry season. Strongyle intensity in zebra was significantly lower in juveniles than adults, and in springbok hosts, Eimeria spp. intensity was significantly greater in juveniles than adults. These results provide evidence that acquired immunity is less protective against strongyle nematodes than Eimeria spp. infections. The seasonal patterns in parasitism further indicate that the long dry season may limit development and survival of parasite stages in the environment and, as a result, host contact and parasite transmission. PMID:20966262

[Where do the parasites of man come from?].

PubMed

Combes, C

1990-01-01

The Hominids have come in contact, over the last few million years, with the infective stages of many parasites which had up to then evolved in non Primate hosts; this is because Hominids have occupied multiple environments and acquired diversified behaviour. The high number of these lateral transfers explains the multiplicity of current human parasitic diseases whereas their youth on an evolutionary scale accounts for the seriousness of most of these diseases. The basic questions arising from the exceptional opportunities offered to parasites by the evolution of the human lineage concern: the precise role played by human behaviour, the mechanisms of alterations in specificity, the identity of the original host phyla, the dynamic and genetic consequences for parasites, the relationship with the evolutionary history of the ancestors of Homo sapiens sapiens; for instance, it is suggested that man's mastery of fire, allowing him to cook his food, dramatically reduced his contamination by certain parasites and that this contributed to the subsequent success of Hominids.

Pork as a source of transmission of Toxoplasma gondii to humans: a parasite burden study in pig tissues after infection with different strains of Toxoplasma gondii as a function of time and different parasite stages.

PubMed

Gisbert Algaba, Ignacio; Verhaegen, Bavo; Jennes, Malgorzata; Rahman, Mizanur; Coucke, Wim; Cox, Eric; Dorny, Pierre; Dierick, Katelijne; De Craeye, Stéphane

2018-06-01

Toxoplasma gondii is an ubiquitous apicomplexan parasite which can infect any warm-blooded animal including humans. Humans and carnivores/omnivores can also become infected by consumption of raw or undercooked infected meat containing muscle cysts. This route of transmission is considered to account for at least 30% of human toxoplasmosis cases. To better assess the role of pork as a source of infection for humans, the parasite burden resulting from experimental infection with different parasite stages and different strains of T. gondii during the acute and chronic phases was studied. The parasite burden in different tissues was measured with a ISO 17025 validated Magnetic Capture-quantitative PCR. A high burden of infection was found in heart and lungs during the acute phase of infection and heart and brain were identified as the most parasitised tissues during the chronic phase of infection, independent of the parasite stage and the strain used. Remarkably, a higher parasite burden was measured in different tissues following infection with oocysts of a type II strain compared with a tissue cyst infection with three strains of either type II or a type I/II. However, these results could have been affected by the use of different strains and euthanasia time points. The parasite burden resulting from a tissue cyst infection was not significantly different between the two strains. Copyright © 2018 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

The role of social cognition in parasite and pathogen avoidance.

PubMed

Kavaliers, Martin; Choleris, Elena

2018-07-19

The acquisition and use of social information are integral to social behaviour and parasite/pathogen avoidance. This involves social cognition which encompasses mechanisms for acquiring, processing, retaining and acting on social information. Social cognition entails the acquisition of social information about others (i.e. social recognition) and from others (i.e. social learning). Social cognition involves assessing other individuals and their infection status and the pathogen and parasite threat they pose and deciding about when and how to interact with them. Social cognition provides a framework for examining pathogen and parasite avoidance behaviours and their associated neurobiological mechanisms. Here, we briefly consider the relationships between social cognition and olfactory-mediated pathogen and parasite avoidance behaviours. We briefly discuss aspects of (i) social recognition of actual and potentially infected individuals and the impact of parasite/pathogen threat on mate and social partner choice; (ii) the roles of 'out-groups' (strangers, unfamiliar individuals) and 'in-groups' (familiar individuals) in the expression of parasite/pathogen avoidance behaviours; (iii) individual and social learning, i.e. the utilization of the pathogen recognition and avoidance responses of others; and (iv) the neurobiological mechanisms, in particular the roles of the nonapeptide, oxytocin and steroid hormones (oestrogens) associated with social cognition and parasite/pathogen avoidance.This article is part of the Theo Murphy meeting issue 'Evolution of pathogen and parasite avoidance behaviours'. © 2018 The Author(s).

Parasites and personality in periwinkles (Littorina littorea): Infection status is associated with mean-level boldness but not repeatability.

PubMed

Seaman, Ben; Briffa, Mark

2015-06-01

We demonstrate the presence of animal personality in an inter-tidal gastropod, Littorina littorea, both in a sample of individuals infected by the trematode Cryptocotyle lingua and in an uninfected sample. On average infected individuals behaved more cautiously than individuals free of infection, but the parasite did not affect repeatability. Although the parasite is not associated with greater diversity of behaviour amongst infected individuals, infection might be associated with state-dependent personality differences between infected and non-infected individuals. Copyright © 2015. Published by Elsevier B.V.

Prevalence of intestinal parasitic infections and associated risk factors among students at Dona Berber primary school, Bahir Dar, Ethiopia.

PubMed

Hailegebriel, Tamirat

2017-05-23

Intestinal parasitic infections are still one of the major health concerns in developing countries. Monitoring of intestinal parasitic infection and associated risk factors are essential for intervention strategies. Therefore, the aim of this study was to assess the prevalence of intestinal parasitic infection and associated risk factors among students at Dona Berber primary school, Bahir Dar, Ethiopia. School based cross-sectional study was conducted among students at Dona Berber primary school from October 2015 to June 2016. Three hundred fifty nine students were involved in the study by providing stool specimens and detailed personal information. Students were selected by stratified and systematic random sampling method. Fresh stool samples were collected from each student and processed by formal-ether fecal concentration technique. Data were analyzed using SPSS version 20.0 statistical software and p value <0.05 were used as statistically significant. Among the 359 students participated in the study, 235 (65.5%) were infected by one or more intestinal parasites. The rates of single and double parasitic infections among students were 49.6% and 16.2%, respectively. The most prevalent parasite detected in the study was E. histolytica/dispar (24.5%) followed by hookworm (22.8%). Among the different variables assessed in the study, family size of 6 (AOR = 4.90; 95% CI, 2.03-11.83), irregularly shoe wearing habit (AOR = 2.85; 95% CI, 1.53-5.32) and unclean finger nail (AOR = 3.68; 95% CI, 1.87-7.26) were independently predict intestinal parasitic infections. Student drinking well water (AOR = 2.51; 95% CI, 2.30-4.86) and unclean finger nail (AOR = 4.42; 95% CI, 2.55-7.65) were strongly associated with E. histolytica/dispar infection. Likewise, irregular shoe wearing habit (AOR = 14.13; 95% CI, 7.06-28.29) was strongly associated with hookworm infections. High prevalence of intestinal parasitic infection among the study participants demands improvement of

NSR-seq transcriptional profiling enables identification of a gene signature of Plasmodium falciparum parasites infecting children.

PubMed

Vignali, Marissa; Armour, Christopher D; Chen, Jingyang; Morrison, Robert; Castle, John C; Biery, Matthew C; Bouzek, Heather; Moon, Wonjong; Babak, Tomas; Fried, Michal; Raymond, Christopher K; Duffy, Patrick E

2011-03-01

Malaria caused by Plasmodium falciparum results in approximately 1 million annual deaths worldwide, with young children and pregnant mothers at highest risk. Disease severity might be related to parasite virulence factors, but expression profiling studies of parasites to test this hypothesis have been hindered by extensive sequence variation in putative virulence genes and a preponderance of host RNA in clinical samples. We report here the application of RNA sequencing to clinical isolates of P. falciparum, using not-so-random (NSR) primers to successfully exclude human ribosomal RNA and globin transcripts and enrich for parasite transcripts. Using NSR-seq, we confirmed earlier microarray studies showing upregulation of a distinct subset of genes in parasites infecting pregnant women, including that encoding the well-established pregnancy malaria vaccine candidate var2csa. We also describe a subset of parasite transcripts that distinguished parasites infecting children from those infecting pregnant women and confirmed this observation using quantitative real-time PCR and mass spectrometry proteomic analyses. Based on their putative functional properties, we propose that these proteins could have a role in childhood malaria pathogenesis. Our study provides proof of principle that NSR-seq represents an approach that can be used to study clinical isolates of parasites causing severe malaria syndromes as well other blood-borne pathogens and blood-related diseases.

NSR-seq transcriptional profiling enables identification of a gene signature of Plasmodium falciparum parasites infecting children

PubMed Central

Vignali, Marissa; Armour, Christopher D.; Chen, Jingyang; Morrison, Robert; Castle, John C.; Biery, Matthew C.; Bouzek, Heather; Moon, Wonjong; Babak, Tomas; Fried, Michal; Raymond, Christopher K.; Duffy, Patrick E.

2011-01-01

Malaria caused by Plasmodium falciparum results in approximately 1 million annual deaths worldwide, with young children and pregnant mothers at highest risk. Disease severity might be related to parasite virulence factors, but expression profiling studies of parasites to test this hypothesis have been hindered by extensive sequence variation in putative virulence genes and a preponderance of host RNA in clinical samples. We report here the application of RNA sequencing to clinical isolates of P. falciparum, using not-so-random (NSR) primers to successfully exclude human ribosomal RNA and globin transcripts and enrich for parasite transcripts. Using NSR-seq, we confirmed earlier microarray studies showing upregulation of a distinct subset of genes in parasites infecting pregnant women, including that encoding the well-established pregnancy malaria vaccine candidate var2csa. We also describe a subset of parasite transcripts that distinguished parasites infecting children from those infecting pregnant women and confirmed this observation using quantitative real-time PCR and mass spectrometry proteomic analyses. Based on their putative functional properties, we propose that these proteins could have a role in childhood malaria pathogenesis. Our study provides proof of principle that NSR-seq represents an approach that can be used to study clinical isolates of parasites causing severe malaria syndromes as well other blood-borne pathogens and blood-related diseases. PMID:21317536

Infection with HIV and intestinal parasites among street dwellers in Gondar city, northwest Ethiopia.

PubMed

Moges, Feleke; Kebede, Yenew; Kassu, Afework; Degu, Getu; Tiruneh, Moges; Gedefaw, Molla

2006-12-01

In Ethiopia human immunodeficiency virus (HIV) infection is a major health and socioeconomic problem. Sex workers, youth, and mobile populations all show increasing prevalence of HIV. However, there is currently no information about the seroprevalence of HIV and the knowledge of HIV among street dwellers in the country. To fill this gap, 404 street dwellers residing in Gondar, northwest Ethiopia, were included in this cross-sectional study. Socio-demographic data, factors that prompted the subjects to become street dwellers, and their knowledge about HIV were all assessed using a structured questionnaire. Stool samples for diagnosis of intestinal parasites and venous blood for HIV antibody testing were collected and processed following standard procedures. Poverty-associated movement to urban areas in search of work was reported as a major factor that forced them to live in the streets, followed by divorce, family death, and addiction and peer pressure. One or more intestinal parasites were found in 67.6% of the street dwellers. Multiple parasitic infections were detected in 27.7%. The prevalence of HIV in the street dwellers was 6.9%. Fifty-nine (16.6%) participants responded that HIV can be transmitted by eating food together. Seventy-three (18%) believed an infected needle cannot transmit HIV, while 51 (12.6%) said HIV can be transmitted by hand shaking. One hundred ninety-two (47.5%) responded that antiretroviral therapy will not prolong the life of HIV-infected individuals. In summary, the prevalence of HIV and intestinal parasitic infection was quite high among street dwellers in Gondar. Therefore, strategies to control HIV and other infectious diseases should include this group, and regular mass deworming may help to reduce the burden of infection.

Parasites that cause problems in Malaysia: soil-transmitted helminths and malaria parasites.

PubMed

Singh, B; Cox-Singh, J

2001-12-01

Malaysia is a developing country with a range of parasitic infections. Indeed, soil-transmitted helminths and malaria parasites continue to have a significant impact on public health in Malaysia. In this article, the prevalence and distribution of these parasites, the problems associated with parasitic infections, the control measures taken to deal with these parasites and implications for the future will be discussed.

Prevalence and factors associated with intestinal parasitic infections among food handlers of Southern Ethiopia: cross sectional study.

PubMed

Mama, Mohammedaman; Alemu, Getaneh

2016-02-01

Globally about one third of the total population is estimated to be infected with intestinal parasites, of which, the majority are people living in tropical and sub-tropical parts of the world. Cases of intestinal parasitosis are also highly abundant in Ethiopia and hence the aim of present study was to assess prevalence and predictors of intestinal parasitic infections among food handlers working in Arba Minch University students' cafeteria, South Ethiopia. A cross sectional study was conducted among food handlers working in Arba Minch University from April to June, 2015. A pretested structured questionnaire was used for collecting data about socio-demographic characteristics and possible risk factors. Stool specimens were collected and examined microscopically for the presence of eggs, cysts and trophozoites of intestinal parasites. Data entry and analysis were done using SPSS version 20 software. A total of 376 food handlers were enrolled in the study of which thirty one of them were not willing to participate for a stool examination. The majority of study participants were females 273 (72.6 %). About 123 (36 %) of food handlers were found to be positive for different intestinal parasites with the most abundant parasite of Entamoeba histolytica/dispar 48 (14 %) followed by Ascaris lumbricoides 32 (9.27 %). Finger nail status (AOR: 2.2, 95 % CI: 1.29-3.72), hand washing practice after toilet (AOR: 1.71, 95 % CI: 1.06-2.77), hand washing practice before food handling (AOR: 1.69, 95 % CI: 1.04-2.75), preparing food when suffering from diseases (AOR: 3.08, 95 % CI: 1.17-8.13), and using common knife for cutting raw flesh food and other food (AOR: 1.72, 95 % CI: 1.01-2.92) were independent predictors of intestinal parasitic infection among the food handlers. This study revealed a high prevalence of intestinal parasites among food handlers. Since most of the intestinal parasites are transmitted by the feco-oral route, food handlers could be an important source of

The Impact of Intestinal Parasitic Infections on the Nutritional Status of Rural and Urban School-Aged Children in Nigeria.

PubMed

Opara, Kenneth N; Udoidung, Nsima I; Opara, Dominic C; Okon, Okpok E; Edosomwan, Evelyn U; Udoh, Anietie J

2012-01-01

Intestinal parasitic infection and undernutrition are still major public health problems in poor and developing countries. The objective of this study was to assess the relationship between intestinal parasitic infection and nutritional status in 405 primary school children from rural and urban areas of Akwa Ibom State, Nigeria. This cross-sectional survey in 2009 obtained anthropometric data, height-for-age (HA), weight-for-height (WH) and weight-for-age (WA) Z-scores from each child and fecal samples were also collected and screened for intestinal parasites using standard parasitological protocols. The prevalence of infection with any intestinal parasite was 67.4%. A total of six intestinal parasites were detected; hookworm (41.7%) had the highest prevalence. The prevalence of intestinal parasites and undernutrition was significantly higher in rural than in urban children (P<0.001). The prevalence of stunting (HAZ < -2), underweight (WAZ < -2) and wasting (WHZ < -2) for rural and urban children were 42.3% vs. 29.7%; underweight 43.2% vs. 29.6% and wasting 10.9% vs. 6.4%, respectively. With respect to nutritional indicators, the infected children had significantly (P<0.05) higher z-scores than the uninfected children. Multivariate logistic regression analysis showed that only Hookworm and Ascaris lumbricoides were each significantly (P<0.05) associated with stunting, wasting, and underweight. Since intestinal parasitic infections are associated with malnutrition, controlling these parasites could increase the physical development and well-being of the affected children.

Evasion and Immuno-Endocrine Regulation in Parasite Infection: Two Sides of the Same Coin in Chagas Disease?

PubMed

Morrot, Alexandre; Villar, Silvina R; González, Florencia B; Pérez, Ana R

2016-01-01

Chagas disease is a serious illness caused by the protozoan parasite Trypanosoma cruzi. Nearly 30% of chronically infected people develop cardiac, digestive, or mixed alterations, suggesting a broad range of host-parasite interactions that finally impact upon chronic disease outcome. The ability of T. cruzi to persist and cause pathology seems to depend on diverse factors like T. cruzi strains, the infective load and the route of infection, presence of virulence factors, the parasite capacity to avoid protective immune response, the strength and type of host defense mechanisms and the genetic background of the host. The host-parasite interaction is subject to a constant neuro-endocrine regulation that is thought to influence the adaptive immune system, and as the infection proceeds it can lead to a broad range of outcomes, ranging from pathogen elimination to its continued persistence in the host. In this context, T. cruzi evasion strategies and host defense mechanisms can be envisioned as two sides of the same coin, influencing parasite persistence and different outcomes observed in Chagas disease. Understanding how T. cruzi evade host's innate and adaptive immune response will provide important clues to better dissect mechanisms underlying the pathophysiology of Chagas disease.

Evasion and Immuno-Endocrine Regulation in Parasite Infection: Two Sides of the Same Coin in Chagas Disease?

PubMed Central

Morrot, Alexandre; Villar, Silvina R.; González, Florencia B.; Pérez, Ana R.

2016-01-01

Chagas disease is a serious illness caused by the protozoan parasite Trypanosoma cruzi. Nearly 30% of chronically infected people develop cardiac, digestive, or mixed alterations, suggesting a broad range of host-parasite interactions that finally impact upon chronic disease outcome. The ability of T. cruzi to persist and cause pathology seems to depend on diverse factors like T. cruzi strains, the infective load and the route of infection, presence of virulence factors, the parasite capacity to avoid protective immune response, the strength and type of host defense mechanisms and the genetic background of the host. The host-parasite interaction is subject to a constant neuro-endocrine regulation that is thought to influence the adaptive immune system, and as the infection proceeds it can lead to a broad range of outcomes, ranging from pathogen elimination to its continued persistence in the host. In this context, T. cruzi evasion strategies and host defense mechanisms can be envisioned as two sides of the same coin, influencing parasite persistence and different outcomes observed in Chagas disease. Understanding how T. cruzi evade host's innate and adaptive immune response will provide important clues to better dissect mechanisms underlying the pathophysiology of Chagas disease. PMID:27242726

Community awareness of intestinal parasites and the prevalence of infection among community members of rural Abaye Deneba area, Ethiopia.

PubMed

Nyantekyi, Liza; Legesse, Mengistu; Medhin, Girmay; Animut, Abebe; Tadesse, Konjit; Macias, Chanda; Degarege, Abraham; Erko, Berhanu

2014-05-01

To assess the knowledge of Abaye Deneba community members regarding intestinal parasites and prevalence of intestinal parasitic infections. Knowledge about intestinal parasites was assessed by administering a questionnaire to 345 randomly selected household heads. Parasitological stool examination of 491 randomly selected individuals was done using the formol ether concentration technique. Knowledge of the Abaye Deneba community about parasitic diseases such as schistosomiasis, amoebiasis, ascariasis and taeniasis was very low. However, 204 (59.3%) members correctly responded that the cause of giardiasis is related to contaminated water and 176 (51.2%) knew how to prevent it. In some cases, respondents did correctly identify causes, symptoms of intestinal parasite infection and ways to prevent it, but they did not accurately link it to the appropriate disease caused by the different intestinal parasite species. Among the 491 stool samples examined, 50.2% of study participants showed infection with at least one intestinal parasite. Schistosoma mansoni was the most prevalent (41.3%) followed by Trichuris trichiura(9.4%), Ascaris lumbricoides (8.4%), Taenia saginata (2.4%), Enterobius vermicularis (2.0%) and hookworm (0.4%). Prevalence of schistosomiasis was highest in men aged 15-24 years. Intestinal parasitic infection is highly prevalent in communities of the Abaye Deneba area. Nevertheless, the knowledge of the community members about the parasite is less. Implementation of preventive chemotherapy, supplemented with health education, provision and use of sanitary facilities would be recommended to reduce morbidity and control transmission of intestinal parasites in this area.

Extreme habitats as refuge from parasite infections? Evidence from an extremophile fish

NASA Astrophysics Data System (ADS)

Tobler, Michael; Schlupp, Ingo; García de León, Francisco J.; Glaubrecht, Matthias; Plath, Martin

2007-05-01

Living in extreme habitats typically requires costly adaptations of any organism tolerating these conditions, but very little is known about potential benefits that trade off these costs. We suggest that extreme habitats may function as refuge from parasite infections, since parasites can become locally extinct either directly, through selection by an extreme environmental parameter on free-living parasite stages, or indirectly, through selection on other host species involved in its life cycle. We tested this hypothesis in a small freshwater fish, the Atlantic molly ( Poecilia mexicana) that inhabits normal freshwaters as well as extreme habitats containing high concentrations of toxic hydrogen sulfide. Populations from such extreme habitats are significantly less parasitized by the trematode Uvulifer sp. than a population from a non-sulfidic habitat. We suggest that reduced parasite prevalence may be a benefit of living in sulfidic habitats.

Parasite-mediated heterozygote advantage in an outbred songbird population

PubMed Central

MacDougall-Shackleton, Elizabeth A; Derryberry, Elizabeth P; Foufopoulos, Johannes; Dobson, Andrew P; Hahn, Thomas P

2005-01-01

Coevolution with parasites is thought to maintain genetic diversity in host populations. However, while there are sound theoretical reasons to expect heterozygosity and parasite resistance to be related, this pattern has generally been shown only in inbred laboratory and island populations. This leaves doubt as to whether parasite-mediated selection for genetic diversity is in fact a general process. Here we show that haematozoan parasite load is linked to two complementary measures of microsatellite variability in an outbred population of mountain white-crowned sparrows (Zonotrichia leucophrys oriantha) for which we know that parasites reduce fitness. Moreover, each of the genetic measures predicts a subtly different aspect of parasitism. Microsatellite heterozygosity is related to an individual's risk of parasitism, and mean d2 (a broader, more long-term measure of parental relatedness) to the severity of infection among parasitized individuals. PMID:17148140

The influence of poverty and culture on the transmission of parasitic infections in rural nicaraguan villages.

PubMed

Karan, Abraar; Chapman, Gretchen B; Galvani, Alison

2012-01-01

Intestinal parasitic infections cause one of the largest global burdens of disease. To identify possible areas for interventions, a structured questionnaire addressing knowledge, attitude, and practice regarding parasitic infections as well as the less studied role of culture and resource availability was presented to mothers of school-age children in rural communities around San Juan del Sur, Nicaragua. We determined that access to resources influenced knowledge, attitude, and behaviors that may be relevant to transmission of parasitic infections. For example, having access to a clinic and prior knowledge about parasites was positively correlated with the practice of having fencing for animals, having fewer barefoot children, and treating children for parasites. We also found that cultural beliefs may contribute to parasitic transmission. Manifestations of machismo culture and faith in traditional medicines conflicted with healthy practices. We identified significant cultural myths that prevented healthy behaviors, including the beliefs that cutting a child's nails can cause tetanus and that showering after a hot day caused sickness. The use of traditional medicine was positively correlated with the belief in these cultural myths. Our study demonstrates that the traditional knowledge, attitude, and practice model could benefit from including components that examine resource availability and culture.

Effect of enteric parasitic infection on serum trace elements and nutritional status in upper Egyptian children

PubMed Central

Yones, Doaa A; Galal, Lamia A; Abdallah, Alameldin M; Zaghlol, Khaled S

2015-01-01

Introduction: Enteric parasitic infections still the cause of major health problems among Egyptian children as they have great morbid effect on their physical and cognitive development. Malnutrition makes children more prone to micronutrient deficiency and subsequently more vulnerable to parasitic infection. The present study aimed to identify the effect of intestinal parasitism on micronutrient serum level and children nutritional status. Materials and Methods: A case control study was carried out on children from 1 to 6 years old who were attending the Assiut University Children Hospital outpatient clinic, after parasitological stool examination they were divided into Group 1 (G1, n: 60) positive with enteric parasite and Group 2 (G2, n: 60) age and sex matched and free of parasites. Anthropometric measurements were expressed as weight for age (WFA), height for age (HFA), and weight for height (WFH) parameters. Serum zinc (Zn) and copper (Cu) were determined by atomic absorption spectrophotometer. Results: Intestinal parasitic infection rate was 55.7%; more commonly detected parasites were Giardia lamblia 28%, Cryptosporidium sp. 20%, and polyparasitism 18%. All children (G1 and G2) were underweight (WFA) while 63% of G1 were malnourished, either in the form of wasting (WFH) or stunting (HFA) or both aspects. Stunting and wasting were more dominant among children infected with G. lamblia and Cryptosporidium sp. and most of them were below 2 years old. Conclusions: Coincident decrease in serum Zn level and an increase of serum Cu was more prominent among G. lamblia and Cryptosporidium sp. patients. G. lamblia and Cryptosporidium sp. were found to be more associated with nonstandard children nutritional status beside to an altered micronutrient level. PMID:25709950

Distribution and transmission of the highly pathogenic parasite Ichthyophonus in marine fishes of Alaska

USGS Publications Warehouse

Gregg, Jacob L.; Grady, Courtney A.; Thompson, Rachel L.; Purcell, Maureen K.; Friedman, Carolyn S.; Hershberger, Paul K.

2014-01-01

A combination of field surveys, molecular typing, and laboratory experiments were used to improve our understanding of the distribution and transmission mechanisms of fish parasites in the genus Ichthyophonus. Ichthyophonus spp. infections were detected from the Bering Sea to the coast of Oregon in 10 of 13 host species surveyed. Sequences of rDNA extracted from these isolates indicate that a ubiquitous Ichthyophonus type occurs in the NE Pacific Ocean and Bering Sea and accounts for nearly all the infections encountered. Among NE Pacific isolates, only parasites from yellowtail rockfish and Puget Sound rockfish varied at the DNA locus examined. These data suggest that a single source population of these parasites is available to fishes in diverse niches across a wide geographic range. A direct life cycle within a common forage species could account for the relatively low parasite diversity we encountered. In the laboratory we tested the hypothesis that waterborne transmission occurs among Pacific herring, a common NE Pacific forage species. No horizontal transmission occurred during a four-month cohabitation experiment involving infected herring and conspecific sentinels. The complete life cycle of Ichthyophonus spp. is not known, but these results suggest that system-wide processes maintain a relatively homogenous parasite population.

Immune response in the adipose tissue of lean mice infected with the protozoan parasite Neospora caninum

PubMed Central

Teixeira, Luzia; Moreira, João; Melo, Joana; Bezerra, Filipa; Marques, Raquel M; Ferreirinha, Pedro; Correia, Alexandra; Monteiro, Mariana P; Ferreira, Paula G; Vilanova, Manuel

2015-01-01

The adipose tissue can make important contributions to immune function. Nevertheless, only a limited number of reports have investigated in lean hosts the immune response elicited in this tissue upon infection. Previous studies suggested that the intracellular protozoan Neospora caninum might affect adipose tissue physiology. Therefore, we investigated in mice challenged with this protozoan if immune cell populations within adipose tissue of different anatomical locations could be differently affected. Early in infection, parasites were detected in the adipose tissue and by 7 days of infection increased numbers of macrophages, regulatory T (Treg) cells and T-bet+ cells were observed in gonadal, mesenteric, omental and subcutaneous adipose tissue. Increased expression of interferon-γ was also detected in gonadal adipose tissue of infected mice. Two months after infection, parasite DNA was no longer detected in these tissues, but T helper type 1 (Th1) cell numbers remained above control levels in the infected mice. Moreover, the Th1/Treg cell ratio was higher than that of controls in the mesenteric and subcutaneous adipose tissue. Interestingly, chronically infected mice presented a marked increase of serum leptin, a molecule that plays a role in energy balance regulation as well as in promoting Th1-type immune responses. Altogether, we show that an apicomplexa parasitic infection influences immune cellular composition of adipose tissue throughout the body as well as adipokine production, still noticed at a chronic phase of infection when parasites were already cleared from that particular tissue. This strengthens the emerging view that infections can have long-term consequences for the physiology of adipose tissue. PMID:25581844

Long-term live imaging reveals cytosolic immune responses of host hepatocytes against Plasmodium infection and parasite escape mechanisms

PubMed Central

Prado, Monica; Eickel, Nina; De Niz, Mariana; Heitmann, Anna; Agop-Nersesian, Carolina; Wacker, Rahel; Schmuckli-Maurer, Jacqueline; Caldelari, Reto; Janse, Chris J; Khan, Shahid M; May, Jürgen; Meyer, Christian G; Heussler, Volker T

2015-01-01

Plasmodium parasites are transmitted by Anopheles mosquitoes to the mammalian host and actively infect hepatocytes after passive transport in the bloodstream to the liver. In their target host hepatocyte, parasites reside within a parasitophorous vacuole (PV). In the present study it was shown that the parasitophorous vacuole membrane (PVM) can be targeted by autophagy marker proteins LC3, ubiquitin, and SQSTM1/p62 as well as by lysosomes in a process resembling selective autophagy. The dynamics of autophagy marker proteins in individual Plasmodium berghei-infected hepatocytes were followed by live imaging throughout the entire development of the parasite in the liver. Although the host cell very efficiently recognized the invading parasite in its vacuole, the majority of parasites survived this initial attack. Successful parasite development correlated with the gradual loss of all analyzed autophagy marker proteins and associated lysosomes from the PVM. However, other autophagic events like nonselective canonical autophagy in the host cell continued. This was indicated as LC3, although not labeling the PVM anymore, still localized to autophagosomes in the infected host cell. It appears that growing parasites even benefit from this form of nonselective host cell autophagy as an additional source of nutrients, as in host cells deficient for autophagy, parasite growth was retarded and could partly be rescued by the supply of additional amino acid in the medium. Importantly, mouse infections with P. berghei sporozoites confirmed LC3 dynamics, the positive effect of autophagy activation on parasite growth, and negative effects upon autophagy inhibition. PMID:26208778

Co-infection of intestinal parasites and Helicobacter pylori among upper gastrointestinal symptomatic adult patients attending Mekanesalem Hospital, northeast Ethiopia.

PubMed

Seid, Abdurahaman; Tamir, Zemenu; Kasanew, Brhanu; Senbetay, Moges

2018-02-20

Intestinal parasites and H. pylori are well-known for their high prevalence worldwide. Thus, the objective of this study waste assess risk factors and co-infection of intestinal parasites and H. pylori among adult patients with upper gastrointestinal complaints. A hospital-based cross sectional study was conducted among 363 consecutive adult patients from December 10, 2015 to February 30,2016. Stool and venous blood were collected for analysis of Intestinal parasites and H. pylori infection, respectively. Data was analyzed using SPSS version 16 and logistic regression analysis was carried out to assess predictors of co-infection. A p ≤ 0.05 was considered as statistically significant. Helicobacter pylori IgG and intestinal parasites were detected in 70.25-38.3% of participants, respectively while G. lamblia accounted 22.3%. G. lamblia prevalence was significantly higher among H. pylori infected participants (COR: 2.76; 95% CI: 1.46-5.23), but E. hystolytica/dispar infection didn't show significant variation (p = 0.15). H. pylori and intestinal parasites concomitant co-infection was associated with male sex (AOR: 1.61; 95% CI: 1.01-2.56), consumption of river water (AOR: 1.85; 95% CI: 1.11-3.07) and ground/spring water (AOR: 4.10; 95% CI: 1.97-8.52). Thus, besides H. pylori investigation, upper gastrointestinal symptomatic patients should be screened for G. lamblia infection and other intestinal parasites.

Parasite-mediated nuclear factor κB regulation in lymphoproliferation caused by Theileria parva infection

PubMed Central

Palmer, Guy H.; Machado, Joel; Fernandez, Paula; Heussler, Volker; Perinat, Therese; Dobbelaere, Dirk A. E.

1997-01-01

Infection of cattle with the protozoan Theileria parva results in uncontrolled T lymphocyte proliferation resulting in lesions resembling multicentric lymphoma. Parasitized cells exhibit autocrine growth characterized by persistent translocation of the transcriptional regulatory factor nuclear factor κB (NFκB) to the nucleus and consequent enhanced expression of interleukin 2 and the interleukin 2 receptor. How T. parva induces persistent NFκB activation, required for T cell activation and proliferation, is unknown. We hypothesized that the parasite induces degradation of the IκB molecules which normally sequester NFκB in the cytoplasm and that continuous degradation requires viable parasites. Using T. parva-infected T cells, we showed that the parasite mediates continuous phosphorylation and proteolysis of IκBα. However, IκBα reaccumulated to high levels in parasitized cells, which indicated that T. parva did not alter the normal NFκB-mediated positive feedback loop which restores cytoplasmic IκBα. In contrast, T. parva mediated continuous degradation of IκBβ resulting in persistently low cytoplasmic IκBβ levels. Normal IκBβ levels were only restored following T. parva killing, indicating that viable parasites are required for IκBβ degradation. Treatment of T. parva-infected cells with pyrrolidine dithiocarbamate, a metal chelator, blocked both IκB degradation and consequent enhanced expression of NFκB dependent genes. However treatment using the antioxidant N-acetylcysteine had no effect on either IκB levels or NFκB activation, indicating that the parasite subverts the normal IκB regulatory pathway downstream of the requirement for reactive oxygen intermediates. Identification of the critical points regulated by T. parva may provide new approaches for disease control as well as increase our understanding of normal T cell function. PMID:9356483

Cutaneous cytomegalovirus infection in a patient with acquired immunodeficiency syndrome.

PubMed

AbdullGaffar, Badr; Raman, Lakshmiah G; Al Muala, Alia

2008-09-01

Abstract Cytomegalovirus (CMV) infection in immunocompromised patients is a common opportunistic systemic infection which can lead to death, and usually presents with visceral manifestations, especially of the lung, brain, eye, and gastrointestinal tract. Cutaneous CMV infection is, however, relatively rare in immunocompromised patients. Cutaneous CMV infection can have variable clinical and histologic manifestations, and thus can be easily missed. We report a case of cutaneous CMV infection in a patient with acquired immunodeficiency syndrome, presenting as a generalized, pruritic, erythematous, maculopapular eruption.

Diagnosing Medical Parasites: A Public Health Officers Guide to Assisting Laboratory and Medical Officers

DTIC Science & Technology

2009-01-01

an infection usually caused by the pathogenic Entamoeba histolytica / dispar, and is commonly an infection of the colon. It has a world wide...The parasitic adult females lay eggs while they are in the duodenum where they hatch producing rhabditiform (non- infective ) larvae. 1. The... females begin to oviposit 60 to 70 days after infection . Female worms in the cecum shed between 3,000 and 20,000 eggs per day. The life span of the

Association of enteric parasitic infections with intestinal inflammation and permeability in asymptomatic infants of São Tomé Island.

PubMed

Garzón, Marisol; Pereira-da-Silva, Luis; Seixas, Jorge; Papoila, Ana Luísa; Alves, Marta; Ferreira, Filipa; Reis, Ana

2017-05-01

The cumulative effect of repeated asymptomatic enteric infections on intestinal barrier is not fully understood in infants. We aimed to evaluate the association between previous enteric parasitic infections and intestinal inflammation and permeability at 24-months of age, in asymptomatic infants of São Tomé Island. A subset of infants from a birth cohort, with intestinal parasite evaluations in at least four points of assessment, was eligible. Intestinal inflammatory response and permeability were assessed using fecal S100A12 and alpha-1-antitrypsin (A1AT), respectively. The cutoff <-1SD for weight-for-length and length-for-age was used to define wasting and stunting. Multivariable linear regression analysis explored if cumulative enteric parasitic infections explained variability of fecal biomarkers, after adjusting for potential confounders. Eighty infants were included. Giardia duodenalis and soil-transmitted helminths (STH) were the most frequent parasites. The median (interquartile range) levels were 2.87 μg/g (2.41-3.92) for S100A12 and 165.1 μg/g (66.0-275.6) for A1AT. Weak evidence of association was found between S100A12 levels and G. duodenalis (p = 0.080) and STH infections (p = 0.089), and between A1AT levels and parasitic infection of any etiology (p = 0.089), at 24-months of age. Significant associations between A1AT levels and wasting (p = 0.006) and stunting (p = 0.044) were found. Previous parasitic infections were not associated with fecal biomarkers at 24 months of age. To summarize, previous asymptomatic parasitic infections showed no association with intestinal barrier dysfunction. Notwithstanding, a tendency toward increased levels of the inflammatory biomarker was observed for current G. duodenalis and STH infections, and increased levels of the permeability biomarker were significantly associated with stunting and wasting.

The epidemiology of pseudallescheriasis complicating transplantation: Nosocomial and community-acquired infection.

PubMed

Patterson, T F; Andriole, V T; Zervos, M J; Therasse, D; Kauffman, Carol A

1990-06-01

The epidemiology of two cases of pseudallescheriasis in organ transplant patients are described and the disease in that population is reviewed. Disseminated hospital-acquired infection occurred in a liver transplant recipient and was fatal despite therapy with miconazole. A heart transplant recipient developed localized disease following soil contamination of soft tissue trauma which was cured with surgical resection and miconazole therapy. Itraconazole showed in vitro activity against Pseudallescheria boydii and should be evaluated in pseudallescheriasis. P. boydii infections are important complications of transplantation and should be considered in the differential diagnosis of community-acquired as well as nosocomial fungal infections in this population. © 1990 Grosse Verlag Berlin.

Prevention and Control of Antimicrobial Resistant Healthcare-Associated Infections: The Microbiology Laboratory Rocks!

PubMed

Simões, Alexandra S; Couto, Isabel; Toscano, Cristina; Gonçalves, Elsa; Póvoa, Pedro; Viveiros, Miguel; Lapão, Luís V

2016-01-01

In Europe, each year, more than four milion patients acquire a healthcare-associated infection (HAI) and almost 40 thousand die as a direct consequence of it. Regardless of many stategies to prevent and control HAIs, they remain an important cause of morbidity and mortality worldwide with a significant economic impact: a recent estimate places it at the ten billion dollars/year. The control of HAIs requires a prompt and efficient identification of the etiological agent and a rapid communication with the clinician. The Microbiology Laboratory has a significant role in the prevention and control of these infections and is a key element of any Infection Control Program. The work of the Microbiology Laboratory covers microbial isolation and identification, determination of antimicrobial susceptibility patterns, epidemiological surveillance and outbreak detection, education, and report of quality assured results. In this paper we address the role and importance of the Microbiology Laboratory in the prevention and control of HAI and in Antibiotic Stewardship Programs and how it can be leveraged when combined with the use of information systems. Additionally, we critically review some challenges that the Microbiology Laboratory has to deal with, including the selection of analytic methods and the proper use of communication channels with other healthcare services.

Parasites in the City: Degree of Urbanization Predicts Poxvirus and Coccidian Infections in House Finches (Haemorhous mexicanus)

PubMed Central

Giraudeau, Mathieu; Mousel, Melanie; Earl, Stevan; McGraw, Kevin

2014-01-01

Background Urbanization can strongly impact the physiology, behavior, and fitness of animals. Conditions in cities may also promote the transmission and success of animal parasites and pathogens. However, to date, no studies have examined variation in the prevalence or severity of several distinct pathogens/parasites along a gradient of urbanization in animals or if these infections increase physiological stress in urban populations. Methodology/Principal Findings Here, we measured the prevalence and severity of infection with intestinal coccidians (Isospora sp.) and the canarypox virus (Avipoxvirus) along an urban-to-rural gradient in wild male house finches (Haemorhous mexicanus). In addition, we quantified an important stress indicator in animals (oxidative stress) and several axes of urbanization, including human population density and land-use patterns within a 1 km radius of each trapping site. Prevalence of poxvirus infection and severity of coccidial infection were significantly associated with the degree of urbanization, with an increase of infection in more urban areas. The degrees of infection by the two parasites were not correlated along the urban-rural gradient. Finally, levels of oxidative damage in plasma were not associated with infection or with urbanization metrics. Conclusion/Significance These results indicate that the physical presence of humans in cities and the associated altered urban landscape characteristics are associated with increased infections with both a virus and a gastrointestinal parasite in this common songbird resident of North American cities. Though we failed to find elevations in urban- or parasite/pathogen-mediated oxidative stress, humans may facilitate infections in these birds via bird feeders (i.e. horizontal disease transmission due to unsanitary surfaces and/or elevations in host population densities) and/or via elevations in other forms of physiological stress (e.g. corticosterone, nutritional). PMID:24503816

Temperature rise and parasitic infection interact to increase the impact of an invasive species.

PubMed

Laverty, Ciaran; Brenner, David; McIlwaine, Christopher; Lennon, Jack J; Dick, Jaimie T A; Lucy, Frances E; Christian, Keith A

2017-04-01

Invasive species often detrimentally impact native biota, e.g. through predation, but predicting such impacts is difficult due to multiple and perhaps interacting abiotic and biotic context dependencies. Higher mean and peak temperatures, together with parasites, might influence the impact of predatory invasive host species additively, synergistically or antagonistically. Here, we apply the comparative functional response methodology (relationship between resource consumption rate and resource supply) in one experiment and conduct a second scaled-up mesocosm experiment to assess any differential predatory impacts of the freshwater invasive amphipod Gammarus pulex, when uninfected and infected with the acanthocephalan Echinorhynchus truttae, at three temperatures representative of current and future climate. Individual G. pulex showed Type II predatory functional responses. In both experiments, infection was associated with higher maximum feeding rates, which also increased with increasing temperatures. Additionally, infection interacted with higher temperatures to synergistically elevate functional responses and feeding rates. Parasitic infection also generally increased Q 10 values. We thus suggest that the differential metabolic responses of the host and parasite to increasing temperatures drives the synergy between infection and temperature, elevating feeding rates and thus enhancing the ecological impact of the invader. Copyright © 2017 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

The Dialogue of the Host-Parasite Relationship: Leishmania spp. and Trypanosoma cruzi Infection.

PubMed

de Morais, Carlos Gustavo Vieira; Castro Lima, Ana Karina; Terra, Rodrigo; dos Santos, Rosiane Freire; Da-Silva, Silvia Amaral Gonçalves; Dutra, Patrícia Maria Lourenço

2015-01-01

The intracellular protozoa Leishmania spp. and Trypanosoma cruzi and the causative agents of Leishmaniasis and Chagas disease, respectively, belong to the Trypanosomatidae family. Together, these two neglected tropical diseases affect approximately 25 million people worldwide. Whether the host can control the infection or develops disease depends on the complex interaction between parasite and host. Parasite surface and secreted molecules are involved in triggering specific signaling pathways essential for parasite entry and intracellular survival. The recognition of the parasite antigens by host immune cells generates a specific immune response. Leishmania spp. and T. cruzi have a multifaceted repertoire of strategies to evade or subvert the immune system by interfering with a range of signal transduction pathways in host cells, which causes the inhibition of the protective response and contributes to their persistence in the host. The current therapeutic strategies in leishmaniasis and trypanosomiasis are very limited. Efficacy is variable, toxicity is high, and the emergence of resistance is increasingly common. In this review, we discuss the molecular basis of the host-parasite interaction of Leishmania and Trypanosoma cruzi infection and their mechanisms of subverting the immune response and how this knowledge can be used as a tool for the development of new drugs.

The Dialogue of the Host-Parasite Relationship: Leishmania spp. and Trypanosoma cruzi Infection

PubMed Central

de Morais, Carlos Gustavo Vieira; Castro Lima, Ana Karina; dos Santos, Rosiane Freire; Da-Silva, Silvia Amaral Gonçalves; Dutra, Patrícia Maria Lourenço

2015-01-01

The intracellular protozoa Leishmania spp. and Trypanosoma cruzi and the causative agents of Leishmaniasis and Chagas disease, respectively, belong to the Trypanosomatidae family. Together, these two neglected tropical diseases affect approximately 25 million people worldwide. Whether the host can control the infection or develops disease depends on the complex interaction between parasite and host. Parasite surface and secreted molecules are involved in triggering specific signaling pathways essential for parasite entry and intracellular survival. The recognition of the parasite antigens by host immune cells generates a specific immune response. Leishmania spp. and T. cruzi have a multifaceted repertoire of strategies to evade or subvert the immune system by interfering with a range of signal transduction pathways in host cells, which causes the inhibition of the protective response and contributes to their persistence in the host. The current therapeutic strategies in leishmaniasis and trypanosomiasis are very limited. Efficacy is variable, toxicity is high, and the emergence of resistance is increasingly common. In this review, we discuss the molecular basis of the host-parasite interaction of Leishmania and Trypanosoma cruzi infection and their mechanisms of subverting the immune response and how this knowledge can be used as a tool for the development of new drugs. PMID:26090399

Parasite burden in hamsters infected with two different strains of leishmania (Leishmania) infantum: "Leishman Donovan units" versus real-time PCR.

PubMed

Moreira, Nádia das Dores; Vitoriano-Souza, Juliana; Roatt, Bruno Mendes; Vieira, Paula Melo de Abreu; Ker, Henrique Gama; de Oliveira Cardoso, Jamille Mirelle; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; de Lana, Marta; Reis, Alexandre Barbosa

2012-01-01

To develop and test new therapeutics and immune prophylaxis strategies for visceral leishmaniasis (VL), understanding tissue parasitism evolution after experimental infection with Leishmania infantum is important. Experimental infection in a hamster model (Mesocricetus auratus) reproduces several typical aspects of canine and human VL that are closely related to the inoculum's route. We quantified the parasitism in the liver and spleen of hamsters experimentally infected by various routes (intradermal, intraperitoneal, and intracardiac [IC]) and different strains of L. infantum (MHOM/BR/74/PP75 and Wild) and compared two different methodologies to evaluate tissue parasitism (Leishman Donovan units [LDU] and real-time qPCR). In addition, the quantification of specific total-IgG in the serum of uninfected and infected hamsters was determined by ELISA. The animals were followed for 1, 3, 6 and 9 months post-infection for survival analysis. We found that infection with the Wild strain by the IC route resulted in higher mortality. Positive antibody (IgG) responses were detected with higher peaks at 6 and 9 months in the IC group inoculated with PP75 strain. However, in animals infected with the Wild strain the IgG levels were elevated in all infected groups during all the time evaluated. We also observed by LDU analysis that the IC route lead to higher parasitism in the liver and spleen with both strains. Furthermore, qPCR showed higher sensitivity for identifying animals with low parasitic burden. In conclusion, qPCR can be useful for assessing parasitism in the spleen and liver of a hamster model infected with L. infantum independent of the route of infection, and this technique may become an essential tool for assessing parasite density in the hamster model after experimental treatment or immunization with potential vaccine candidates.

Epidemiological Profile and Risk Factors for Acquiring HBV and/or HCV in HIV-Infected Population Groups in Nepal.

PubMed

Bhattarai, Manjula; Baniya, Jagat Bahadur; Aryal, Nirmal; Shrestha, Bimal; Rauniyar, Ramanuj; Adhikari, Anurag; Koirala, Pratik; Oli, Pardip Kumar; Pandit, Ram Deo; Stein, David A; Gupta, Birendra Prasad

2018-01-01

HBV and HCV infections are widespread among the HIV-infected individuals in Nepal. The goals of this study were to investigate the epidemiological profile and risk factors for acquiring HBV and/or HCV coinfection in disadvantaged HIV-positive population groups in Nepal. We conducted a retrospective study on blood samples from HIV-positive patients from the National Public Health Laboratory at Kathmandu to assay for HBsAg, HBeAg, and anti-HCV antibodies, HIV viral load, and CD4+ T cell count. Among 579 subjects, the prevalence of HIV-HBV, HIV-HCV, and HIV-HBV-HCV coinfections was 3.62%, 2.93%, and 0.34%, respectively. Multivariate regression analysis indicated that spouses of HIV-positive migrant labourers were at significant risk for coinfection with HBV infection, and an age of >40 years in HIV-infected individuals was identified as a significant risk factor for HCV coinfection. Overall our study indicates that disadvantaged population groups such as intravenous drug users, migrant workers and their spouses, female sex workers, and men who have sex with HIV-infected men are at a high and persistent risk of acquiring viral hepatitis. We conclude that Nepalese HIV patients should receive HBV and HCV diagnostic screening on a regular basis.

Imaging host cell-Leishmania interaction dynamics implicates parasite motility, lysosome recruitment, and host cell wounding in the infection process.

PubMed

Forestier, Claire-Lise; Machu, Christophe; Loussert, Celine; Pescher, Pascale; Späth, Gerald F

2011-04-21

Leishmania donovani causes human visceral leishmaniasis. The parasite infectious cycle comprises extracellular flagellated promastigotes that proliferate inside the insect vector, and intracellular nonmotile amastigotes that multiply within infected host cells. Using primary macrophages infected with virulent metacyclic promastigotes and high spatiotemporal resolution microscopy, we dissect the dynamics of the early infection process. We find that motile promastigotes enter macrophages in a polarized manner through their flagellar tip and are engulfed into host lysosomal compartments. Persistent intracellular flagellar activity leads to reorientation of the parasite flagellum toward the host cell periphery and results in oscillatory parasite movement. The latter is associated with local lysosomal exocytosis and host cell plasma membrane wounding. These findings implicate lysosome recruitment followed by lysosome exocytosis, consistent with parasite-driven host cell injury, as key cellular events in Leishmania host cell infection. This work highlights the role of promastigote polarity and motility during parasite entry. Copyright © 2011 Elsevier Inc. All rights reserved.

Update on pathology of ocular parasitic disease

PubMed Central

Das, Dipankar; Ramachandra, Varsha; Islam, Saidul; Bhattacharjee, Harsha; Biswas, Jyotirmay; Koul, Akanksha; Deka, Panna; Deka, Apurba

2016-01-01

Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field. PMID:27958200

Update on pathology of ocular parasitic disease.

PubMed

Das, Dipankar; Ramachandra, Varsha; Islam, Saidul; Bhattacharjee, Harsha; Biswas, Jyotirmay; Koul, Akanksha; Deka, Panna; Deka, Apurba

2016-11-01

Parasites are a group of eukaryotic organisms that may be free-living or form a symbiotic or parasitic relationship with the hosts. Consisting of over 800,000 recognized species, parasites may be unicellular (Protozoa) or multicellular (helminths and arthropods). The association of parasites with human population started long before the emergence of civilization. Parasitic zoonotic diseases are prevalent worldwide including India. Appropriate epidemiological data are lacking on existing zoonotic parasitic diseases, and newer diseases are emerging in our scenario. Systemic diseases such as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. Acquired Toxoplasma infections are rising in immune-deficient individuals. Amongst the ocular parasitic diseases, various protozoas such as Cystoidea, trematodes, tissue flagellates, sporozoas etc. affect humans in general and eyes in particular, in different parts of the world. These zoonoses seem to be a real health related problem globally. Recent intensification of research throughout the world has led to specialization in biological fields, creating a conducive situation for researchers interested in this subject. The basics of parasitology lie in morphology, pathology, and with recent updates in molecular parasitology, the scope has extended further. The current review is to address the recent update in ophthalmic parasites with special reference to pathology and give a glimpse of further research in this field.

Intestinal parasitic infections in children presenting with diarrhoea in outpatient and inpatient settings in an informal settlement of Nairobi, Kenya.

PubMed

Mbae, Cecilia Kathure; Nokes, David James; Mulinge, Erastus; Nyambura, Joyce; Waruru, Anthony; Kariuki, Samuel

2013-05-27

The distribution of and factors associated with intestinal parasitic infections are poorly defined in high risk vulnerable populations such as urban slums in tropical sub-Saharan Africa. In a cross sectional study, children aged 5 years and below who presented with diarrhoea were recruited from selected outpatient clinics in Mukuru informal settlement, and from Mbagathi District hospital, Nairobi, over a period of two years (2010-2011). Stool samples were examined for the presence of parasites using direct, formal-ether concentration method and the Modified Ziehl Neelsen staining technique. Overall, 541/2112 (25.6%) were positive for at least one intestinal parasite, with the common parasites being; Entamoeba histolytica, 225 (36.7%),Cryptosporidium spp. 187, (30.5%), Giardia lamblia, 98 (16%).The prevalence of intestinal parasites infection was higher among children from outpatient clinics 432/1577(27.4%) than among those admitted in hospital 109/535 (20.1%) p < 0.001. Infections with E. histolytica, and G. lamblia were higher among outpatients than inpatients (13.8% vs 1.3% p < 0.001 and 5.8% vs 1.3% p < 0.049) respectively, while infection with Cryptosporidium spp. was higher among inpatients than outpatients (15.3% vs 6.7%) respectively p < 0.001. Other parasites isolated among outpatients included Isospora belli, 19 (1.2%), Ascaris lumbricoides, 26 (1.6%), and Hymenolepis nana 12 (0.8%), with the remainder detected in less than ten samples each. HIV-infected participants were more likely to be infected with any parasite than uninfected participants, Adjusted Odds Ratio (AOR), 2.04, 95% CI, 1.55-2.67, p < 0.001), and with Cryptosporidium spp. (AOR, 2.96, 95% CI 2.07-4.21, p < 0.001).The inpatients were less likely to be infected with E. histolytica than outpatients (AOR, 0.11, 95% CI, 0.51-0.24, p < 0.001), but more likely for inpatients to be infected with Cryptosporidium spp. than outpatients (AOR, 1.91, 95% CI, 1.33-2.73, p�

Sexually Transmitted Infections Among Hospitalized Patients With Human Immunodeficiency Virus Infection and Acquired Immune Deficiency Syndrome (HIV/AIDS) in Zahedan, Southeastern Iran.

PubMed

Hashemi-Shahri, Seyed Mohammad; Sharifi-Mood, Batool; Kouhpayeh, Hamid-Reza; Moazen, Javad; Farrokhian, Mohsen; Salehi, Masoud

2016-09-01

Studies show that nearly 40 million people are living with human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) around the world and since the beginning of the epidemic, about 35 million have died from AIDS. Heterosexual intercourse is the most common route for transmission of HIV infection (85%). People with a sexually transmitted infection (STI), such as syphilis, genital herpes, chancroid, or bacterial vaginosis, are more likely to obtain HIV infection during sex. On the other hand, a patient with HIV can acquire other infections such as hepatitis C virus (HCV) and hepatitis B virus (HBV) and also STIs. Co-infections and co-morbidities can affect the treatment route of patients with HIV/AIDs. Sometimes, physicians should treat these infections before treating the HIV infection. Therefore, it is important to identify co-infection or comorbidity in patients with HIV/AIDS. This study was conducted in order to understand the prevalence of HIV/AIDS/STI co-infection. In this cross-sectional study, we evaluated all HIV/AIDS patients who were admitted to the infectious wards of Boo-Ali hospital (Southeastern Iran) between March 2000 and January 2015. All HIV/AIDS patients were studied for sexually transmitted infections (STI) such as syphilis, gonorrhea, hepatitis B virus (HBV) and genital herpes. A questionnaire including data on age, sex, job, history of vaccination against HBV, hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), hepatitis B surface antigen (anti-HBs), HCV-Ab, venereal disease research laboratory (VDRL) test, fluorescent treponemal antibody absorption (FTA-Abs) test, and urine culture was designed. Data was analyzed by the Chi square test and P values of < 0.05 were considered significant. Among the 41 patients with HIV/AIDS (11 females and 30 males; with age range of 18 to 69 years) five cases (12.1%) had a positive test (1:8 or more) for VDRL. The FTA-Abs was positive for all patients who

Community-acquired Clostridium difficile infection in children: A retrospective study.

PubMed

Borali, Elena; Ortisi, Giuseppe; Moretti, Chiara; Stacul, Elisabetta Francesca; Lipreri, Rita; Gesu, Giovanni Pietro; De Giacomo, Costantino

2015-10-01

Community acquired-Clostridium difficile infection (CDI) has increased also in children in the last years. To determine the incidence of community-acquired CDI and to understand whether Clostridium difficile could be considered a symptom-triggering pathogen in infants. A five-year retrospective analysis (January 2007-December 2011) of faecal specimens from 124 children hospitalized in the Niguarda Ca' Granda Hospital for prolonged or muco-haemorrhagic diarrhoea was carried out. Stool samples were evaluated for common infective causes of diarrhoea and for Clostridium difficile toxins. Patients with and without CDI were compared for clinical characteristics and known risk factors for infection. Twenty-two children with CDI were identified in 5 years. An increased incidence of community-acquired CDI was observed, ranging from 0.75 per 1000 hospitalizations in 2007 to 9.8 per 1000 hospitalizations in 2011. Antimicrobial treatment was successful in all 19 children in whom it was administered; 8/22 CDI-positive children were younger than 2 years. No statistically significant differences in clinical presentation were observed between patients with and without CDI, nor in patients with and without risk factors for CDI. Our study shows that Clostridium difficile infection is increasing and suggests a possible pathogenic role in the first 2 years of life. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Biting midges (Culicoides, Diptera) transmit Haemoproteus parasites of owls: evidence from sporogony and molecular phylogeny.

PubMed

Bukauskaitė, Dovilė; Žiegytė, Rita; Palinauskas, Vaidas; Iezhova, Tatjana A; Dimitrov, Dimitar; Ilgūnas, Mikas; Bernotienė, Rasa; Markovets, Mikhail Yu; Valkiūnas, Gediminas

2015-06-04

Haemoproteus parasites are widespread, and several species cause diseases both in birds and blood-sucking insects. These pathogens are transmitted by dipterans belonging to the Ceratopogonidae and Hippoboscidae, however certain vector species remain unknown for the majority of Haemoproteus spp. Owls are often infected by Haemoproteus parasites, but experimental studies on vectors of these infections are lacking. The aim of this study was to investigate sporogonic development of two widespread Haemoproteus parasites of owls, H. noctuae and H. syrnii in experimentally infected biting midges Culicoides impunctatus and Culicoides nubeculosus. We also followed in vitro sporogonic development of these infections and determined their phylogenetic relationships with Haemoproteus spp., for which vectors have been identified. Wild-caught C. impunctatus and laboratory reared C. nubeculosus were infected experimentally by allowing them to take blood meals on one individual long-eared owl (Asio otus) and one tawny owl (Strix aluco) harbouring mature gametocytes of H. noctuae (lineage hCIRCUM01) and H. syrnii (hCULCIB01), respectively. The engorged insects were maintained in the laboratory at 16-18 °C, and dissected at intervals in order to follow the development of ookinetes, oocysts and sporozoites. We also observed in vitro development of sexual stages of both parasites by exposure of infected blood to air. The parasite lineages were determined by polymerase chain reaction-based methods. Bayesian phylogeny was constructed in order to determine the relationships of owl parasites with other avian Haemoproteus spp., for which vectors have been identified. Both H. noctuae and H. syrnii completed sporogony in C. nubeculosus, and H. noctuae completed sporogony in C. impunctatus. Ookinetes, oocysts and sporozoites of these parasites were reported and described. Gametes and ookinetes of both species readily developed in vitro. In accordance with sporogony data, the phylogenetic