Polymeric immunoglobulin receptor in intestinal immune defense against the lumen-dwelling protozoan parasite Giardia.

PubMed

Davids, Barbara J; Palm, J E Daniel; Housley, Michael P; Smith, Jennifer R; Andersen, Yolanda S; Martin, Martin G; Hendrickson, Barbara A; Johansen, Finn-Eirik; Svärd, Staffan G; Gillin, Frances D; Eckmann, Lars

2006-11-01

The polymeric Ig receptor (pIgR) is conserved in mammals and has an avian homologue, suggesting evolutionarily important functions in vertebrates. It transports multimeric IgA and IgM across polarized epithelia and is highly expressed in the intestine, yet little direct evidence exists for its importance in defense against common enteric pathogens. In this study, we demonstrate that pIgR can play a critical role in intestinal defense against the lumen-dwelling protozoan parasite Giardia, a leading cause of diarrheal disease. The receptor was essential for the eradication of Giardia when high luminal IgA levels were required. Clearance of Giardia muris, in which IgA plays a dominant role, was severely compromised in pIgR-deficient mice despite significant fecal IgA output at 10% of normal levels. In contrast, eradication of the human strain Giardia lamblia GS/M, for which adaptive immunity is less IgA dependent in mice, was unaffected by pIgR deficiency, indicating that pIgR had no physiologic role when lower luminal IgA levels were sufficient for parasite elimination. Immune IgA was greatly increased in the serum of pIgR-deficient mice, conferred passive protection against Giardia, and recognized several conserved giardial Ags, including ornithine carbamoyltransferase, arginine deiminase, alpha-enolase, and alpha- and beta-giardins, that are also detected in human giardiasis. Corroborative observations were made in mice lacking the J chain, which is required for pIgR-dependent transepithelial IgA transport. These results, together with prior data on pIgR-mediated immune neutralization of luminal cholera toxin, suggest that pIgR is essential in intestinal defense against pathogenic microbes with high-level and persistent luminal presence.

Effect of Mass Stool Examination and Mass Treatment For Decreasing Intestinal Helminth and Protozoan Infection Rates in Bolivian Children: A Cross-Sectional Study.

PubMed

Asai, Takao; Còrdova Vidal, Claudia; Strauss, Wilma; Ikoma, Toshikazu; Endoh, Kazuo; Yamamoto, Masaharu

2016-12-01

Bolivia is one of the countries with a high intestinal helminth and protozoan infection rate. Despite the high prevalence of the parasitic infection, nationwide preventive measures for Bolivian children have not yet been implemented. We evaluated the effect of mass stool examination and treatment as a strategy for decreasing the infection rate. This study was conducted between 2013 and 2015 in children aged 2-18 years. A total of 2,033 stool samples (575 in 2013, 815 in 2014 and 642 in 2015) were collected and examined using the formalin-ether medical sedimentation method. As an anthelminthic medicine, nitazoxanide was given to all infected children within 2 months post-examination, each year. The effect of mass stool examination and treatment was evaluated based on the changes in the overall or individual parasitic infection rates during the study period. The overall parasitic infection rate decreased significantly from 65.2% in 2013 to 43.0% in 2015; a 22.2 percentage point decrease (P<0.001). Protozoan infection accounted for a large portion of the parasitic infections, in the following rates: 62.4% in 2013, 49.3% in 2014, and 41.0% in 2015. The rate of the most common helminth infection, Hymenolepis nana, decreased significantly from 9.0% in 2013 to 6.4% in 2014 to 3.4% in 2015 (P<0.001). Prevalence of the most common pathogenic protozoan infection, Entamoeba histolytica, decreased significantly from 19.0% in 2013 to 3.0% in 2015 (P<0.001). Conversely, the rate of Giardia intestinalis increased significantly from 16.5% in 2013 to 21.2% in 2015 (P<0.01). Mass stool examination and treatment for intestinal helminth and protozoan infections was effective for decreasing the overall parasitic infection rate in the study population, excluding Giardia intestinalis. Further studies on the long-term effect of mass stool examination and treatment for decreasing all intestinal parasitic infection rates in Bolivian children are needed.

The role of arginine and arginine-metabolizing enzymes during Giardia – host cell interactions in vitro

PubMed Central

2013-01-01

Background Arginine is a conditionally essential amino acid important in growing individuals and under non-homeostatic conditions/disease. Many pathogens interfere with arginine-utilization in host cells, especially nitric oxide (NO) production, by changing the expression of host enzymes involved in arginine metabolism. Here we used human intestinal epithelial cells (IEC) and three different isolates of the protozoan parasite Giardia intestinalis to investigate the role of arginine and arginine-metabolizing enzymes during intestinal protozoan infections. Results RNA expression analyses of major arginine-metabolizing enzymes revealed the arginine-utilizing pathways in human IECs (differentiated Caco-2 cells) grown in vitro. Most genes were constant or down-regulated (e.g. arginase 1 and 2) upon interaction with Giardia, whereas inducible NO synthase (iNOS) and ornithine decarboxylase (ODC) were up-regulated within 6 h of infection. Giardia was shown to suppress cytokine-induced iNOS expression, thus the parasite has both iNOS inducing and suppressive activities. Giardial arginine consumption suppresses NO production and the NO-degrading parasite protein flavohemoglobin is up-regulated in response to host NO. In addition, the secreted, arginine-consuming giardial enzyme arginine deiminase (GiADI) actively reduces T-cell proliferation in vitro. Interestingly, the effects on NO production and T cell proliferation could be reversed by addition of external arginine or citrulline. Conclusions Giardia affects the host’s arginine metabolism on many different levels. Many of the effects can be reversed by addition of arginine or citrulline, which could be a beneficial supplement in oral rehydration therapy. PMID:24228819

Prevalence and Risk Factors for Intestinal Protozoan Infections with Cryptosporidium, Giardia, Blastocystis and Dientamoeba among Schoolchildren in Tripoli, Lebanon.

PubMed

Osman, Marwan; El Safadi, Dima; Cian, Amandine; Benamrouz, Sadia; Nourrisson, Céline; Poirier, Philippe; Pereira, Bruno; Razakandrainibe, Romy; Pinon, Anthony; Lambert, Céline; Wawrzyniak, Ivan; Dabboussi, Fouad; Delbac, Frederic; Favennec, Loïc; Hamze, Monzer; Viscogliosi, Eric; Certad, Gabriela

2016-03-01

Intestinal protozoan infections are confirmed as major causes of diarrhea, particularly in children, and represent a significant, but often neglected, threat to public health. No recent data were available in Lebanon concerning the molecular epidemiology of protozoan infections in children, a vulnerable population at high risk of infection. In order to improve our understanding of the epidemiology of intestinal pathogenic protozoa, a cross-sectional study was conducted in a general pediatric population including both symptomatic and asymptomatic subjects. After obtaining informed consent from the parents or legal guardians, stool samples were collected in January 2013 from 249 children in 2 schools in Tripoli, Lebanon. Information obtained from a standard questionnaire included demographic characteristics, current symptoms, socioeconomic status, source of drinking water, and personal hygiene habits. After fecal examination by both microscopy and molecular tools, the overall prevalence of parasitic infections was recorded as 85%. Blastocystis spp. presented the highest infection rate (63%), followed by Dientamoeba fragilis (60.6%), Giardia duodenalis (28.5%) and Cryptosporidium spp. (10.4%). PCR was also performed to identify species and genotypes of Cryptosporidium, subtypes of Blastocystis, and assemblages of Giardia. Statistical analysis using a logistic regression model showed that contact with family members presenting gastrointestinal disorders was the primary risk factor for transmission of these protozoa. This is the first study performed in Lebanon reporting the prevalence and the clinical and molecular epidemiological data associated with intestinal protozoan infections among schoolchildren in Tripoli. A high prevalence of protozoan parasites was found, with Blastocystis spp. being the most predominant protozoans. Although only 50% of children reported digestive symptoms, asymptomatic infection was observed, and these children may act as unidentified carriers. This survey provides necessary information for designing prevention and control strategies to reduce the burden of these protozoan infections, especially in children.

Prevalence and Risk Factors for Intestinal Protozoan Infections with Cryptosporidium, Giardia, Blastocystis and Dientamoeba among Schoolchildren in Tripoli, Lebanon

PubMed Central

Benamrouz, Sadia; Nourrisson, Céline; Poirier, Philippe; Pereira, Bruno; Razakandrainibe, Romy; Pinon, Anthony; Lambert, Céline; Wawrzyniak, Ivan; Dabboussi, Fouad; Delbac, Frederic; Favennec, Loïc; Hamze, Monzer; Viscogliosi, Eric; Certad, Gabriela

2016-01-01

Background Intestinal protozoan infections are confirmed as major causes of diarrhea, particularly in children, and represent a significant, but often neglected, threat to public health. No recent data were available in Lebanon concerning the molecular epidemiology of protozoan infections in children, a vulnerable population at high risk of infection. Methodology and Principal Findings In order to improve our understanding of the epidemiology of intestinal pathogenic protozoa, a cross-sectional study was conducted in a general pediatric population including both symptomatic and asymptomatic subjects. After obtaining informed consent from the parents or legal guardians, stool samples were collected in January 2013 from 249 children in 2 schools in Tripoli, Lebanon. Information obtained from a standard questionnaire included demographic characteristics, current symptoms, socioeconomic status, source of drinking water, and personal hygiene habits. After fecal examination by both microscopy and molecular tools, the overall prevalence of parasitic infections was recorded as 85%. Blastocystis spp. presented the highest infection rate (63%), followed by Dientamoeba fragilis (60.6%), Giardia duodenalis (28.5%) and Cryptosporidium spp. (10.4%). PCR was also performed to identify species and genotypes of Cryptosporidium, subtypes of Blastocystis, and assemblages of Giardia. Statistical analysis using a logistic regression model showed that contact with family members presenting gastrointestinal disorders was the primary risk factor for transmission of these protozoa. Conclusions This is the first study performed in Lebanon reporting the prevalence and the clinical and molecular epidemiological data associated with intestinal protozoan infections among schoolchildren in Tripoli. A high prevalence of protozoan parasites was found, with Blastocystis spp. being the most predominant protozoans. Although only 50% of children reported digestive symptoms, asymptomatic infection was observed, and these children may act as unidentified carriers. This survey provides necessary information for designing prevention and control strategies to reduce the burden of these protozoan infections, especially in children. PMID:26974335

Cryptosporidium spp. and Giardia sp. in aquatic mammals in northern and northeastern Brazil.

PubMed

Borges, João Carlos; Lima, Danielle Dos; da Silva, Edson Moura; Moreira, André Lucas de Oliveira; Marmontel, Miriam; Carvalho, Vitor Luz; Amaral, Rodrigo de; Lazzarini, Stella Maris; Alves, Leucio Câmara

2017-09-20

Cryptosporidium and Giardia are protozoans that can infect humans and wild and domestic animals. Due to the growing importance of diseases caused by protozoan parasites in aquatic species, we aimed to evaluate the frequency of infection by Cryptosporidium spp. and Giardia sp. in aquatic and marine mammals in the northern and northeastern regions of Brazil. We collected 553 fecal samples from 15 species of wild-ranging and captive aquatic mammals in northern and northeastern Brazil. All samples were analyzed by the Kinyoun technique for identification of Cryptosporidium spp. oocysts. Giardia sp. cysts were identified by means of the centrifugal-flotation technique in zinc sulfate solution. Subsequently, all samples were submitted for direct immunofluorescence testing. The overall frequency of infection was 15.55% (86/553) for Cryptosporidium spp. and 9.04% (50/553) for Giardia sp. The presence of Cryptosporidium spp. was detected in samples from 5 species: neotropical river otter Lontra longicaudis (15.28%), giant otter Pteronura brasiliensis (41.66%), Guiana dolphin Sotalia guianensis (9.67%), Amazonian manatee Trichechus inunguis (16.03%), and Antillean manatee T. manatus (13.79%). Giardia sp. was identified in L. longicaudis (9.23%), P. brasiliensis (29.16%), pygmy sperm whale Kogia breviceps (100%), dwarf sperm whale K. sima (25%), S. guianensis (9.67%), T. inunguis (3.81%), and T. manatus (10.34%). This is the first report of Cryptosporidium spp. in L. longicaudis, P. brasiliensis, and S. guianensis, while the occurrence of Giardia sp., in addition to the 2 otter species, was also identified in manatees, thus extending the number of hosts susceptible to these parasitic agents.

Genotyping of Giardia isolates in Scotland: a descriptive epidemiological study.

PubMed

Alexander, C; Jones, B; Inverarity, D; Pollock, K G J

2014-08-01

Giardiasis, caused by the intestinal protozoan parasite Giardia intestinalis (synonyms: G. lamblia, G. duodenalis), is one of the most frequent parasites to infect the Scottish population. Transmission of the infective cysts in faecal matter is commonly via food and/or water. Giardia is subdivided into assemblages, where clinical and epidemiological differences have been described between assemblages A and B. This snapshot descriptive epidemiological study examines 30 positive cases of Giardia of which 72% (n = 21) were shown to be assemblage A, 14% (n = 4) assemblage B and 10% (n = 3) mixed assemblages (A and B). There was a 2:3 female:male ratio of affected individuals with foreign travel recorded in 22 of these cases. The commonest symptom was diarrhoea which was reported in 80% of cases followed by tiredness. Five cases required hospitalization emphasizing the importance of gaining a greater understanding of how Giardia assemblages influence clinical outcomes to assist in formulating guidelines to manage potential Giardia outbreaks.

The nucleotide sequence of the entire ribosomal DNA operon and the structure of the large subunit rRNA of Giardia muris.

PubMed

van Keulen, H; Gutell, R R; Campbell, S R; Erlandsen, S L; Jarroll, E L

1992-10-01

The total nucleotide sequence of the rDNA of Giardia muris, an intestinal protozoan parasite of rodents, has been determined. The repeat unit is 7668 basepairs (bp) in size and consists of a spacer of 3314 bp, a small-subunit rRNA (SSU-rRNA) gene of 1429, and a large-subunit rRNA (LSU-rRNA) gene of 2698 bp. The spacer contains long direct repeats and is heterogeneous in size. The LSU-rRNA of G. muris was compared to that of the human intestinal parasite Giardia duodenalis, to the bird parasite Giardia ardeae, and to that of Escherichia coli. The LSU-rRNA has a size comparable to the 23S rRNA of E. coli but shows structural features typical for eukaryotes. Some variable regions are typically small and account for the overall smaller size of this rRNA. The structure of the G. muris LSU-rRNA is similar to that of the other Giardia rRNA, but each rRNA has characteristic features residing in a number of variable regions.

Flagellar generated flow mediates attachment of Giardia Lamblia

NASA Astrophysics Data System (ADS)

Picou, Theodore; Polackwich, Jamie; Burrola Gabilondo, Beatriz; McAllister, Ryan; Powers, Tom; Elmendorf, Heidi; Urbach, Jeff

2011-11-01

Giardia lamblia is a protozoan parasite responsible for widespread diarrheal disease in humans and animals worldwide. Attachment to the host intestinal mucosa and resistance to peristalsis is necessary for establishing infection, but the physical basis for this attachment is poorly understood. We report results from confocal fluorescence microscopy that demonstrate that the regular beating of the posterior flagella generate a flow through the ventral disk, a suction-cup shaped structure that is against the substrate during attachment. Finite element simulations show that the negative pressure generated by the flow is consistent with the measured force of attachement between the parasite and its substrate.

DETECTION OF MICROSPORIDIA IN ENVIRONMENTAL WATERS

EPA Science Inventory

The health effects associated with various waterborne pathogenic microorganisms has been well documented. During the last quarter century protozoan parasites like Giardia and Cryptosporidium have been added to this group. To date, however, the causes of many cases of waterborne...

Molecular characterization of Cryptosporidium and Giardia from the Tasmanian devil (Sarcophilus harrisii).

PubMed

Wait, Liana F; Fox, Samantha; Peck, Sarah; Power, Michelle L

2017-01-01

The Tasmanian devil (Sarcophilus harrisii) is a carnivorous marsupial found only in the wild in Tasmania, Australia. Tasmanian devils are classified as endangered and are currently threatened by devil facial tumour disease, a lethal transmissible cancer that has decimated the wild population in Tasmania. To prevent extinction of Tasmanian devils, conservation management was implemented in 2003 under the Save the Tasmanian Devil Program. This study aimed to assess if conservation management was altering the interactions between Tasmanian devils and their parasites. Molecular tools were used to investigate the prevalence and diversity of two protozoan parasites, Cryptosporidium and Giardia, in Tasmanian devils. A comparison of parasite prevalence between wild and captive Tasmanian devils showed that both Cryptosporidium and Giardia were significantly more prevalent in wild devils (p < 0.05); Cryptosporidium was identified in 37.9% of wild devils but only 10.7% of captive devils, while Giardia was identified in 24.1% of wild devils but only 0.82% of captive devils. Molecular analysis identified the presence of novel genotypes of both Cryptosporidium and Giardia. The novel Cryptosporidium genotype was 98.1% similar at the 18S rDNA to Cryptosporidium varanii (syn. C. saurophilum) with additional samples identified as C. fayeri, C. muris, and C. galli. Two novel Giardia genotypes, TD genotype 1 and TD genotype 2, were similar to G. duodenalis from dogs (94.4%) and a Giardia assemblage A isolate from humans (86.9%). Giardia duodenalis BIV, a zoonotic genotype of Giardia, was also identified in a single captive Tasmanian devil. These findings suggest that conservation management may be altering host-parasite interactions in the Tasmanian devil, and the presence of G. duodenalis BIV in a captive devil points to possible human-devil parasite transmission.

Molecular characterization of Cryptosporidium and Giardia from the Tasmanian devil (Sarcophilus harrisii)

PubMed Central

Fox, Samantha; Peck, Sarah; Power, Michelle L.

2017-01-01

The Tasmanian devil (Sarcophilus harrisii) is a carnivorous marsupial found only in the wild in Tasmania, Australia. Tasmanian devils are classified as endangered and are currently threatened by devil facial tumour disease, a lethal transmissible cancer that has decimated the wild population in Tasmania. To prevent extinction of Tasmanian devils, conservation management was implemented in 2003 under the Save the Tasmanian Devil Program. This study aimed to assess if conservation management was altering the interactions between Tasmanian devils and their parasites. Molecular tools were used to investigate the prevalence and diversity of two protozoan parasites, Cryptosporidium and Giardia, in Tasmanian devils. A comparison of parasite prevalence between wild and captive Tasmanian devils showed that both Cryptosporidium and Giardia were significantly more prevalent in wild devils (p < 0.05); Cryptosporidium was identified in 37.9% of wild devils but only 10.7% of captive devils, while Giardia was identified in 24.1% of wild devils but only 0.82% of captive devils. Molecular analysis identified the presence of novel genotypes of both Cryptosporidium and Giardia. The novel Cryptosporidium genotype was 98.1% similar at the 18S rDNA to Cryptosporidium varanii (syn. C. saurophilum) with additional samples identified as C. fayeri, C. muris, and C. galli. Two novel Giardia genotypes, TD genotype 1 and TD genotype 2, were similar to G. duodenalis from dogs (94.4%) and a Giardia assemblage A isolate from humans (86.9%). Giardia duodenalis BIV, a zoonotic genotype of Giardia, was also identified in a single captive Tasmanian devil. These findings suggest that conservation management may be altering host-parasite interactions in the Tasmanian devil, and the presence of G. duodenalis BIV in a captive devil points to possible human-devil parasite transmission. PMID:28423030

INACTIVATION AND REMOVAL OF ENTERIC PROTOZOA IN WATER

EPA Science Inventory

Protozoan parasites including Giardia, Cryptosporidium, and Entamoeba can be transmitted through water and cause disease in humans and animals. Control of waterborne infection can be accomplished through a variety of physical and chemical means, resulting in the production of sa...

Anthropozoonotic Endoparasites in Free-Ranging "Urban" South American Sea Lions (Otaria flavescens).

PubMed

Hermosilla, Carlos; Silva, Liliana M R; Navarro, Mauricio; Taubert, Anja

2016-01-01

The present study represents the first report on the gastrointestinal endoparasite fauna of a free-ranging "urban" colony of South American sea lions (Otaria flavescens) living within the city of Valdivia, Chile. A total of 40 individual faecal samples of South American sea lions were collected during the year 2012 within their natural habitat along the river Calle-Calle and in the local fish market of Valdivia. Coprological analyses applying sodium acetate acetic formalin methanol (SAF) technique, carbol fuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen ELISAs, revealed infections with 8 different parasites belonging to protozoan and metazoan taxa with some of them bearing anthropozoonotic potential. Thus, five of these parasites were zoonotic (Diphyllobothriidae gen. sp., Anisakidae gen. sp., Giardia, Cryptosporidium, and Balantidium). Overall, these parasitological findings included four new parasite records for Otaria flavescens, that is, Giardia, Cryptosporidium, Balantidium, and Otostrongylus. The current data serve as a baseline for future monitoring studies on anthropozoonotic parasites circulating in these marine mammals and their potential impact on public health.

Prevalence, environmental loading, and molecular characterization of Cryptosporidium and Giardia

USGS Publications Warehouse

Oates, Stori C; Miller, Melissa A.; Hardin, Dane; Conrad, Patricia A.; Melli, Ann; Jessup, David A.; Dominik, Clare; Roug, Annette; Tinker, M. Tim; Miller, Woutrina A.

2012-01-01

The risk of disease transmission from waterborne protozoa is often dependent on the origin (e.g., domestic animals versus wildlife), overall parasite load in contaminated waterways, and parasite genotype, with infections being linked to runoff or direct deposition of domestic animal and wildlife feces. Fecal samples collected from domestic animals and wildlife along the central California coast were screened to (i) compare the prevalence and associated risk factors for fecal shedding of Cryptosporidium and Giardia species parasites, (ii) evaluate the relative importance of animal host groups that contribute to pathogen loading in coastal ecosystems, and (iii) characterize zoonotic and host-specific genotypes. Overall, 6% of fecal samples tested during 2007 to 2010 were positive for Cryptosporidium oocysts and 15% were positive for Giardia cysts. Animal host group and age class were significantly associated with detection of Cryptosporidium and Giardia parasites in animal feces. Fecal loading analysis revealed that infected beef cattle potentially contribute the greatest parasite load relative to other host groups, followed by wild canids. Beef cattle, however, shed host-specific, minimally zoonotic Cryptosporidium and Giardia duodenalis genotypes, whereas wild canids shed potentially zoonotic genotypes, including G. duodenalis assemblages A and B. Given that the parasite genotypes detected in cattle were not zoonotic, the public health risk posed by protozoan parasite shedding in cattle feces may be lower than that posed by other animals, such as wild canids, that routinely shed zoonotic genotypes.

Prevalence, environmental loading, and molecular characterization of Cryptosporidium and Giardia isolates from domestic and wild animals along the Central California Coast.

PubMed

Oates, Stori C; Miller, Melissa A; Hardin, Dane; Conrad, Patricia A; Melli, Ann; Jessup, David A; Dominik, Clare; Roug, Annette; Tinker, M Tim; Miller, Woutrina A

2012-12-01

The risk of disease transmission from waterborne protozoa is often dependent on the origin (e.g., domestic animals versus wildlife), overall parasite load in contaminated waterways, and parasite genotype, with infections being linked to runoff or direct deposition of domestic animal and wildlife feces. Fecal samples collected from domestic animals and wildlife along the central California coast were screened to (i) compare the prevalence and associated risk factors for fecal shedding of Cryptosporidium and Giardia species parasites, (ii) evaluate the relative importance of animal host groups that contribute to pathogen loading in coastal ecosystems, and (iii) characterize zoonotic and host-specific genotypes. Overall, 6% of fecal samples tested during 2007 to 2010 were positive for Cryptosporidium oocysts and 15% were positive for Giardia cysts. Animal host group and age class were significantly associated with detection of Cryptosporidium and Giardia parasites in animal feces. Fecal loading analysis revealed that infected beef cattle potentially contribute the greatest parasite load relative to other host groups, followed by wild canids. Beef cattle, however, shed host-specific, minimally zoonotic Cryptosporidium and Giardia duodenalis genotypes, whereas wild canids shed potentially zoonotic genotypes, including G. duodenalis assemblages A and B. Given that the parasite genotypes detected in cattle were not zoonotic, the public health risk posed by protozoan parasite shedding in cattle feces may be lower than that posed by other animals, such as wild canids, that routinely shed zoonotic genotypes.

Prevalence, Environmental Loading, and Molecular Characterization of Cryptosporidium and Giardia Isolates from Domestic and Wild Animals along the Central California Coast

PubMed Central

Miller, Melissa A.; Hardin, Dane; Conrad, Patricia A.; Melli, Ann; Jessup, David A.; Dominik, Clare; Roug, Annette; Tinker, M. Tim; Miller, Woutrina A.

2012-01-01

The risk of disease transmission from waterborne protozoa is often dependent on the origin (e.g., domestic animals versus wildlife), overall parasite load in contaminated waterways, and parasite genotype, with infections being linked to runoff or direct deposition of domestic animal and wildlife feces. Fecal samples collected from domestic animals and wildlife along the central California coast were screened to (i) compare the prevalence and associated risk factors for fecal shedding of Cryptosporidium and Giardia species parasites, (ii) evaluate the relative importance of animal host groups that contribute to pathogen loading in coastal ecosystems, and (iii) characterize zoonotic and host-specific genotypes. Overall, 6% of fecal samples tested during 2007 to 2010 were positive for Cryptosporidium oocysts and 15% were positive for Giardia cysts. Animal host group and age class were significantly associated with detection of Cryptosporidium and Giardia parasites in animal feces. Fecal loading analysis revealed that infected beef cattle potentially contribute the greatest parasite load relative to other host groups, followed by wild canids. Beef cattle, however, shed host-specific, minimally zoonotic Cryptosporidium and Giardia duodenalis genotypes, whereas wild canids shed potentially zoonotic genotypes, including G. duodenalis assemblages A and B. Given that the parasite genotypes detected in cattle were not zoonotic, the public health risk posed by protozoan parasite shedding in cattle feces may be lower than that posed by other animals, such as wild canids, that routinely shed zoonotic genotypes. PMID:23042185

Waterborne Pathogens: The Protozoans.

PubMed

Moss, Joseph Anthony

2016-09-01

Waterborne diseases associated with polluted recreational and potable waters have been documented for more than a century. Key microbial protozoan parasites, such as Cryptosporidium and Giardia, are causative agents for gastrointestinal disease worldwide. Although not a first-line diagnostic approach for these diseases, medical imaging, such as radiography, computed tomography, magnetic resonance imaging, ultrasonography, and nuclear medicine technologies, can be used to evaluate patients with long-term effects. This article describes protozoan pathogens that affect human health, treatment of common waterborne pathogen-related diseases, and associated medical imaging. ©2016 American Society of Radiologic Technologists.

Influence of land use and watershed characteristics on protozoa contamination in a potential drinking water resources reservoir.

PubMed

Keeley, Ann; Faulkner, Barton R

2008-05-01

Relative changes in the microbial quality of Lake Texoma, on the border of Texas and Oklahoma, were investigated by monitoring protozoan pathogens, fecal indicators, and factors influencing the intensity of the microbiological contamination of surface water reservoirs. The watershed serves rural agricultural communities active in cattle ranching, recreation, and is a potential drinking water source. A total of 193 surface water samples were tested over a 27-month period to determine levels of parasite contamination. The overall occurrence of Cryptosporidium oocysts was higher in both frequency and concentration than Giardia cysts. Cryptosporidium oocysts were found in 99% and Giardia cysts in 87% of the samples. Although Cryptosporidium and Giardia occurrence were significantly but not strongly correlated, all other correlation coefficients including turbidity and total dissolved solids were non-significant. Statistically supportable seasonal variations were found suggesting that Cryptosporidium and Giardia were higher in summer and fall than in other seasons of the year. While Cryptosporidium levels were correlated with rainfall, this was not the case with Giardia. The maximum numbers for both protozoan parasites were detected from a site impacted by cattle ranching during calving season. Restriction fragment length polymorphism analysis was used for confirmation of Cryptosporidium in surface waters influenced by agricultural discharges. As we had expected, oocysts were of the bovine type indicating that the Cryptosporidium parvum detected in surface waters perhaps came from cattle living in the watershed.

The past, present and future of fluorescent protein tags in anaerobic protozoan parasites.

PubMed

Morin-Adeline, Victoria; Šlapeta, Jan

2016-03-01

The world health organization currently recognizes diarrhoeal diseases as a significant cause of death in children globally. Protozoan parasites such as Giardia and Entamoeba that thrive in the oxygen-deprived environment of the human gut are common etiological agents of diarrhoea. In the urogenital tract of humans, the anaerobic protozoan parasite Trichomonas vaginalis is notorious as the most common non-viral, sexually transmitted pathogen. Even with high medical impact, our understanding of anaerobic parasite physiology is scarce and as a result, treatment choices are limited. Fluorescent proteins (FPs) are invaluable tools as genetically encoded protein tags for advancing knowledge of cellular function. These FP tags emit fluorescent colours and once attached to a protein of interest, allow tracking of parasite proteins in the dynamic cellular space. Application of green FPs-like FPs in anaerobic protozoans is hindered by their oxygen dependency. In this review, we examine aspects of anaerobic parasite biology that clash with physio-chemical properties of FPs and limit their use as live-parasite protein tags. We expose novel FPs, such as miniSOG that do not require oxygen for signal production. The potential use of novel FPs has the opportunity to leverage the anaerobe parasitologist toolkit to that of aerobe parasitologist.

Efficacy of New 5-Nitroimidazoles against Metronidazole-Susceptible and -Resistant Giardia, Trichomonas, and Entamoeba spp.

PubMed Central

Upcroft, Jacqueline A.; Campbell, Raymond W.; Benakli, Kamel; Upcroft, Peter; Vanelle, Patrice

1999-01-01

The efficacies of 12 5-nitroimidazole compounds and 1 previously described lactam-substituted nitroimidazole with antiparasitic activity, synthesized via SRN1 and subsequent reactions, were assayed against the protozoan parasites Giardia duodenalis, Trichomonas vaginalis, and Entamoeba histolytica. Two metronidazole-sensitive lines and two metronidazole-resistant lines of Giardia and one line each of metronidazole-sensitive and -resistant Trichomonas were tested. All except one of the compounds were as effective or more effective than metronidazole against Giardia and Trichomonas, but none was as effective overall as the previously described 2-lactam-substituted 5-nitroimidazole. None of the compounds was markedly more effective than metronidazole against Entamoeba. Significant cross-resistance between most of the drugs tested and metronidazole was evident among metronidazole-resistant lines of Giardia and Trichomonas. However, some drugs were lethal to metronidazole-resistant Giardia and had minimum lethal concentrations similar to that of metronidazole for drug-susceptible parasites. This study emphasizes the potential in developing new nitroimidazole drugs which are more effective than metronidazole and which may prove to be useful clinical alternatives to metronidazole. PMID:9869568

Effect of Mass Stool Examination and Mass Treatment For Decreasing Intestinal Helminth and Protozoan Infection Rates in Bolivian Children: A Cross-Sectional Study

PubMed Central

Còrdova Vidal, Claudia; Strauss, Wilma; Ikoma, Toshikazu; Endoh, Kazuo; Yamamoto, Masaharu

2016-01-01

Bolivia is one of the countries with a high intestinal helminth and protozoan infection rate. Despite the high prevalence of the parasitic infection, nationwide preventive measures for Bolivian children have not yet been implemented. We evaluated the effect of mass stool examination and treatment as a strategy for decreasing the infection rate. This study was conducted between 2013 and 2015 in children aged 2–18 years. A total of 2,033 stool samples (575 in 2013, 815 in 2014 and 642 in 2015) were collected and examined using the formalin-ether medical sedimentation method. As an anthelminthic medicine, nitazoxanide was given to all infected children within 2 months post-examination, each year. The effect of mass stool examination and treatment was evaluated based on the changes in the overall or individual parasitic infection rates during the study period. The overall parasitic infection rate decreased significantly from 65.2% in 2013 to 43.0% in 2015; a 22.2 percentage point decrease (P<0.001). Protozoan infection accounted for a large portion of the parasitic infections, in the following rates: 62.4% in 2013, 49.3% in 2014, and 41.0% in 2015. The rate of the most common helminth infection, Hymenolepis nana, decreased significantly from 9.0% in 2013 to 6.4% in 2014 to 3.4% in 2015 (P<0.001). Prevalence of the most common pathogenic protozoan infection, Entamoeba histolytica, decreased significantly from 19.0% in 2013 to 3.0% in 2015 (P<0.001). Conversely, the rate of Giardia intestinalis increased significantly from 16.5% in 2013 to 21.2% in 2015 (P<0.01). Mass stool examination and treatment for intestinal helminth and protozoan infections was effective for decreasing the overall parasitic infection rate in the study population, excluding Giardia intestinalis. Further studies on the long-term effect of mass stool examination and treatment for decreasing all intestinal parasitic infection rates in Bolivian children are needed. PMID:27923058

Cryptosporidium oocysts and giardia cysts on salad products irrigated with contaminated water.

PubMed

Amorós, Inmaculada; Alonso, José L; Cuesta, Gonzalo

2010-06-01

A field study in Valencia, Spain, was done to determine the occurrence of Giardia and Cryptosporidium on salad products that are frequently eaten raw, such as lettuces and Chinese cabbage, and in irrigation waters. Four water samples were taken weekly 1 month before harvesting the vegetables. All water samples were analyzed using techniques included in the U.S. Environmental Protection Agency Method 1623. Standard methods for detecting protozoan parasites on salad vegetables are not available. Published techniques for the isolation of parasites from vegetables generally have low and variable recovery efficiencies. In this study, vegetables were analyzed using a recently reported method for detection of Cryptosporidium oocysts and Giardia cysts on salad products. The waters tested were positive for both Cryptosporidium and Giardia. Of 19 salad products studied, we observed Cryptosporidium in 12 samples and Giardia in 10 samples. Recoveries of the Texas Red-stained Cryptosporidium and Giardia, which were used as internal controls, were 24.5% +/- 3.5% for Cryptosporidium and 16.7% +/- 8.1% for Giardia (n = 8). This study provides data on the occurrence of Cryptosporidium and Giardia in salad products in Spain. The method was useful in the detection of Cryptosporidium oocysts and Giardia cysts on the vegetables tested, and it provides a useful analytical tool for occurrence monitoring.

Giardia Alters Commensal Microbial Diversity throughout the Murine Gut

PubMed Central

Barash, N. R.; Maloney, J. G.

2017-01-01

ABSTRACT Giardia lamblia is the most frequently identified protozoan cause of intestinal infection. Over 200 million people are estimated to have acute or chronic giardiasis, with infection rates approaching 90% in areas where Giardia is endemic. Despite its significance in global health, the mechanisms of pathogenesis associated with giardiasis remain unclear, as the parasite neither produces a known toxin nor induces a robust inflammatory response. Giardia colonization and proliferation in the small intestine of the host may, however, disrupt the ecological homeostasis of gastrointestinal commensal microbes and contribute to diarrheal disease associated with giardiasis. To evaluate the impact of Giardia infection on the host microbiota, we used culture-independent methods to quantify shifts in the diversity of commensal microbes throughout the gastrointestinal tract in mice infected with Giardia. We discovered that Giardia's colonization of the small intestine causes a systemic dysbiosis of aerobic and anaerobic commensal bacteria. Specifically, Giardia colonization is typified by both expansions in aerobic Proteobacteria and decreases in anaerobic Firmicutes and Melainabacteria in the murine foregut and hindgut. Based on these shifts, we created a quantitative index of murine Giardia-induced microbial dysbiosis. This index increased at all gut regions during the duration of infection, including both the proximal small intestine and the colon. Giardiasis could be an ecological disease, and the observed dysbiosis may be mediated directly via the parasite's unique anaerobic fermentative metabolism or indirectly via parasite induction of gut inflammation. This systemic alteration of murine gut commensal diversity may be the cause or the consequence of inflammatory and metabolic changes throughout the gut. Shifts in the commensal microbiota may explain observed variations in giardiasis between hosts with respect to host pathology, degree of parasite colonization, infection initiation, and eventual clearance. PMID:28396324

Evaluation of multiplex tandem real-time PCR for detection of Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis in clinical stool samples.

PubMed

Stark, D; Al-Qassab, S E; Barratt, J L N; Stanley, K; Roberts, T; Marriott, D; Harkness, J; Ellis, J T

2011-01-01

The aim of this study was to describe the first development and evaluation of a multiplex tandem PCR (MT-PCR) assay for the detection and identification of 4 common pathogenic protozoan parasites, Cryptosporidium spp., Dientamoeba fragilis, Entamoeba histolytica, and Giardia intestinalis, from human clinical samples. A total of 472 fecal samples submitted to the Department of Microbiology at St. Vincent's Hospital were included in the study. The MT-PCR assay was compared to four real-time PCR (RT-PCR) assays and microscopy by a traditional modified iron hematoxylin stain. The MT-PCR detected 28 G. intestinalis, 26 D. fragilis, 11 E. histolytica, and 9 Cryptosporidium sp. isolates. Detection and identification of the fecal protozoa by MT-PCR demonstrated 100% correlation with the RT-PCR results, and compared to RT-PCR, MT-PCR exhibited 100% sensitivity and specificity, while traditional microscopy of stained fixed fecal smears exhibited sensitivities and specificities of 56% and 100% for Cryptosporidium spp., 38% and 99% for D. fragilis, 47% and 97% for E. histolytica, and 50% and 100% for G. intestinalis. No cross-reactivity was detected in 100 stool samples containing various other bacterial, viral, and protozoan species. The MT-PCR assay was able to provide rapid, sensitive, and specific simultaneous detection and identification of the four most important diarrhea-causing protozoan parasites that infect humans. This study also highlights the lack of sensitivity demonstrated by microscopy, and thus, molecular methods such as MT-PCR must be considered the diagnostic methods of choice for enteric protozoan parasites.

First report of predation of Giardia sp. cysts by ciliated protozoa and confirmation of predation of Cryptosporidium spp. oocysts by ciliate species.

PubMed

Siqueira-Castro, Isabel Cristina Vidal; Greinert-Goulart, Juliane Araújo; Bonatti, Tais Rondello; Yamashiro, Sandra; Franco, Regina Maura Bueno

2016-06-01

Ciliated protozoa are important components of the microbial food web in various habitats, especially aquatic environments. These organisms are useful bioindicators for both environmental quality assessment and the wastewater purification process. The pathogenic parasitic protozoan species Giardia and Cryptosporidium represent a significant concern for human health, being responsible for numerous disease outbreaks worldwide. The predation of cysts and oocysts in 15 ciliate species from water and sewage samples collected in Campinas, São Paulo, Brazil were verified under laboratory conditions. The ciliated protozoan species were selected based on their mode of nutrition, and only bacterivorous and suspension-feeders were considered for the experiments. The species Blepharisma sinuosum, Euplotes aediculatus, Sterkiella cavicola, Oxytricha granulifera, Vorticella infusionum, Spirostomum minus, and Stentor coeruleus ingested cysts and oocysts, the resistance forms of Giardia spp. and Cryptosporidium spp., respectively. This is the first time that the ingestion of Giardia cysts by ciliated protozoa has been reported. These findings may contribute to a better understanding of the biological removal of these pathogens from aquatic environments.

Characterization of the Giardia intestinalis secretome during interaction with human intestinal epithelial cells: The impact on host cells

PubMed Central

Ma’ayeh, Showgy Y.; Liu, Jingyi; Peirasmaki, Dimitra; Hörnaeus, Katarina; Bergström Lind, Sara; Grabherr, Manfred; Bergquist, Jonas

2017-01-01

Background Giardia intestinalis is a non-invasive protozoan parasite that causes giardiasis in humans, the most common form of parasite-induced diarrhea. Disease mechanisms are not completely defined and very few virulence factors are known. Methodology To identify putative virulence factors and elucidate mechanistic pathways leading to disease, we have used proteomics to identify the major excretory-secretory products (ESPs) when Giardia trophozoites of WB and GS isolates (assemblages A and B, respectively) interact with intestinal epithelial cells (IECs) in vitro. Findings The main parts of the IEC and parasite secretomes are constitutively released proteins, the majority of which are associated with metabolism but several proteins are released in response to their interaction (87 and 41 WB and GS proteins, respectively, 76 and 45 human proteins in response to the respective isolates). In parasitized IECs, the secretome profile indicated effects on the cell actin cytoskeleton and the induction of immune responses whereas that of Giardia showed anti-oxidation, proteolysis (protease-associated) and induction of encystation responses. The Giardia secretome also contained immunodominant and glycosylated proteins as well as new candidate virulence factors and assemblage-specific differences were identified. A minor part of Giardia ESPs had signal peptides (29% for both isolates) and extracellular vesicles were detected in the ESPs fractions, suggesting alternative secretory pathways. Microscopic analyses showed ESPs binding to IECs and partial internalization. Parasite ESPs reduced ERK1/2 and P38 phosphorylation and NF-κB nuclear translocation. Giardia ESPs altered gene expression in IECs, with a transcriptional profile indicating recruitment of immune cells via chemokines, disturbances in glucose homeostasis, cholesterol and lipid metabolism, cell cycle and induction of apoptosis. Conclusions This is the first study identifying Giardia ESPs and evaluating their effects on IECs. It highlights the importance of host and parasite ESPs during interactions and reveals the intricate cellular responses that can explain disease mechanisms and attenuated inflammatory responses during giardiasis. PMID:29228011

Prevalence of intestinal parasites in private-household cats in Japan.

PubMed

Itoh, Naoyuki; Ikegami, Hiroshi; Takagi, Masahiro; Ito, Yoichi; Kanai, Kazutaka; Chikazawa, Seishiro; Hori, Yasutomo; Hoshi, Fumio; Higuchi, Seiichi

2012-06-01

The present study is the first national investigation of intestinal parasites in private-household cats in Japan. A total of 942 faecal samples were collected from private-household cats. Giardia species was assessed using an enzyme-linked immunosorbent assay kit and other intestinal parasites were identified microscopically. The overall prevalence of intestinal parasites was 10.1%; two protozoan parasites (Giardia species and Cystoisospora species) and five helminths (Toxocara cati, Toxascaris leonina, Ancylostoma tubaeforme, Taenia species and Spirometra erinacei) were detected. The total prevalence of intestinal parasite infection was significantly higher in cats aged ≤ 6 months old than in cats older than 6 months because of a significantly higher prevalence of Cystoisospora species and T cati. The total infection prevalence was higher among outdoor cats as a result of the significantly higher prevalence of T cati and S erinacei. Sex and faecal condition were not related to intestinal parasite infections. Regional differences were observed in Cystoisospora species and A tubaeforme.

Anthropozoonotic Endoparasites in Free-Ranging “Urban” South American Sea Lions (Otaria flavescens)

PubMed Central

Silva, Liliana M. R.; Navarro, Mauricio; Taubert, Anja

2016-01-01

The present study represents the first report on the gastrointestinal endoparasite fauna of a free-ranging “urban” colony of South American sea lions (Otaria flavescens) living within the city of Valdivia, Chile. A total of 40 individual faecal samples of South American sea lions were collected during the year 2012 within their natural habitat along the river Calle-Calle and in the local fish market of Valdivia. Coprological analyses applying sodium acetate acetic formalin methanol (SAF) technique, carbol fuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen ELISAs, revealed infections with 8 different parasites belonging to protozoan and metazoan taxa with some of them bearing anthropozoonotic potential. Thus, five of these parasites were zoonotic (Diphyllobothriidae gen. sp., Anisakidae gen. sp., Giardia, Cryptosporidium, and Balantidium). Overall, these parasitological findings included four new parasite records for Otaria flavescens, that is, Giardia, Cryptosporidium, Balantidium, and Otostrongylus. The current data serve as a baseline for future monitoring studies on anthropozoonotic parasites circulating in these marine mammals and their potential impact on public health. PMID:27051860

Intestinal parasitism in the United States: update on a continuing problem.

PubMed

Kappus, K D; Lundgren, R G; Juranek, D D; Roberts, J M; Spencer, H C

1994-06-01

To document patterns of intestinal parasitism in the United States, we analyzed results of 216,275 stool specimens examined by the state diagnostic laboratories in 1987; parasites were found in 20.0%. Percentages were highest for protozoans: Giardia lamblia (7.2%), Entamoeba coli and Endolimax nana (4.2% each), Blastocystis hominis (2.6%), and Entamoeba histolytica (0.9%). The most commonly identified helminths were nematodes: hookworm (1.5%), Trichuris trichiura (1.2%), and Ascaris lumbricoides (0.8%). Identifications of G. lamblia increased broadly from the 4.0% average found in 1979, with 40 states reporting increases and seven reporting decreases. Seasonally, Giardia identifications increased in the summer and fall, especially in the Midwest. Nine states reported hookworms in more than 2% of specimens; none were states with indigenous transmission. We analyzed similar, but abbreviated, data for 1991; parasites were found in 19.7% of the 178,786 specimens and Giardia was found in 5.6%. States reporting percentages of Giardia identification in the highest quartile for both 1987 and 1991 were located in the Midwest or in the Northwest. Cryptosporidium was identified in both the 1987 and 1991 surveys; it had not been identified in a previous survey. For each year, Cryptosporidium was reported from 25 states across the country (for both years in 17 states). We conclude that intestinal parasitism should not be overlooked as a cause of gastrointestinal illness in the United States and that the prevalence of Giardia may be increasing.

A new species of Giardia Künstler, 1882 (Sarcomastigophora: Hexamitidae) in hamsters.

PubMed

Lyu, Zhangxia; Shao, Jingru; Xue, Min; Ye, Qingqing; Chen, Bing; Qin, Yan; Wen, Jianfan

2018-03-20

Giardia spp. are flagellated protozoan parasites that infect humans and many other vertebrates worldwide. Currently seven species of Giardia are considered valid. Here, we report a new species, Giardia cricetidarum n. sp. in hamsters. Trophozoites of G. cricetidarum n. sp. are pear-shaped with four pairs of flagella and measure on average 14 μm (range 12-18 μm) in length and 10 μm (range 8-12 μm) in width. The trophozoites of the new species are generally larger and stouter than those of most of the other Giardia spp. and exhibit the lowest length/width ratio (c.1.40) of all recognized Giardia species. Cysts of G. cricetidarum n. sp. are ovoid and measure on average 11 μm (range 9-12 μm) in length and 10 μm (range 8-10 μm) in width and are indistinguishable from the cysts of other Giardia species. Molecular phylogenetic analyses based on beta-giardin, small subunit rRNA, and elongation factor-1 alpha loci all demonstrated that G. cricetidarum n. sp. is genetically distinct from all currently accepted Giardia spp. Investigation of the host range indicated that the new species was only found in hamsters (including Phodopus sungorus, P. campbelli and Mesocricetus auratus), while all the other described mammal-parasitizing species (G. muris, G. microti and G. intestinalis) each infect multiple hosts. Cross-transmission studies further demonstrated the apparent host specificity of G. cricetidarum n. sp. as it only infected hamsters. Trophozoites were found in high numbers in hamster intestines (5 × 10 5 - 5 × 10 6 ) and was rarely detected co-infecting with other Giardia spp. in the common hamster, suggesting it has some advantages in parasitizing hamsters. This study has identified a new species of Giardia, which appears to be specific to hamsters, and together with the three other mammal-parasitizing Giardia species with different host ranges, may be able to be used as a model system for the study of evolutionary divergence of host parasitism strategies in Giardia.

Highly sensitive and specific detection of Giardia duodenalis, Entamoeba histolytica, and Cryptosporidium spp. in human stool samples by the BD MAX™ Enteric Parasite Panel.

PubMed

Parčina, Marijo; Reiter-Owona, Ingrid; Mockenhaupt, Frank P; Vojvoda, Valerija; Gahutu, Jean Bosco; Hoerauf, Achim; Ignatius, Ralf

2018-02-01

Detection of intestinal protozoan parasites by light microscopy is cumbersome, needs experienced personnel, and may lack sensitivity and/or specificity as compared with molecular-based stool assays. Here, we evaluated the BD MAX™ Enteric Parasite Panel, i.e., a multiplex real-time PCR assay for simultaneous detection of Giardia duodenalis, Entamoeba histolytica, and cryptosporidia (Cryptosporidium parvum and C. hominis), by examining 200 positive human stool samples (138 × G. duodenalis, 27 × E. histolytica, 35 × Cryptosporidium spp.) and 119 controls including 18 samples with E. dispar. The majority of the samples, i.e., 153/200 (76.5%) positive samples and 66/119 (55.5%) controls, were confirmed by multiplex in-house PCR detecting the same parasites as the BD MAX™ Enteric Parasite Panel. The BD MAX™ assay did not yield false-positive results. Sensitivity and specificity were 97.8% (95% CI, 93.3-99.4%) and 100% (95% CI, 97.4-100%) for G. duodenalis, 100% (95% CI, 84.5-100%) and 100% (95% CI, 98.4-100%) for E. histolytica, and 100% (95% CI, 87.7-100%) and 100% (95% CI, 98.3-100%) for cryptosporidia, and similar data were obtained when only the 219 PCR-confirmed samples were analyzed. Thus, the BD MAX™ Enteric Parasite Panel provides a highly sensitive and specific tool for the laboratory diagnosis of three predominant protozoan parasites causing enteritis.

Performance of microscopy and ELISA for diagnosing Giardia duodenalis infection in different pediatric groups.

PubMed

Silva, Renata K N R; Pacheco, Flávia T F; Martins, Adson S; Menezes, Joelma F; Costa-Ribeiro, Hugo; Ribeiro, Tereza C M; Mattos, Ângela P; Oliveira, Ricardo R; Soares, Neci M; Teixeira, Márcia C A

2016-12-01

Techniques for Giardia diagnosis based on microscopy are usually applied as routine laboratory testing; however, they typically exhibit low sensitivity. This study aimed to evaluate Giardia duodenalis and other intestinal parasitic infections in different pediatric groups, with an emphasis on the comparison of Giardia diagnostic techniques. Feces from 824 children from different groups (diarrheic, malnourished, with cancer and from day care) were examined by microscopy and ELISA for Giardia, Cryptosporidium sp. and Entamoeba histolytica coproantigen detection. Giardia-positive samples from day-care children, identified by either microscopy or ELISA, were further tested by PCR targeting of the β-giardin and Gdh genes. Statistically significant differences (P<0.05) were observed when comparing the frequency of each protozoan among the groups. Giardia duodenalis was more frequent in day-care children and Cryptosporidium sp. in diarrheic and malnourished groups; infections by Entamoeba histolytica were found only in children with diarrhea. Considering positivity for Giardia by at least one method, ELISA was found to be more sensitive than microscopy (97% versus 55%). To examine discrepancies among the diagnostic methods, 71 Giardia-positive stool samples from day-care children were tested by PCR; of these, DNA was amplified from 51 samples (77.4%). Concordance of positivity between microscopy and ELISA was found for 48 samples, with 43 confirmed by PCR. Parasite DNA was amplified from eleven of the 20 Giardia samples (55%) identified only by ELISA. This study shows the higher sensitivity of ELISA over microscopy for Giardia diagnosis when a single sample is analyzed and emphasizes the need for methods based on coproantigen detection to identify this parasite in diarrheic fecal samples. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Detection of Giardia intestinalis in water samples collected from natural water reservoirs and wells in northern and north-eastern Poland using LAMP, real-time PCR and nested PCR.

PubMed

Lass, Anna; Szostakowska, Beata; Korzeniewski, Krzysztof; Karanis, Panagiotis

2017-10-01

Giardia intestinalis is a protozoan parasite, transmitted to humans and animals by the faecal-oral route, mainly through contaminated water and food. Knowledge about the distribution of this parasite in surface water in Poland is fragmentary and incomplete. Accordingly, 36 environmental water samples taken from surface water reservoirs and wells were collected in Pomerania and Warmia-Masuria provinces, Poland. The 50 L samples were filtered and subsequently analysed with three molecular detection methods: loop-mediated isothermal amplification (LAMP), real-time polymerase chain reaction (real-time PCR) and nested PCR. Of the samples examined, Giardia DNA was found in 15 (42%) samples with the use of LAMP; in 12 (33%) of these samples, Giardia DNA from this parasite was also detected using real-time PCR; and in 9 (25%) using nested PCR. Sequencing of selected positive samples confirmed that the PCR products were fragments of the Giardia intestinalis small subunit rRNA gene. Genotyping using multiplex real-time PCR indicated the presence of assemblages A and B, with the latter predominating. The results indicate that surface water in Poland, as well as water taken from surface wells, may be a source of Giardia strains which are potentially pathogenic for humans. It was also demonstrated that LAMP assay is more sensitive than the other two molecular assays.

Protozoan and helminth parasite fauna of free-living Croatian wild wolves (Canis lupus) analyzed by scat collection.

PubMed

Hermosilla, Carlos; Kleinertz, Sonja; Silva, Liliana M R; Hirzmann, Jörg; Huber, Djuro; Kusak, Josip; Taubert, Anja

2017-01-15

The European wolf (Canis lupus) is a large carnivore species present in limited areas of Europe with several small populations still being considered as endangered. Wolves can be infected by a wide range of protozoan and metazoan parasites with some of them affecting free-living wolf health condition. On this account, an epidemiological survey was conducted to analyze the actual parasite fauna in Croatian wild wolves. In total, 400 individual faecal samples were collected during field studies on wolf ecology in the years 2002-2011. Parasite stages were identified by the sodium acetate acetic acid formalin (SAF)-technique, carbolfuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen-ELISAs. A subset of taeniid eggs-positive wolf samples was additionally analyzed by PCR and subsequent sequencing to identify eggs on Echinococcus granulosus/E. multilocularis species level. In total 18 taxa of parasites were here detected. Sarcocystis spp. (19.1%) occurred most frequently in faecal samples, being followed by Capillaria spp. (16%), ancylostomatids (13.1%), Crenosoma vulpis (4.6%), Angiostrongylus vasorum (3.1%), Toxocara canis (2.8%), Hammondia/Neospora spp. (2.6 %), Cystoisospora ohioensis (2.1%), Giardia spp. (2.1%), Cystoisospora canis (1.8%), Cryptosporidium spp. (1.8%), Trichuris vulpis (1.5%), Taenia spp. (1.5%), Diphyllobothrium latum (1.5%), Strongyloides spp. (0.5%), Opisthorchis felineus (0.5%), Toxascaris leonina (0.3%), Mesocestoides litteratus (0.3%) and Alaria alata (0.3%). Some of the here identified parasites represent relevant pathogens for wolves, circulating between these carnivorous definitive hosts and a variety of mammalian intermediate hosts, e. g. Taenia spp. and Sarcocystis spp., while others are considered exclusively pathogenic for canids (e.g. A. vasorum, C. vulpis, T. vulpis, Cystoisospora spp.). This study provides first records on the occurrence of the two relevant anthropozoonotic parasites, Giardia spp. and Cryptosporidium spp., in wild wolves from Croatia. Copyright © 2016 Elsevier B.V. All rights reserved.

Interactions of Giardia sp. with the intestinal barrier: Epithelium, mucus, and microbiota

PubMed Central

Amat, Christina B.; Buret, André G.

2017-01-01

ABSTRACT Understanding how intestinal enteropathogens cause acute and chronic alterations has direct animal and human health perspectives. Significant advances have been made on this field by studies focusing on the dynamic crosstalk between the intestinal protozoan parasite model Giardia duodenalis and the host intestinal mucosa. The concept of intestinal barrier function is of the highest importance in the context of many gastrointestinal diseases such as infectious enteritis, inflammatory bowel disease, and post-infectious gastrointestinal disorders. This crucial function relies on 3 biotic and abiotic components, first the commensal microbiota organized as a biofilm, then an overlaying mucus layer, and finally the tightly structured intestinal epithelium. Herein we review multiple strategies used by Giardia parasite to circumvent these 3 components. We will summarize what is known and discuss preliminary observations suggesting how such enteropathogen directly and/ or indirectly impairs commensal microbiota biofilm architecture, disrupts mucus layer and damages host epithelium physiology and survival. PMID:28452685

Dysfunctions at human intestinal barrier by water-borne protozoan parasites: lessons from cultured human fully differentiated colon cancer cell lines.

PubMed

Liévin-Le Moal, Vanessa

2013-06-01

Some water-borne protozoan parasites induce diseases through their membrane-associated functional structures and virulence factors that hijack the host cellular molecules and signalling pathways leading to structural and functional lesions in the intestinal barrier. In this Microreview we analyse the insights on the mechanisms of pathogenesis of Entamoeba intestinalis, Giardia and Cryptosporidium observed in the human colon carcinoma fully differentiated colon cancer cell lines, cell subpopulations and clones expressing the structural and functional characteristics of highly specialized fully differentiated epithelial cells lining the intestinal epithelium and mimicking structurally and functionally an intestinal barrier. © 2013 John Wiley & Sons Ltd.

Breast-feeding protects infantile diarrhea caused by intestinal protozoan infections.

PubMed

Abdel-Hafeez, Ekhlas Hamed; Belal, Usama Salah; Abdellatif, Manal Zaki Mohamed; Naoi, Koji; Norose, Kazumi

2013-10-01

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-α were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-α were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-α and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.

Giardia secretome highlights secreted tenascins as a key component of pathogenesis

PubMed Central

Dubourg, Audrey; Xia, Dong; Winpenny, John P; Al Naimi, Suha; Bouzid, Maha; Sexton, Darren W; Wastling, Jonathan M; Hunter, Paul R; Tyler, Kevin M

2018-01-01

Abstract Background Giardia is a protozoan parasite of public health relevance that causes gastroenteritis in a wide range of hosts. Two genetically distinct lineages (assemblages A and B) are responsible for the human disease. Although it is clear that differences in virulence occur, the pathogenesis and virulence of Giardia remain poorly understood. Results The genome of Giardia is believed to contain open reading frames that could encode as many as 6000 proteins. By successfully applying quantitative proteomic analyses to the whole parasite and to the supernatants derived from parasite culture of assemblages A and B, we confirm expression of ∼1600 proteins from each assemblage, the vast majority of which are common to both lineages. To look for signature enrichment of secreted proteins, we considered the ratio of proteins in the supernatant compared with the pellet, which defined a small group of enriched proteins, putatively secreted at a steady state by cultured growing trophozoites of both assemblages. This secretome is enriched with proteins annotated to have N-terminal signal peptide. The most abundant secreted proteins include known virulence factors such as cathepsin B cysteine proteases and members of a Giardia superfamily of cysteine-rich proteins that comprise variant surface proteins, high-cysteine membrane proteins, and a new class of virulence factors, the Giardia tenascins. We demonstrate that physiological function of human enteric epithelial cells is disrupted by such soluble factors even in the absence of the trophozoites. Conclusions We are able to propose a straightforward model of Giardia pathogenesis incorporating key roles for the major Giardia-derived soluble mediators. PMID:29385462

Giardia secretome highlights secreted tenascins as a key component of pathogenesis.

PubMed

Dubourg, Audrey; Xia, Dong; Winpenny, John P; Al Naimi, Suha; Bouzid, Maha; Sexton, Darren W; Wastling, Jonathan M; Hunter, Paul R; Tyler, Kevin M

2018-03-01

Giardia is a protozoan parasite of public health relevance that causes gastroenteritis in a wide range of hosts. Two genetically distinct lineages (assemblages A and B) are responsible for the human disease. Although it is clear that differences in virulence occur, the pathogenesis and virulence of Giardia remain poorly understood. The genome of Giardia is believed to contain open reading frames that could encode as many as 6000 proteins. By successfully applying quantitative proteomic analyses to the whole parasite and to the supernatants derived from parasite culture of assemblages A and B, we confirm expression of ∼1600 proteins from each assemblage, the vast majority of which are common to both lineages. To look for signature enrichment of secreted proteins, we considered the ratio of proteins in the supernatant compared with the pellet, which defined a small group of enriched proteins, putatively secreted at a steady state by cultured growing trophozoites of both assemblages. This secretome is enriched with proteins annotated to have N-terminal signal peptide. The most abundant secreted proteins include known virulence factors such as cathepsin B cysteine proteases and members of a Giardia superfamily of cysteine-rich proteins that comprise variant surface proteins, high-cysteine membrane proteins, and a new class of virulence factors, the Giardia tenascins. We demonstrate that physiological function of human enteric epithelial cells is disrupted by such soluble factors even in the absence of the trophozoites. We are able to propose a straightforward model of Giardia pathogenesis incorporating key roles for the major Giardia-derived soluble mediators.

Gastrointestinal parasites of the colobus monkeys of Uganda.

PubMed

Gillespie, Thomas R; Greiner, Ellis C; Chapman, Colin A

2005-06-01

From August 1997 to July 2003, we collected 2,103 fecal samples from free-ranging individuals of the 3 colobus monkey species of Uganda-the endangered red colobus (Piliocolobus tephrosceles), the eastern black-and-white colobus (Colobus guereza), and the Angolan black-and-white colobus (C. angolensis)--to identify and determine the prevalence of gastrointestinal parasites. Helminth eggs, larvae, and protozoan cysts were isolated by sodium nitrate flotation and fecal sedimentation. Coprocultures facilitated identification of helminths. Seven nematodes (Strongyloides fulleborni, S. stercoralis, Oesophagostomum sp., an unidentified strongyle, Trichuris sp., Ascaris sp., and Colobenterobius sp.), 1 cestode (Bertiella sp.), 1 trematode (Dicrocoeliidae), and 3 protozoans (Entamoeba coli, E. histolytica, and Giardia lamblia) were detected. Seasonal patterns of infection were not apparent for any parasite species infecting colobus monkeys. Prevalence of S. fulleborni was higher in adult male compared to adult female red colobus, but prevalence did not differ for any other shared parasite species between age and sex classes.

Assessing the burden of intestinal parasites affecting newly arrived immigrants in Qatar.

PubMed

Abu-Madi, Marawan A; Behnke, Jerzy M; Ismail, Ahmed; Boughattas, Sonia

2016-12-01

In the last decades, the enormous influx of immigrants to industrialized countries has led to outbreaks of parasitic diseases, with enteric infections being amongst the most frequently encountered. In its strategy to control such infection, Qatar has established the Pre-Employment Certificate (PEC) program which requires medical inspection before arrival in Qatar and which is mandatory for immigrant workers travelling to the country. To assess the reliability of the PEC, we conducted a survey of intestinal parasites, based on examination of stool samples provided by immigrant workers (n = 2,486) recently arrived in Qatar. Overall prevalence of helminths was 7.0% and that of protozoa was 11.7%. Prevalence of combined helminths was highest among the western Asians and the highest prevalence of combined protozoan parasites was among workers from North to Saharan Africa. Analysis of temporal changes showed an increasing trend of protozoan infections over the investigated 3 years. A major contribution to this temporal change in prevalence came from Blastocystis hominis as well as from other protozoan species: Giardia duodenalis and Endolimax nana. Analysis of the temporal trend in species richness of the protozoan species showed a significant increase in the mean number of species harboured per subject across this period. The increase of protozoan infections over recent years raises some concerns. It suggests that screening protocols for applicants for visas/work permits needs to be revised giving more careful attention to the intestinal protozoan infections that potential immigrants may harbor.

An up-date on Giardia and giardiasis.

PubMed

Einarsson, Elin; Ma'ayeh, Showgy; Svärd, Staffan G

2016-12-01

Giardia intestinalis is a non-invasive protozoan parasite infecting the upper small intestine causing acute, watery diarrhea or giardiasis in 280 million people annually. Asymptomatic infections are equally common and recent data have suggested that infections even can be protective against other diarrheal diseases. Most symptomatic infections resolve spontaneously but infections can lead to chronic disease and treatment failures are becoming more common world-wide. Giardia infections can also result in irritable bowel syndrome (IBS) and food allergies after resolution. Until recently not much was known about the mechanism of giardiasis or the cause of post-giardiasis syndromes and treatment failures, but here we will describe the recent progress in these areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

Occurrence and distribution of Giardia species in wild rodents in Germany.

PubMed

Helmy, Yosra A; Spierling, Nastasja G; Schmidt, Sabrina; Rosenfeld, Ulrike M; Reil, Daniela; Imholt, Christian; Jacob, Jens; Ulrich, Rainer G; Aebischer, Toni; Klotz, Christian

2018-03-27

Giardiasis is an important gastrointestinal parasitic disease in humans and other mammals caused by the protozoan Giardia duodenalis. This species complex is represented by genetically distinct groups (assemblages A-H) with varying zoonotic potential and host preferences. Wild rodents can harbor potentially zoonotic assemblages A and B, and the rodent-specific assemblage G. Other Giardia spp. found in these animals are Giardia muris and Giardia microti. For the latter, only limited information on genetic typing is available. It has been speculated that wild rodents might represent an important reservoir for parasites causing human giardiasis. The aim of this study was to investigate the occurrence and distribution of Giardia spp. and assemblage types in wild rodents from different study sites in Germany. Screening of 577 wild rodents of the genera Apodemus, Microtus and Myodes, sampled at eleven study sites in Germany, revealed a high overall Giardia prevalence. Giardia species determination at the SSU rDNA gene locus revealed that Apodemus mice, depending on species, were predominantly infected with one of two distinct G. muris sequence types. Giardia microti was the predominant parasite species found in voles of the genera Microtus and Myodes. Only a few animals were positive for potentially zoonotic G. duodenalis. Subtyping at the beta-giardin (bg) and glutamine dehydrogenase (gdh) genes strongly supported the existence of different phylogenetic subgroups of G. microti that are preferentially harbored by distinct host species. The present study highlights the preference of G. muris for Apodemus, and G. microti for Microtus and Myodes hosts and argues for a very low prevalence of zoonotic G. duodenalis assemblages in wild rodents in Germany. It also provides evidence that G. muris and G. microti subdivide into several phylogenetically distinguishable subgroups, each of which appears to be preferentially harbored by species of a particular rodent host genus. Finally, the study expands the database of sequences relevant for sequence typing of G. muris and G. microti isolates which will greatly help future analyses of these parasites' population structure.

Occurrence of Cryptosporidium and Giardia and the Relationship between Protozoa and Water Quality Indicators in Swimming Pools.

PubMed

Xiao, Shumin; Yin, Pengna; Zhang, Yan; Hu, Sike

2017-04-01

A total of 60 samples were collected from 35 swimming pools in Beijing, China, and the presence of Cryptosporidium and Giardia were investigated. The results showed that 16.7% and 15.0% of samples were positive for Cryptosporidium oocyst and Giardia cysts, respectively, with a mean concentration of 0.30 oocysts/10 L and 0.27 cysts/10 L. The oocysts and cysts were found to have higher rates of occurrence in August than in May. Genotyping confirmed the presence of Cryptosporidium hominis, C. parvum , and Giardia assemblages A and B, all of which were associated with human infections. The predominant species/assemblages were C. hominis and Giardia assemblage A. Analyses of the relationships between parasite oocysts/cysts, indicator bacteria, and physical-chemical parameters revealed that there was no correlation between 2 parasites and fecal bacterial indicators, whilst there was a significant correlation between protozoa and urea concentration, which indicates that urea concentration rather than fecal bacterial indicators might be an appropriate index for chlorine-resistant protozoa in swimming pools. This study provides useful information to improve the safety of swimming pool water and deduce the risk of protozoan infections.

Nuclear inheritance and genetic exchange without meiosis in the binucleate parasite Giardia intestinalis

PubMed Central

Carpenter, Meredith L.; Assaf, Zoe June; Gourguechon, Stéphane; Cande, W. Zacheus

2012-01-01

The protozoan parasite Giardia intestinalis (also known as Giardia lamblia) is a major waterborne pathogen. During its life cycle, Giardia alternates between the actively growing trophozoite, which has two diploid nuclei with low levels of allelic heterozygosity, and the infectious cyst, which has four nuclei and a tough outer wall. Although the formation of the cyst wall has been studied extensively, we still lack basic knowledge about many fundamental aspects of the cyst, including the sources of the four nuclei and their distribution during the transformation from cyst into trophozoite. In this study, we tracked the identities of the nuclei in the trophozoite and cyst using integrated nuclear markers and immunofluorescence staining. We demonstrate that the cyst is formed from a single trophozoite by a mitotic division without cytokinesis and not by the fusion of two trophozoites. During excystation, the cell completes cytokinesis to form two daughter trophozoites. The non-identical nuclear pairs derived from the parent trophozoite remain associated in the cyst and are distributed to daughter cells during excystation as pairs. Thus, nuclear sorting (such that each daughter cell receives a pair of identical nuclei) does not appear to be a mechanism by which Giardia reduces heterozygosity between its nuclei. Rather, we show that the cyst nuclei exchange chromosomal genetic material, perhaps as a way to reduce heterozygosity in the absence of meiosis and sex, which have not been described in Giardia. These results shed light on fundamental aspects of the Giardia life cycle and have implications for our understanding of the population genetics and cell biology of this binucleate parasite. PMID:22366460

Microfluidics for effective concentration and sorting of waterborne protozoan pathogens.

PubMed

Jimenez, M; Bridle, H

2016-07-01

We report on an inertial focussing based microfluidics technology for concentrating waterborne protozoa, achieving a 96% recovery rate of Cryptosporidium parvum and 86% for Giardia lamblia at a throughput (mL/min) capable of replacing centrifugation. The approach can easily be extended to other parasites and also bacteria. Copyright © 2016 Elsevier B.V. All rights reserved.

Lectin-Magnetic Separation (LMS) for isolation of Toxoplasma gondii oocysts from concentrated water samples prior to detection by microscopy or qPCR

USDA-ARS?s Scientific Manuscript database

Although standard methods for analyzing water samples for the protozoan parasites Cryptosporidium spp. and Giardia duodenalis are available and widely used, equivalent methods for analyzing water samples for Toxoplasma oocysts are lacking. This is partly due to the lack of a readily available, relia...

Non-biting cyclorrhaphan flies (Diptera) as carriers of intestinal human parasites in slum areas of Addis Ababa, Ethiopia.

PubMed

Getachew, Sisay; Gebre-Michael, Teshome; Erko, Berhanu; Balkew, Meshesha; Medhin, Girmay

2007-09-01

A study was conducted to determine the role of non-biting cyclorrhaphan flies as carriers of intestinal parasites in slum areas of Addis Ababa from January 2004 to June 2004. A total of 9550 flies, comprising of at least seven species were collected from four selected sites and examined for human intestinal parasites using the formol-ether concentration method. The dominant fly species was Chrysomya rufifacies (34.9%) followed by Musca domestica (31%), Musca sorbens (20.5.%), Lucina cuprina (6.8%), Sarcophaga sp. (2.8%), Calliphora vicina (2.2%) and Wohlfahrtia sp. (1.8%). Six intestinal helminths (Ascaris lumbricoides, Trichuris trichiura, hookworms, Hymenolepis nana, Taenia spp. and Strongyloides stercoralis) and at least four protozoan parasites (Entamoeba histolytica/dispar, Entamoeba coli, Giardia lamblia and Cryptosporidium sp.) were isolated from both the external and gut contents of the flies. A. lumbricoides and T. trichiura among the helminths and E. histolytica/dispar and E. coli among the protozoans were the dominant parasites detected both on the external and in the gut contents of the flies, but occurring more in the latter. Among the flies, C. rufifacies and M. sorbens were the highest carriers of the helminth and protozoan parasites, respectively. The public health significance of these findings is highlighted.

Dog-walking behaviours affect gastrointestinal parasitism in park-attending dogs.

PubMed

Smith, Anya F; Semeniuk, Christina A D; Kutz, Susan J; Massolo, Alessandro

2014-09-04

In urban parks, dogs, wildlife and humans can be sympatric, introducing the potential for inter- and intra-specific transmission of pathogens among hosts. This study was conducted to determine the prevalence of zoonotic and non-zoonotic gastrointestinal parasites in dogs in Calgary city parks, and assess if dog-walking behaviour, park management, history of veterinary care, and dog demographics were associated with parasitism in dogs From June to September 2010, 645 questionnaires were administered to dog owners in nine city parks to determine behavioural and demographic factors, and corresponding feces from 355 dogs were collected. Dog feces were analyzed for helminth and some protozoan species using a modified sugar flotation technique and microscopic examination, a subsample was analyzed for Giardia spp. and Cryptosporidium spp. using a direct immunofluorescence assay. Descriptive and multivariate statistics were conducted to determine associations among behaviours, demographics, and parasite prevalence and infection intensities Parasite prevalence was 50.2%. Giardia spp. (24.7%), Cryptosporidium spp. (14.7%), and Cystoisospora spp. (16.8%) were the most prevalent parasites. Helminth prevalence was low (4.1%). Presence of Giardia spp. was more likely in intact and young dogs; and infection with any parasite and Giardia spp. intensity were both positively associated with dogs visiting multiple parks coupled with a high frequency of park use and off-leash activity, and with being intact and young. Cryptosporidium spp. intensity was associated with being intact and young, and having visited the veterinarian within the previous year Our results indicate a higher overall prevalence of protozoa in dogs than previously found in Calgary. The zoonotic potential of some parasites found in park-attending dogs may be of interest for public health. These results are relevant for informing park managers, the public health sector, and veterinarians.

Developmental changes in the adhesive disk during Giardia differentiation.

PubMed

Palm, Daniel; Weiland, Malin; McArthur, Andrew G; Winiecka-Krusnell, Jadwiga; Cipriano, Michael J; Birkeland, Shanda R; Pacocha, Sarah E; Davids, Barbara; Gillin, Frances; Linder, Ewert; Svärd, Staffan

2005-06-01

Giardia lamblia is a protozoan parasite infecting the upper mammalian small intestine. Infection relies upon the ability of the parasite to attach to the intestine via a unique cytoskeletal organelle, the ventral disk. We determined the composition and structure of the disk throughout the life cycle of the parasite and identified a new disk protein, SALP-1. SALP-1 is an immunodominant protein related to striated fiber-assemblin (SFA). The disk is disassembled during encystation and stored as four fragments in the immobile cyst. Serial Analysis of Gene Expression (SAGE) showed that the mRNA levels of the disk proteins decreased in encystation but two-dimensional protein gels showed that the protein levels were more constant. The parasite emerges without a functional disk but the four disk fragments are quickly reassembled into two new disks on the dividing, early excysting form. Thus, disk proteins are stored within the cyst, ready to be used in the rapid steps of excystation.

Albendazole induces oxidative stress and DNA damage in the parasitic protozoan Giardia duodenalis

PubMed Central

Martínez-Espinosa, Rodrigo; Argüello-García, Raúl; Saavedra, Emma; Ortega-Pierres, Guadalupe

2015-01-01

The control of Giardia duodenalis infections is carried out mainly by drugs, among these albendazole (ABZ) is commonly used. Although the cytotoxic effect of ABZ usually involves binding to β-tubulin, it has been suggested that oxidative stress may also play a role in its parasiticidal mechanism. In this work the effect of ABZ in Giardia clones that are susceptible or resistant to different concentrations (1.35, 8, and 250 μM) of this drug was analyzed. Reactive oxygen species (ROS) were induced by ABZ in susceptible clones and this was associated with a decrease in growth that was alleviated by cysteine supplementation. Remarkably, ABZ-resistant clones exhibited partial cross-resistance to H2O2, whereas a Giardia H2O2-resistant strain can grow in the presence of ABZ. Lipid oxidation and protein carbonylation in ABZ-treated parasites did not show significant differences as compared to untreated parasites; however, ABZ induced the formation of 8OHdG adducts and DNA degradation, indicating nucleic acid oxidative damage. This was supported by observations of histone H2AX phosphorylation in ABZ-susceptible trophozoites treated with 250 μM ABZ. Flow cytometry analysis showed that ABZ partially arrested cell cycle in drug-susceptible clones at G2/M phase at the expense of cells in G1 phase. Also, ABZ treatment resulted in phosphatidylserine exposure on the parasite surface, an event related to apoptosis. All together these data suggest that ROS induced by ABZ affect Giardia genetic material through oxidative stress mechanisms and subsequent induction of apoptotic-like events. PMID:26300866

Recent advances in molecular biology of parasitic viruses.

PubMed

Banik, Gouri Rani; Stark, Damien; Rashid, Harunor; Ellis, John T

2014-01-01

The numerous protozoa that can inhabit the human gastro-intestinal tract are known, yet little is understood of the viruses which infect these protozoa. The discovery, morphologic details, purification methods of virus-like particles, genome and proteome of the parasitic viruses, Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, and the Eimeria sp. are described in this review. The protozoan viruses share many common features: most of them are RNA or double-stranded RNA viruses, ranging between 5 and 8 kilobases, and are spherical or icosahedral in shape with an average diameter of 30-40 nm. These viruses may influence the function and pathogenicity of the protozoa which they infect, and may be important to investigate from a clinical perspective. The viruses may be used as specific genetic transfection vectors for the parasites and may represent a research tool. This review provides an overview on recent advances in the field of protozoan viruses.

Interactions of Cryptosporidium parvum, Giardia lamblia, Vaccinal Poliovirus Type 1, and Bacteriophages φX174 and MS2 with a Drinking Water Biofilm and a Wastewater Biofilm▿

PubMed Central

Helmi, Karim; Skraber, Sylvain; Gantzer, Christophe; Willame, Raphaël; Hoffmann, Lucien; Cauchie, Henry-Michel

2008-01-01

Biofilms colonizing surfaces inside drinking water distribution networks may provide a habitat and shelter to pathogenic viruses and parasites. If released from biofilms, these pathogens may disseminate in the water distribution system and cause waterborne diseases. Our study aimed to investigate the interactions of protozoan parasites (Cryptosporidium parvum and Giardia lamblia [oo]cysts) and viruses (vaccinal poliovirus type 1, φX174, and MS2) with two contrasting biofilms. First, attachment, persistence, and detachment of the protozoan parasites and the viruses were assessed with a drinking water biofilm. This biofilm was allowed to develop inside a rotating annular reactor fed with tap water for 7 months prior to the inoculation. Our results show that viable parasites and infectious viruses attached to the drinking water biofilm within 1 h and persisted within the biofilm. Indeed, infectious viruses were detected in the drinking water biofilm up to 6 days after the inoculation, while viral genome and viable parasites were still detected at day 34, corresponding to the last day of the monitoring period. Since viral genome was detected much longer than infectious particles, our results raise the question of the significance of detecting viral genomes in biofilms. A transfer of viable parasites and viruses from the biofilm to the water phase was observed after the flow velocity was increased but also with a constant laminar flow rate. Similar results regarding parasite and virus attachment and detachment were obtained using a treated wastewater biofilm, suggesting that our observations might be extrapolated to a wide range of environmental biofilms and confirming that biofilms can be considered a potential secondary source of contamination. PMID:18281435

Interactions of Cryptosporidium parvum, Giardia lamblia, vaccinal poliovirus type 1, and bacteriophages phiX174 and MS2 with a drinking water biofilm and a wastewater biofilm.

PubMed

Helmi, Karim; Skraber, Sylvain; Gantzer, Christophe; Willame, Raphaël; Hoffmann, Lucien; Cauchie, Henry-Michel

2008-04-01

Biofilms colonizing surfaces inside drinking water distribution networks may provide a habitat and shelter to pathogenic viruses and parasites. If released from biofilms, these pathogens may disseminate in the water distribution system and cause waterborne diseases. Our study aimed to investigate the interactions of protozoan parasites (Cryptosporidium parvum and Giardia lamblia [oo]cysts) and viruses (vaccinal poliovirus type 1, phiX174, and MS2) with two contrasting biofilms. First, attachment, persistence, and detachment of the protozoan parasites and the viruses were assessed with a drinking water biofilm. This biofilm was allowed to develop inside a rotating annular reactor fed with tap water for 7 months prior to the inoculation. Our results show that viable parasites and infectious viruses attached to the drinking water biofilm within 1 h and persisted within the biofilm. Indeed, infectious viruses were detected in the drinking water biofilm up to 6 days after the inoculation, while viral genome and viable parasites were still detected at day 34, corresponding to the last day of the monitoring period. Since viral genome was detected much longer than infectious particles, our results raise the question of the significance of detecting viral genomes in biofilms. A transfer of viable parasites and viruses from the biofilm to the water phase was observed after the flow velocity was increased but also with a constant laminar flow rate. Similar results regarding parasite and virus attachment and detachment were obtained using a treated wastewater biofilm, suggesting that our observations might be extrapolated to a wide range of environmental biofilms and confirming that biofilms can be considered a potential secondary source of contamination.

Waterborne transmission of protozoan parasites: Review of worldwide outbreaks - An update 2011-2016.

PubMed

Efstratiou, Artemis; Ongerth, Jerry E; Karanis, Panagiotis

2017-05-01

This review provides a comprehensive update of worldwide waterborne parasitic protozoan outbreaks that occurred with reports published since previous reviews largely between January 2011 and December 2016. At least 381 outbreaks attributed to waterborne transmission of parasitic protozoa were documented during this time period. The nearly half (49%) of reports occurred in New Zealand, 41% of the outbreaks in North America and 9% in Europe. The most common etiological agent was Cryptosporidium spp., reported in 63% (239) of the outbreaks, while Giardia spp. was mentioned in 37% (142). No outbreaks attributed to other parasitic protozoa were reported. The distribution of reported outbreaks does not correspond to more broadly available epidemiological data or general knowledge of water and environmental conditions in the reporting countries. Noticeably, developing countries that are probably most affected by such waterborne disease outbreaks still lack reliable surveillance systems, and an international standardization of surveillance and reporting systems has yet to be established. Copyright © 2017 Elsevier Ltd. All rights reserved.

Deconjugated Bile Salts Produced by Extracellular Bile-Salt Hydrolase-Like Activities from the Probiotic Lactobacillus johnsonii La1 Inhibit Giardia duodenalis In vitro Growth.

PubMed

Travers, Marie-Agnès; Sow, Cissé; Zirah, Séverine; Deregnaucourt, Christiane; Chaouch, Soraya; Queiroz, Rayner M L; Charneau, Sébastien; Allain, Thibault; Florent, Isabelle; Grellier, Philippe

2016-01-01

Giardiasis, currently considered a neglected disease, is caused by the intestinal protozoan parasite Giardia duodenalis and is widely spread in human as well as domestic and wild animals. The lack of appropriate medications and the spread of resistant parasite strains urgently call for the development of novel therapeutic strategies. Host microbiota or certain probiotic strains have the capacity to provide some protection against giardiasis. By combining biological and biochemical approaches, we have been able to decipher a molecular mechanism used by the probiotic strain Lactobacillus johnsonii La1 to prevent Giardia growth in vitro . We provide evidence that the supernatant of this strain contains active principle(s) not directly toxic to Giardia but able to convert non-toxic components of bile into components highly toxic to Giardia . By using bile acid profiling, these components were identified as deconjugated bile-salts. A bacterial bile-salt-hydrolase of commercial origin was able to mimic the properties of the supernatant. Mass spectrometric analysis of the bacterial supernatant identified two of the three bile-salt-hydrolases encoded in the genome of this probiotic strain. These observations document a possible mechanism by which L. johnsonii La1, by secreting, or releasing BSH-like activity(ies) in the vicinity of replicating Giardia in an environment where bile is present and abundant, can fight this parasite. This discovery has both fundamental and applied outcomes to fight giardiasis, based on local delivery of deconjugated bile salts, enzyme deconjugation of bile components, or natural or recombinant probiotic strains that secrete or release such deconjugating activities in a compartment where both bile salts and Giardia are present.

Deconjugated Bile Salts Produced by Extracellular Bile-Salt Hydrolase-Like Activities from the Probiotic Lactobacillus johnsonii La1 Inhibit Giardia duodenalis In vitro Growth

PubMed Central

Travers, Marie-Agnès; Sow, Cissé; Zirah, Séverine; Deregnaucourt, Christiane; Chaouch, Soraya; Queiroz, Rayner M. L.; Charneau, Sébastien; Allain, Thibault; Florent, Isabelle; Grellier, Philippe

2016-01-01

Giardiasis, currently considered a neglected disease, is caused by the intestinal protozoan parasite Giardia duodenalis and is widely spread in human as well as domestic and wild animals. The lack of appropriate medications and the spread of resistant parasite strains urgently call for the development of novel therapeutic strategies. Host microbiota or certain probiotic strains have the capacity to provide some protection against giardiasis. By combining biological and biochemical approaches, we have been able to decipher a molecular mechanism used by the probiotic strain Lactobacillus johnsonii La1 to prevent Giardia growth in vitro. We provide evidence that the supernatant of this strain contains active principle(s) not directly toxic to Giardia but able to convert non-toxic components of bile into components highly toxic to Giardia. By using bile acid profiling, these components were identified as deconjugated bile-salts. A bacterial bile-salt-hydrolase of commercial origin was able to mimic the properties of the supernatant. Mass spectrometric analysis of the bacterial supernatant identified two of the three bile-salt-hydrolases encoded in the genome of this probiotic strain. These observations document a possible mechanism by which L. johnsonii La1, by secreting, or releasing BSH-like activity(ies) in the vicinity of replicating Giardia in an environment where bile is present and abundant, can fight this parasite. This discovery has both fundamental and applied outcomes to fight giardiasis, based on local delivery of deconjugated bile salts, enzyme deconjugation of bile components, or natural or recombinant probiotic strains that secrete or release such deconjugating activities in a compartment where both bile salts and Giardia are present. PMID:27729900

Quantitative proteomics in Giardia duodenalis-Achievements and challenges.

PubMed

Emery, Samantha J; Lacey, Ernest; Haynes, Paul A

2016-08-01

Giardia duodenalis (syn. G. lamblia and G. intestinalis) is a protozoan parasite of vertebrates and a major contributor to the global burden of diarrheal diseases and gastroenteritis. The publication of multiple genome sequences in the G. duodenalis species complex has provided important insights into parasite biology, and made post-genomic technologies, including proteomics, significantly more accessible. The aims of proteomics are to identify and quantify proteins present in a cell, and assign functions to them within the context of dynamic biological systems. In Giardia, proteomics in the post-genomic era has transitioned from reliance on gel-based systems to utilisation of a diverse array of techniques based on bottom-up LC-MS/MS technologies. Together, these have generated crucial foundations for subcellular proteomes, elucidated intra- and inter-assemblage isolate variation, and identified pathways and markers in differentiation, host-parasite interactions and drug resistance. However, in Giardia, proteomics remains an emerging field, with considerable shortcomings evident from the published research. These include a bias towards assemblage A, a lack of emphasis on quantitative analytical techniques, and limited information on post-translational protein modifications. Additionally, there are multiple areas of research for which proteomic data is not available to add value to published transcriptomic data. The challenge of amalgamating data in the systems biology paradigm necessitates the further generation of large, high-quality quantitative datasets to accurately model parasite biology. This review surveys the current proteomic research available for Giardia and evaluates their technical and quantitative approaches, while contextualising their biological insights into parasite pathology, isolate variation and eukaryotic evolution. Finally, we propose areas of priority for the generation of future proteomic data to explore fundamental questions in Giardia, including the analysis of post-translational modifications, and the design of MS-based assays for validation of differentially expressed proteins in large datasets. Copyright © 2016 Elsevier B.V. All rights reserved.

Prevalence of pathogenic free-living amoeba and other protozoa in natural and communal piped tap water from Queen Elizabeth protected area, Uganda.

PubMed

Sente, Celsus; Erume, Joseph; Naigaga, Irene; Mulindwa, Julius; Ochwo, Sylvester; Magambo, Phillip Kimuda; Namara, Benigna Gabriela; Kato, Charles Drago; Sebyatika, George; Muwonge, Kevin; Ocaido, Michael

2016-08-03

Pathogenic water dwelling protozoa such as Acanthamoeba spp., Hartmannella spp., Naegleria spp., Cryptosporidium spp. and Giardia spp. are often responsible for devastating illnesses especially in children and immunocompromised individuals, yet their presence and prevalence in certain environment in sub-Saharan Africa is still unknown to most researchers, public health officials and medical practitioners. The objective of this study was to establish the presence and prevalence of pathogenic free-living amoeba (FLA), Cryptosporidium and Giardia in Queen Elizabeth Protected Area (QEPA). Samples were collected from communal taps and natural water sites in QEPA. Physical water parameters were measured in situ. The samples were processed to detect the presence of FLA trophozoites by xenic cultivation, Cryptosporidium oocysts by Ziehl-Neelsen stain and Giardia cysts by Zinc Sulphate floatation technique. Parasites were observed microscopically, identified, counted and recorded. For FLA, genomic DNA was extracted for amplification and sequencing. Both natural and tap water sources were contaminated with FLA, Cryptosporidium spp. and Giardia spp. All protozoan parasites were more abundant in the colder rainy season except for Harmannella spp. and Naegleria spp. which occurred more in the warmer months. The prevalence of all parasites was higher in tap water than in natural water samples. There was a strong negative correlation between the presence of Acanthamoeba spp., Hartmannella spp., Cryptosporidium spp. and Giardia spp. with Dissolved Oxygen (DO) (P < 0.05). The presence of Cryptosporidium spp. showed a significant positive correlation (P < 0.05) with conductivity, pH and Total Dissolved Solids (TDS); whereas the presence of Giardia spp. had only a strong positive correlation with TDS. Molecular genotyping of FLA produced 7 Acanthamoeba, 5 Echinamoeba, 2 Hartmannella, 1 Bodomorpha, 1 Nuclearia and 1 Cercomonas partial sequences. All water collection sites were found to be contaminated with pathogenic protozoa that could possibly be the cause of a number of silent morbidities and mortalities among rural households in QEPA. This implies that water used by communities in QEPA is of poor quality and predisposes them to a variety of protozoan infections including the FLA whose public health importance was never reported, thus necessitating adoption of proper water safety measures.

Ethanol and Isopropanol in Concentrations Present in Hand Sanitizers Sharply Reduce Excystation of Giardia and Entamoeba and Eliminate Oral Infectivity of Giardia Cysts in Gerbils

PubMed Central

Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin

2015-01-01

Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba. PMID:26282413

Giardia's Epithelial Cell Interaction In Vitro: Mimicking Asymptomatic Infection?

PubMed Central

Kraft, Martin R.; Klotz, Christian; Bücker, Roland; Schulzke, Jörg-Dieter; Aebischer, Toni

2017-01-01

The protozoan parasite Giardia duodenalis is responsible for more than 280 million cases of gastrointestinal complaints (“giardiasis”) every year, worldwide. Infections are acquired orally, mostly via uptake of cysts in contaminated drinking water. After transformation into the trophozoite stage, parasites start to colonize the duodenum and upper jejunum where they attach to the intestinal epithelium and replicate vegetatively. Outcome of Giardia infections vary between individuals, from self-limiting to chronic, and asymptomatic to severely symptomatic infection, with unspecific gastrointestinal complaints. One proposed mechanism for pathogenesis is the breakdown of intestinal barrier function. This has been studied by analyzing trans-epithelial electric resistances (TEER) or by indicators of epithelial permeability using labeled sugar compounds in in vitro cell culture systems, mouse models or human biopsies and epidemiological studies. Here, we discuss the results obtained mainly with epithelial cell models to highlight contradictory findings. We relate published studies to our own findings that suggest a lack of barrier compromising activities of recent G. duodenalis isolates of assemblage A, B, and E in a Caco-2 model system. We propose that this epithelial cell model be viewed as mimicking asymptomatic infection. This view will likely lead to a more informative use of the model if emphasis is shifted from aiming to identify Giardia virulence factors to defining non-parasite factors that arguably appear to be more decisive for disease. PMID:29018775

Immune Response to Giardia duodenalis

PubMed Central

Faubert, Gaétan

2000-01-01

The intestinal protozoan Giardia duodenalis is a widespread opportunistic parasite of humans and animals. This parasite inhabits the upper part of the small intestine and has a direct life cycle. After ingestion of cysts, which are the infective stage, the trophozoites emerge from the cysts in the duodenum and attach to the small intestinal mucosa of the host. Since the migration of trophozoites from the lumen of the intestine into surrounding tissues is an unusual occurrence, the immune response to Giardia remains localized. The identification of antigens that play a role in acquired immunity has been difficult because of the occurrence of antigenic variation and because, Giardia being an ubiquituous organism, it is possible that the antigenic profiles of isolates from different geographic areas will vary. Innate-immunity mechanisms play a role in the control and/or severity of the infection. Both humoral and cell-mediated immune responses play a role in acquired immunity, but the mechanisms involved are unknown. A variety of serological assays have been used to detect circulating antibodies in serum. Because of the biological characteristics of the parasite and the lack of suitable antigens, the sensitivity of serological assays remains poor. On the other hand, detection of antigens in feces of infected patients has met with success. Commercial kits are available, and they are reported to be more sensitive than microscopic examination for the detection of giardiasis on a single specimen. PMID:10627490

Giardia duodenalis Infections in Humans and Other Animals in China

PubMed Central

Li, Junqiang; Wang, Haiyan; Wang, Rongjun; Zhang, Longxian

2017-01-01

Giardia duodenalis is an important zoonotic pathogen in both public and veterinary health, and has been genotyped into at least eight assemblages (A–H), each with a distinct host range. In recent years, this intestinal protozoan parasite has been identified widely in humans and various other animals, and has even been recorded in environmental contaminants. Along with whole genome sequencing of G. duodenalis, multilocus sequence typing is increasingly being used to characterize G. duodenalis isolates. Here, we review the epidemiology, genotyping, and subtyping of G. duodenalis from humans and a wide range of other animals, as well as from wastewater, in China. PMID:29081771

Axenic isolation of viable Giardia muris trophozoites.

PubMed

Tillotson, K D; Buret, A; Olson, M E

1991-06-01

Large numbers of viable Giardia muris trophozoites were isolated from the duodenum of experimentally infected mice 6 days after inoculation with 1,000 G. muris cysts. A series of shaking, incubation, and washing steps in the presence of the broad-spectrum antibiotic piperacillin readily provided 4.9 +/- 1.5 x 10(5) G. muris trophozoites per mouse, free of detectable contaminant organisms. Anaerobic and microaerophilic culturing and scanning electron microscopy demonstrated axenic status and high purity of the isolates. The viability of trophozoites was 98 +/- 2%. Application of this technique should permit novel immunological and epidemiological analyses of G. muris infection and biochemical investigations of this protozoan parasite.

Factors influencing growth and intestinal parasitic infections in preschoolers attending philanthropic daycare centers in Salvador, Northeast Region of Brazil.

PubMed

Lander, Rebecca L; Lander, Alastair G; Houghton, Lisa; Williams, Sheila M; Costa-Ribeiro, Hugo; Barreto, Daniel L; Mattos, Angela P; Gibson, Rosalind S

2012-11-01

Poor growth and intestinal parasitic infections are widespread in disadvantaged urban children. This cross-sectional study assessed factors influencing poor growth and intestinal parasites in 376 children aged three to six years in daycare centers in Salvador, in the Northeast Region of Brazil. Data was obtained from seven daycare centers on child weight, height, socio-economic status, health and intestinal parasites in stool samples. Prevalence of moderate underweight (< -1SD > -2SD), wasting and stunting was 12%, 16% and 6% respectively. Socioeconomic status, birth order, and maternal weight were predictors of poor anthropometric status. Almost 30% of children were infected with more than one intestinal parasite. Helminths (17.8%), notably Trichuris trichiura (12%) and Ascaris lumbricoides (10.5%), and protozoan Giardia duodenalis (13%) were the most common types of parasites detected. One percent of children had hookworm and Cryptosporidium sp. and 25% had non-pathogenic protozoan cysts. Boys from families with very low socio-economic status had lower linear growth and presented a greater risk of helminth infection. Deworming is considered an alternative for reducing the prevalence of intestinal parasitic infections in this age group.

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.

Prevalence and Risk Factors of Human Intestinal Parasites in Roudehen, Tehran Province, Iran.

PubMed

Hemmati, Nasrin; Razmjou, Elham; Hashemi-Hafshejani, Saeideh; Motevalian, Abbas; Akhlaghi, Lameh; Meamar, Ahmad Reza

2017-01-01

Intestinal parasitic infections are among the most common infections and health problems worldwide. Due to the lack of epidemiologic information of such infections, the prevalence of, and the risk factors for, enteric parasites were investigated in residents of Roudehen, Tehran Province, Iran. In this cross-sectional study, 561 triple fecal samples were collected through a two-stage cluster-sampling protocol from Jun to Dec 2014. The samples were examined by formalin-ether concentration, culture, and with molecular methods. The prevalence of enteric parasites was 32.7% (95% CI 27.3-38). Blastocystis sp. was the most common intestinal protozoan (28.4%; 95% CI 23.7-33.0). The formalin-ether concentration and culture methods detected Blastocystis sp., Entamoeba coli , Giardia intestinalis , Dientamoeba fragilis , Iodamoeba butschlii , Entamoeba complex cysts or trophozoite , Chilomastix mesnilii , and Enterobius vermicularis . Single-round PCR assay for Entamoeba complex were identified Entamoeba dispar and E. moshkovskii . E. histolytica was not observed in any specimen. Multivariate analysis showed a significant association of parasites with water source and close animal contact. There was no correlation between infections and gender, age, occupation, education, or travel history. Protozoan infections were more common than helminth infections. This study revealed a high prevalence of enteric protozoan parasite infection among citizens of Rodehen. As most of the species detected are transmitted through a water-resistant cyst, public and individual education on personal hygiene should be considered to reduce transmission of intestinal parasites in the population.

Detection and molecular characterization of Giardia and Cryptosporidium in common dolphins (Delphinus delphis) stranded along the Galician coast (Northwest Spain).

PubMed

Reboredo-Fernández, A; Gómez-Couso, H; Martínez-Cedeira, J A; Cacciò, S M; Ares-Mazás, E

2014-05-28

The ubiquitous protozoan parasites Giardia and Cryptosporidium have been detected from many species of captive and free-living wildlife, representing most mammalian orders. Twenty species of marine mammals have been reported to inhabit Galician waters and the region has one of the highest rates of stranding in Europe. Evidence from stranding, reported by-catches and sightings, suggests that the common dolphin (Delphinus delphis) is the most abundant cetacean on the Galician coast (Northwest Spain). The objective of this study was to detect and molecularly characterize isolates of Giardia and Cryptosporidium obtained from common dolphins stranded in this area. Between 2005 and 2012, sections of large intestine from 133 common dolphins stranded along the Galician coast were collected by the personnel of the Galician Stranding Network (Coordinadora para o Estudo dos Mamíferos Mariños, CEMMA). Using direct immunofluorescence antibody test (IFAT) and PCR amplification and sequencing of the SSU-rDNA, β-giardin genes and the ITS1-5.8S-ITS2 region, Giardia and Cryptosporidium were detected in 8 (6.0%) and 12 samples (9.0%), respectively. In two samples, co-infection by both parasites was observed. The molecular characterization revealed the presence of Giardia duodenalis assemblages A (genotypes A1 and A2) and B and Cryptosporidium parvum in these samples. This constitutes the first study in which the presence of Giardia and Cryptosporidium has been investigated in common dolphins on the European Atlantic coast, and it is also the first report of C. parvum in this host. Our findings indicate that these animals could act as reservoir of these waterborne parasites or could be victims of the contamination originated by anthropogenic activities. Copyright © 2014 Elsevier B.V. All rights reserved.

A decade of intestinal protozoan epidemiology among settled immigrants in Qatar.

PubMed

Abu-Madi, Marawan A; Behnke, Jerzy M; Boughattas, Sonia; Al-Thani, Asma; Doiphode, Sanjay H

2016-08-05

The World Health Organization estimates that about 3.5 billion people worldwide are affected by intestinal parasitic infections. Reports have already emphasized the role of immigrants in outbreaks of parasitic diseases in industrialized countries. With the mass influx of immigrants to Qatar, patent intestinal parasitic infections have been observed. Herein, the prevalence of intestinal protozoan infections was analysed in 29,286 records of subjects referred for stool examination at the Hamad Medical Corporation over the course of a decade (2005 to 2014, inclusive). Overall prevalence of combined protozoan infections was 5.93 % but there were significant temporal trends, age and sex effects and those arising from the region of origin of the subjects. The most common protozoan was Blastocystis hominis (overall prevalence 3.45 %). Giardia duodenalis, Chilomastix mesnili, Entamoeba coli, Entamoeba hartmanni, Endolimax nana, Iodamoeba butschlii, Entamoeba histolytica/dispar, Cryptosporidium sp. and a single case of Isospora were also detected. The prevalence of combined protozoan infections, G. duodenalis and the non-pathogenic amoebae all declined significantly across the decade. That of B. hominis varied between years but showed no directional trend across years and there was no evidence that prevalence of E. histolyitica/dispar changed significantly. Protozoan infections were observed among all regional groups, but prevalence was higher among subjects from the Arabian Peninsula, Africa and Asia compared to those from the Eastern Mediterranean and Qatar. Prevalence was higher among male subjects in all cases, but age-prevalence profiles differed between the taxa. These results offer optimism that prevalence will continue to decline in the years ahead.

Endoparasite survey of free-swimming baleen whales (Balaenoptera musculus, B. physalus, B. borealis) and sperm whales (Physeter macrocephalus) using non/minimally invasive methods.

PubMed

Hermosilla, Carlos; Silva, Liliana M R; Kleinertz, Sonja; Prieto, Rui; Silva, Monica A; Taubert, Anja

2016-02-01

A number of parasitic diseases have gained importance as neozoan opportunistic infections in the marine environment. Here, we report on the gastrointestinal endoparasite fauna of three baleen whale species and one toothed whale: blue (Balaenoptera musculus), fin (Balaenoptera physalus), and sei whales (Balaenoptera borealis) and sperm whales (Physeter macrocephalus) from the Azores Islands, Portugal. In total, 17 individual whale fecal samples [n = 10 (B. physalus); n = 4 (P. macrocephalus); n = 2 (B. musculus); n = 1 (B. borealis)] were collected from free-swimming animals as part of ongoing studies on behavioral ecology. Furthermore, skin biopsies were collected from sperm whales (n = 5) using minimally invasive biopsy darting and tested for the presence of Toxoplasma gondii, Neospora caninum, and Besnoitia besnoiti DNA via PCR. Overall, more than ten taxa were detected in whale fecal samples. Within protozoan parasites, Entamoeba spp. occurred most frequently (64.7%), followed by Giardia spp. (17.6%) and Balantidium spp. (5.9%). The most prevalent metazoan parasites were Ascaridida indet. spp. (41.2%), followed by trematodes (17.7%), acanthocephalan spp., strongyles (11.8%), Diphyllobotrium spp. (5.9%), and spirurids (5.9%). Helminths were mainly found in sperm whales, while enteric protozoan parasites were exclusively detected in baleen whales, which might be related to dietary differences. No T. gondii, N. caninum, or B. besnoiti DNA was detected in any skin sample. This is the first record on Giardia and Balantidium infections in large baleen whales.

Expression, purification, crystallization and preliminary X-ray diffraction analysis of α-11 giardin from Giardia lamblia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pathuri, Puja; Nguyen, Emily Tam; Luecke, Hartmut, E-mail: hudel@uci.edu

2006-11-01

α-11 giardin from the intestinal protozoan parasite, G. lamblia has been cloned, expressed, purified and crystallized under two different conditions and in two different space groups. Crystals from the first condition diffracted to 1.1 Å and belong to a primitive orthorhombic space group and crystals obtained in the second condition diffracted to 2.93 Å and belong to a primitive monoclinic space group. α-11 Giardin, a protein from the annexin superfamily, is a 35.0 kDa protein from the intestinal protozoan parasite Giardia lamblia which triggers a form of diarrhea called giardiasis. Here, the cloning, expression, purification and the crystallization of α-11more » giardin under two different conditions and in two different space groups is reported. Crystals from the first condition diffracted to 1.1 Å and belong to a primitive orthorhombic space group, while crystals from the second condition, which included calcium in the crystallization solution, diffracted to 2.93 Å and belong to a primitive monoclinic space group. Determination of the detailed atomic structure of α-11 giardin will provide a better insight into its biological function and might establish whether this class of proteins is a potential drug target against giardiasis.« less

Detection and genotyping of Entamoeba histolytica, Entamoeba dispar, Giardia lamblia, and Cryptosporidium parvum by oligonucleotide microarray.

PubMed

Wang, Zheng; Vora, Gary J; Stenger, David A

2004-07-01

Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum are the most frequently identified protozoan parasites causing waterborne disease outbreaks. The morbidity and mortality associated with these intestinal parasitic infections warrant the development of rapid and accurate detection and genotyping methods to aid public health efforts aimed at preventing and controlling outbreaks. In this study, we describe the development of an oligonucleotide microarray capable of detecting and discriminating between E. histolytica, Entamoeba dispar, G. lamblia assemblages A and B, and C. parvum types 1 and 2 in a single assay. Unique hybridization patterns for each selected protozoan were generated by amplifying six to eight diagnostic sequences/organism by multiplex PCR; fluorescent labeling of the amplicons via primer extension; and subsequent hybridization to a set of genus-, species-, and subtype-specific covalently immobilized oligonucleotide probes. The profile-based specificity of this methodology not only permitted for the unequivocal identification of the six targeted species and subtypes, but also demonstrated its potential in identifying related species such as Cryptosporidium meleagridis and Cryptosporidium muris. In addition, sensitivity assays demonstrated lower detection limits of five trophozoites of G. lamblia. Taken together, the specificity and sensitivity of the microarray-based approach suggest that this methodology may provide a promising tool to detect and genotype protozoa from clinical and environmental samples.

Ethanol and isopropanol in concentrations present in hand sanitizers sharply reduce excystation of Giardia and Entamoeba and eliminate oral infectivity of Giardia cysts in gerbils.

PubMed

Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin; Samuelson, John

2015-11-01

Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Mining the Giardia genome and proteome for conserved and unique basal body proteins

PubMed Central

Lauwaet, Tineke; Smith, Alias J.; Reiner, David S.; Romijn, Edwin P.; Wong, Catherine C. L.; Davids, Barbara J.; Shah, Sheila A.; Yates, John R.; Gillin, Frances D.

2015-01-01

Giardia lamblia is a flagellated protozoan parasite and a major cause of diarrhea in humans. Its microtubular cytoskeleton mediates trophozoite motility, attachment and cytokinesis, and is characterized by an attachment disk and eight flagella that are each nucleated in a basal body. To date, only 10 giardial basal body proteins have been identified, including universal signaling proteins that are important for regulating mitosis or differentiation. In this study, we have exploited bioinformatics and proteomic approaches to identify new Giardia basal body proteins and confocal microscopy to confirm their localization in interphase trophozoites. This approach identified 75 homologs of conserved basal body proteins in the genome including 65 not previously known to be associated with Giardia basal bodies. Thirteen proteins were confirmed to co-localize with centrin to the Giardia basal bodies. We also demonstrate that most basal body proteins localize to additional cytoskeletal structures in interphase trophozoites. This might help to explain the roles of the four pairs of flagella and Giardia-specific organelles in motility and differentiation. A deeper understanding of the composition of the Giardia basal bodies will contribute insights into the complex signaling pathways that regulate its unique cytoskeleton and the biological divergence of these conserved organelles. PMID:21723868

Prevalence of Giardia in dairy cattle in Lusaka and Chilanga districts, Zambia.

PubMed

Kakandelwa, Cliff; Siwila, Joyce; Nalubamba, King S; Muma, John B; Phiri, Isaac G K

2016-01-15

Giardia is an intestinal protozoan parasite of mammals including humans. A cross-sectional study was conducted to estimate prevalence of Giardia infections in smallholder and commercial dairy herds in Chilanga and Lusaka districts of Zambia. A total of 377 calves aged from 1 to 365 days were sampled on 34 farms. All faecal samples were analyzed for Giardia antigen using a commercially available ELISA kit. Overall prevalence of Giardia was 34.5% (95% CI=29.7-39.3). Among smallholder farms, animal level prevalence ranged from 0 to 100% (mean=44.6±36.9 standard deviations) and 12.5 to 60.9% (mean=33.5±16.7 standard deviations) within commercial herds. Prevalence was highest in calves less than three months old (p=0.010), and there was no significant difference in the prevalence between smallholder and commercial farms (p=0.300). Giardia prevalence was not associated with occurrence of diarrhoea in the calves (p=0.205). The study demonstrates that Giardia infections are common in dairy herds in the study areas, especially in calves less than three months of age. Copyright © 2015 Elsevier B.V. All rights reserved.

A new-generation 5-nitroimidazole can induce highly metronidazole-resistant Giardia lamblia in vitro

PubMed Central

Dunn, Linda A.; Burgess, Anita G.; Krauer, Kenia G.; Eckmann, Lars; Vanelle, Patrice; Crozet, Maxime D.; Gillin, Frances D.; Upcroft, Peter; Upcroft, Jacqueline A.

2010-01-01

The 5-nitroimidazole (NI) compound C17, with a side chain carrying a remote phenyl group in the 2-position of the imidazole ring, is at least 14-fold more active against the gut protozoan parasite Giardia lamblia than the 5-NI drug metronidazole (MTR), with a side chain in the 1-position of the imidazole ring, which is the primary drug for the treatment of giardiasis. Over 10 months, lines resistant to C17 were induced in vitro and were at least 12-fold more resistant to C17 than the parent strains. However, these lines had ID90 values (concentration of drug at which 10% of control parasite ATP levels are detected) for MTR of >200 μM, whilst lines induced to be highly resistant to MTR in vitro have maximum ID90 values around 100 μM (MTR-susceptible isolates typically have an ID90 of 5–12.8 μM). The mechanism of MTR activation in Giardia apparently involves reduction to toxic radicals by the activity of pyruvate:ferredoxin oxidoreductase (PFOR) and the electron acceptor ferredoxin. MTR-resistant Giardia have decreased PFOR activity, which is consistent with decreased activation of MTR in these lines, but C17-resistant lines have normal levels of PFOR. Therefore, an alternative mechanism of resistance in Giardia must account for these super-MTR-resistant cells. PMID:20456926

Antibody response to Giardia muris trophozoites in mouse intestine.

PubMed

Heyworth, M F

1986-05-01

The protozoan parasite Giardia muris colonizes the mouse small intestinal lumen. This parasite is cleared immunologically from the intestine of normal mice. In contrast, T-lymphocyte-deficient (nude) mice have an impaired immunological response to G. muris and become chronically infected. In the present study, trophozoites were harvested from the intestinal lumen of immunocompetent BALB/c mice and nude mice and examined for surface-bound mouse immunoglobulins by immunofluorescence microscopy. Immunoglobulin A (IgA) and IgG, but not IgM, were detected on trophozoites obtained from BALB/c mice, from day 10 of the infection onwards. Trophozoites from nude mice showed very little evidence of surface-bound mouse immunoglobulin at any time during the 5-week period immediately following infection of these animals with G. muris cysts. Intestinal G. muris infection was cleared by the BALB/c mice but not by the nude animals. The data suggest that parasite-specific IgA and IgG bind to G. muris trophozoites in the intestinal lumen of immunocompetent BALB/c mice. Intestinal antibodies that bind to trophozoite surfaces are likely to play an important part in the clearance of G. muris infection by immunocompetent mice. The inability of nude mice to clear this infection at a normal rate is likely to be due to impairment of Giardia-specific intestinal antibody production.

Prevalence and risk factors of intestinal protozoan infections: a population-based study in rural areas of Boyer-Ahmad district, Southwestern Iran.

PubMed

Sarkari, Bahador; Hosseini, Ghasem; Motazedian, Mohammad Hossein; Fararouei, Mohammad; Moshfe, Abdolali

2016-11-25

Parasitic infections are still a significant health problem in rural areas in developing countries including Iran. There is no recent population-based data about the prevalence of human intestinal parasites in most rural areas of Iran. The current study aimed to determine the prevalence of intestinal protozoan infection in inhabitants of rural areas of Boyer-Ahmad district, Southwestern Iran. A total of 1025 stool samples were collected from the inhabitant of 50 randomly selected villages in Boyer-Ahmad Township. The stool samples were evaluated by parasitological methods including, direct wet-mounting, formalin ethyl acetate concentration, zinc sulfate floatation, and Trichrome permanent stain for detection of protozoan infections. Diarrheic samples were further evaluated with a modified Ziehl-Neelsen staining method for detection of coccidian parasites. The prevalence of both pathogenic and nonpathogenic intestinal parasites in the population was 37.5% (385 out of 1025 cases), some individual with multiple infections. Giardia lamblia was detected in 179 (17.46%), Blastocystis hominis in 182 (17.76%), Entamoeba histolytica/dispar in 9 (0.87%), Endolimax nana in 216 (21.07%), Entamoeba coli in 151 (14.73%), Ioedamoeba butschlii in 45 (4.39%), Chillomastix mesnili in 22 (2.14%), Trichomonas hominis in 2 (0.19%) and Dientamoeba fragillis in 2 (0.19%) of cases. Multivariate logistic regression revealed significant associations between protozoan infection (pathogenic protozoa) and contact with animals (OR yes/no = 2.22, p < 0.001) and educational status (OR higher/illiterate = 0.40, P = 0.01). Findings of this study demonstrated that protozoan infection rate in rural areas of southwestern Iran is still high and remained as a challenging health problem in these areas.

Flavohemoglobin and nitric oxide detoxification in the human protozoan parasite Giardia intestinalis.

PubMed

Mastronicola, Daniela; Testa, Fabrizio; Forte, Elena; Bordi, Eugenio; Pucillo, Leopoldo Paolo; Sarti, Paolo; Giuffrè, Alessandro

2010-09-03

Flavohemoglobins (flavoHbs), commonly found in bacteria and fungi, afford protection from nitrosative stress by degrading nitric oxide (NO) to nitrate. Giardia intestinalis, a microaerophilic parasite causing one of the most common intestinal human infectious diseases worldwide, is the only pathogenic protozoon as yet identified coding for a flavoHb. By NO amperometry we show that, in the presence of NADH, the recombinant Giardia flavoHb metabolizes NO with high efficacy under aerobic conditions (TN=116+/-10s(-1) at 1microM NO, T=37 degrees C). The activity is [O(2)]-dependent and characterized by an apparent K(M,O2)=22+/-7microM. Immunoblotting analysis shows that the protein is expressed at low levels in the vegetative trophozoites of Giardia; accordingly, these cells aerobically metabolize NO with low efficacy. Interestingly, in response to nitrosative stress (24-h incubation with 5mM nitrite) flavoHb expression is enhanced and the trophozoites thereby become able to metabolize NO efficiently, the activity being sensitive to both cyanide and carbon monoxide. The NO-donors S-nitrosoglutathione (GSNO) and DETA-NONOate mimicked the effect of nitrite on flavoHb expression. We propose that physiologically flavoHb contributes to NO detoxification in G. intestinalis. Copyright 2010 Elsevier Inc. All rights reserved.

Identification of Giardia duodenalis and Enterocytozoon bieneusi in an epizoological investigation of a laboratory colony of prairie dogs, Cynomys ludovicianus

PubMed Central

Roellig, Dawn M.; Salzer, Johanna S.; Carroll, Darin S.; Ritter, Jana M.; Drew, Clifton; Gallardo-Romero, Nadia; Keckler, M. Shannon; Langham, Gregory; Hutson, Christina L.; Karem, Kevin L.; Gillespie, Thomas R.; Visvesvara, Govinda S.; Metcalfe, Maureen G.; Damon, Inger K.; Xiao, Lihua

2015-01-01

Since 2005, black-tailed prairie dogs (Cynomys ludovicianus) have been collected for use as research animals from field sites in Kansas, Colorado, and Texas. In January of 2012, Giardia trophozoites were identified by histology, thin-section electron microscopy, and immunofluorescent staining in the lumen of the small intestine and colon of a prairie dog euthanized because of extreme weight loss. With giardiasis suspected as the cause of weight loss, a survey of Giardia duodenalis in the laboratory colony of prairie dogs was initiated. Direct immunofluorescent testing of feces revealed active shedding of Giardia cysts in 40% (n = 60) of animals held in the vivarium. All tested fecal samples (n = 29) from animals in another holding facility where the index case originated were PCR positive for G. duodenalis with assemblages A and B identified from sequencing triosephosphate isomerase (tpi), glutamate dehydrogenase (gdh), and β-giardin (bg) genes. Both assemblages are considered zoonotic, thus the parasites in prairie dogs are potential human pathogens and indicate prairie dogs as a possible wildlife reservoir or the victims of pathogen spill-over. Molecular testing for other protozoan gastrointestinal parasites revealed no Cryptosporidium infections but identified a host-adapted Enterocytozoon bieneusi genotype group. PMID:25881801

Flagellar generated flow mediates attachment of Giardia lamblia

NASA Astrophysics Data System (ADS)

Urbach, Jeffrey; Luo, Haibei; Picou, Theodore; McAllister, Ryan; Elmendorf, Heidi

2011-03-01

Giardia lamblia is a protozoan parasite responsible for widespread diarrheal disease in humans and animals worldwide. Attachment to the host intestinal mucosa and resistance to peristalsis is necessary for establishing infection, but the physical basis for this attachment is poorly understood. We report results from TIRF and confocal fluorescence microscopy that demonstrate that the regular beating of the posterior flagella generate a flow through the ventral disk, a suction-cup shaped structure that is against the substrate during attachment. Finite element simulations are used to compare the negative pressure generated by the flow to the measured attachment force and the expected performance of the flagellar pump. NIH grant 1R21AI062934-0.

Opportunistic parasites among immunosuppressed children in Minia District, Egypt.

PubMed

Abdel-Hafeez, Ekhlas H; Ahmad, Azza K; Ali, Basma A; Moslam, Fadia A

2012-03-01

A total of 450 stool samples were collected from inpatient and outpatient clinics of Pediatric Department, Minia University Hospital, Minia District, Egypt. Two groups of patients were studied, including 200 immunosuppressed and 250 immunocompetent children. Stool samples were subjected to wet saline and iodine mounts. A concentration technique (formol-ether sedimentation method) was carried out for stool samples diagnosed negative by wet saline and iodine mounts. Samples were stained by 2 different methods; acid fast stain (modified Ziehl-Neelsen stain) and Giemsa stain. Total 188 cases (94%) were diagnosed positive for parasitic infections among immunosuppressed children, whereas 150 cases (60%) were positive in immunocompetent children (P<0.0001). The most common protozoan infection in immunosuppressed group was Cryptosporidium parvum (60.2%), followed by Blastocystis hominis (12.1%), Isospora belli (9.7%), and Cyclospora caytenensis (7.8%). On the other hand, Entamoeba histolytica (24.6%) and Giardia lamblia (17.6%) were more common than other protozoans in immunocompetent children.

Keeping it cool: Survival of Giardia cysts and Cryptosporidium oocysts on lettuce leaves.

PubMed

Utaaker, Kjersti Selstad; Skjerve, Eystein; Robertson, Lucy J

2017-08-16

Fresh produce has been recognized as a vehicle for transmission of protozoan parasites for many years, and there are numerous publications regarding their occurrence on such foodstuffs, indicating their potential importance as foodborne parasites. Nevertheless, few studies have been published regarding the effectiveness of this transmission route, and whether contamination is likely to result in transmission. The purpose of this study was to assess the viability of Cryptosporidium oocysts and Giardia cysts, two protozoa associated with both waterborne and foodborne transmission, by spiking fresh produce (lettuce leaves) with viable transmission stages and determining changes in viability. These investigations were performed under different conditions and over time spans that may be used in a regular household; a fridge at 4°C, under ambient temperatures exposed to natural cycles of light during night and day, and inside a cupboard to ensure no light exposure, for a duration of up to two weeks, or as long as the produce remained visually palatable. The major finding from this study is that whereas both Cryptosporidium oocysts and Giardia cysts survive well when kept moist and refrigerated, survival of Giardia cysts was abrogated on lettuce at room temperature. Indeed, almost 50% die-off of Giardia cysts was recorded within the first 24h. Cryptosporidium oocysts had a stable viability throughout the experiment under all the conditions investigated, indicating that fresh produce is a suitable transmission vehicle for Cryptosporidium, even if contamination occurs on-farm and the parasites are exposed to non-favourable storage conditions, as may be common in developing countries. Giardia cysts were not as robust as Cryptosporidium oocysts, and would be probably unlikely to survive under ambient storage conditions on-farm, during sale, or at home. However, if kept refrigerated, then some contaminating Giardia cysts may remain viable and therefore may pose a threat to the consumer. Thus, as the cold chain for transport and storage of fresh produce improves, it is important that similar improvements are implemented to reduce the contamination of fresh produce with parasite transmission stages. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of RNase MRP RNA and novel snoRNAs from Giardia intestinalis and Trichomonas vaginalis

PubMed Central

2011-01-01

Background Eukaryotic cells possess a complex network of RNA machineries which function in RNA-processing and cellular regulation which includes transcription, translation, silencing, editing and epigenetic control. Studies of model organisms have shown that many ncRNAs of the RNA-infrastructure are highly conserved, but little is known from non-model protists. In this study we have conducted a genome-scale survey of medium-length ncRNAs from the protozoan parasites Giardia intestinalis and Trichomonas vaginalis. Results We have identified the previously 'missing' Giardia RNase MRP RNA, which is a key ribozyme involved in pre-rRNA processing. We have also uncovered 18 new H/ACA box snoRNAs, expanding our knowledge of the H/ACA family of snoRNAs. Conclusions Results indicate that Giardia intestinalis and Trichomonas vaginalis, like their distant multicellular relatives, contain a rich infrastructure of RNA-based processing. From here we can investigate the evolution of RNA processing networks in eukaryotes. PMID:22053856

[Parasitic zoonotic disease agents in human and animal drinking water].

PubMed

Karanis, P

2000-08-01

Human- and veterinary important parasites of the subkingdom of protozoans and helminths infect humans and animals by ingestion of parasites in contaminated water. The parasites are excreted from the body of infected humans, livestock, zoo animals, companion animals or wild animals in the feces. Recreational waters, agricultural practices and wild animals serve as vehicles of transmission of the parasites in the water supplies. The following topics are addressed: a) the life cycles of parasitic diseases-causing agents with proven or potential transmission via water b) the development and the current research status of the analytical techniques for the detection of parasitic diseases-causing agents from water c) the occurrence of Cryptosporidium and Giardia in surface water supplies and in treated water d) the possible water sources and transmission ways of the parasites into the water supplies e) the behaviour and the possibilities for the removal or elimination of the parasites by water treatment.

Measurement of action spectra of light-activated processes

NASA Astrophysics Data System (ADS)

Ross, Justin; Zvyagin, Andrei V.; Heckenberg, Norman R.; Upcroft, Jacqui; Upcroft, Peter; Rubinsztein-Dunlop, Halina H.

2006-01-01

We report on a new experimental technique suitable for measurement of light-activated processes, such as fluorophore transport. The usefulness of this technique is derived from its capacity to decouple the imaging and activation processes, allowing fluorescent imaging of fluorophore transport at a convenient activation wavelength. We demonstrate the efficiency of this new technique in determination of the action spectrum of the light mediated transport of rhodamine 123 into the parasitic protozoan Giardia duodenalis.

Prevalence of Soil-Transmitted Helminthiases and Schistosomiasis in Preschool Age Children in Mwea Division, Kirinyaga South District, Kirinyaga County, and Their Potential Effect on Physical Growth

PubMed Central

Mkoji, Gerald M.

2017-01-01

Intestinal parasitic infections can significantly contribute to the burden of disease, may cause nutritional and energetic stress, and negatively impact the quality of life in low income countries of the world. This cross-sectional study done in Mwea irrigation scheme, in Kirinyaga, central Kenya, assessed the public health significance of soil-transmitted helminthiases (STH), schistosomiasis, and other intestinal parasitic infections, among 361 preschool age children (PSAC) through fecal examination, by measuring anthropometric indices, and through their parents/guardians, by obtaining sociodemographic information. Both intestinal helminth and protozoan infections were detected, and, among the soil-transmitted helminth parasites, there were Ascaris lumbricoides (prevalence, 3%), Ancylostoma duodenale (<1%), and Trichuris trichiura (<1%). Other intestinal helminths were Hymenolepis nana (prevalence, 3.6%) and Enterobius vermicularis (<1%). Schistosoma mansoni occurred at a prevalence of 5.5%. Interestingly, the protozoan, Giardia lamblia (prevalence, 14.7%), was the most common among the PSAC. Other protozoans were Entamoeba coli (3.9%) and Entamoeba histolytica (<1). Anthropometric indices showed evidence of malnutrition. Intestinal parasites were associated with hand washing behavior, family size, water purification, and home location. These findings suggest that G. lamblia infection and malnutrition may be significant causes of ill health among the PSAC in Mwea, and, therefore, an intervention plan is needed. PMID:29138640

Monitoring of Noxious Protozoa for Management of Natural Water Resources.

PubMed

Bahk, Young Yil; Cho, Pyo Yun; Ahn, Sung Kyu; Park, Sangjung; Jheong, Won Hwa; Park, Yun-Kyu; Shin, Ho-Joon; Lee, Sang-Seob; Rhee, Okjae; Kim, Tong-Soo

2018-04-01

Waterborne parasitic protozoa, particularly Giardia lamblia and Cryptosporidium spp., are common causes of diarrhea and gastroenteritis worldwide. The most frequently identified source of infestation is water, and exposure involves either drinking water or recreation in swimming pools or natural bodies of water. In practice, studies on Cryptosporidium oocysts and Giardia cysts in surface water are challenging owing to the low concentrations of these microorganisms because of dilution. In this study, a 3-year monitoring of Cryptosporidium parvum, Giardia lamblia , and Naegleria fowleri was conducted from August 2014 to June 2016 at 5 surface water sites including 2 lakes, 1 river, and 2 water intake plants. A total of 50 water samples of 40 L were examined. Cryptosporidium oocysts were detected in 22% of samples and Giardia cysts in 32%. Water at the 5 sampling sites was all contaminated with Cryptosporidium oocysts (0-36/L), Giardia cysts (0-39/L), or both. The geometric mean concentrations of Cryptosporidium and Giardia were 1.14 oocysts/L and 4.62 cysts/L, respectively. Thus, effective monitoring plans must take into account the spatial and temporal parameters of contamination because they affect the prevalence and distribution of these protozoan cysts in local water resources.

Bile Salt Hydrolase Activities: A Novel Target to Screen Anti-Giardia Lactobacilli?

PubMed Central

Allain, Thibault; Chaouch, Soraya; Thomas, Myriam; Travers, Marie-Agnès; Valle, Isabelle; Langella, Philippe; Grellier, Philippe; Polack, Bruno; Florent, Isabelle; Bermúdez-Humarán, Luis G.

2018-01-01

Giardia duodenalis is a protozoan parasite responsible for giardiasis, a disease characterized by intestinal malabsorption, diarrhea and abdominal pain in a large number of mammal species. Giardiasis is one of the most common intestinal parasitic diseases in the world and thus a high veterinary, and public health concern. It is well-established that some probiotic bacteria may confer protection against this parasite in vitro and in vivo and we recently documented the implication of bile-salt hydrolase (BSH)-like activities from strain La1 of Lactobacillus johnsonii as mediators of these effects in vitro. We showed that these activities were able to generate deconjugated bile salts that were toxic to the parasite. In the present study, a wide collection of lactobacilli strains from different ecological origins was screened to assay their anti-giardial effects. Our results revealed that the anti-parasitic effects of some of the strains tested were well-correlated with the expression of BSH-like activities. The two most active strains in vitro, La1 and Lactobacillus gasseri CNCM I-4884, were then tested for their capacity to influence G. duodenalis infection in a suckling mice model. Strikingly, only L. gasseri CNCM I-4884 strain was able to significantly antagonize parasite growth with a dramatic reduction of the trophozoites load in the small intestine. Moreover, this strain also significantly reduced the fecal excretion of Giardia cysts after 5 days of treatment, which could contribute to blocking the transmission of the parasite, in contrast of La1 where no effect was observed. This study represents a step toward the development of new prophylactic strategies to combat G. duodenalis infection in both humans and animals. PMID:29472903

Antiparasitic activity of diallyl trisulfide (Dasuansu) on human and animal pathogenic protozoa (Trypanosoma sp., Entamoeba histolytica and Giardia lamblia) in vitro.

PubMed

Lun, Z R; Burri, C; Menzinger, M; Kaminsky, R

1994-03-01

Garlic (Allium sativum L.) and one of its major components, allicin, have been known to have antibacterial and antifungal activity for a long time. Diallyl trisulfide is a chemically stable final transformation product of allicin which was synthesized in 1981 in China and used for treatment of bacterial, fungal and parasitic infections in man. The activity of diallyl trisulfide was investigated in several important protozoan parasites in vitro. The IC50 (concentration which inhibits metabolism or growth of parasites by 50%) for Trypanosoma brucei brucei, T.b. rhodesiense, T.b. gambiense, T. evansi, T. congolense and T. equiperdum was in the range of 0.8-5.5 micrograms/ml. IC50 values were 59 micrograms/ml for Entamoeba histolytica and 14 micrograms/ml for Giardia lamblia. The cytotoxicity of the compound was evaluated on two fibroblast cell lines (MASEF, Mastomys natalensis embryo fibroblast and HEFL-12, human embryo fibroblast) in vitro. The maximum tolerated concentration for both cell lines was 25 micrograms/ml. The results indicate that the compound has potential to be used for treatment of several human and animal parasitic diseases.

Hydrologic and Vegetative Removal of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii Surrogate Microspheres in Coastal Wetlands

PubMed Central

Hogan, Jennifer N.; Daniels, Miles E.; Watson, Fred G.; Oates, Stori C.; Miller, Melissa A.; Conrad, Patricia A.; Shapiro, Karen; Hardin, Dane; Dominik, Clare; Melli, Ann; Jessup, David A.

2013-01-01

Constructed wetland systems are used to reduce pollutants and pathogens in wastewater effluent, but comparatively little is known about pathogen transport through natural wetland habitats. Fecal protozoans, including Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii, are waterborne pathogens of humans and animals, which are carried by surface waters from land-based sources into coastal waters. This study evaluated key factors of coastal wetlands for the reduction of protozoal parasites in surface waters using settling column and recirculating mesocosm tank experiments. Settling column experiments evaluated the effects of salinity, temperature, and water type (“pure” versus “environmental”) on the vertical settling velocities of C. parvum, G. lamblia, and T. gondii surrogates, with salinity and water type found to significantly affect settling of the parasites. The mesocosm tank experiments evaluated the effects of salinity, flow rate, and vegetation parameters on parasite and surrogate counts, with increased salinity and the presence of vegetation found to be significant factors for removal of parasites in a unidirectional transport wetland system. Overall, this study highlights the importance of water type, salinity, and vegetation parameters for pathogen transport within wetland systems, with implications for wetland management, restoration efforts, and coastal water quality. PMID:23315738

Giardia duodenalis and Cryptosporidium occurrence in Australian sea lions (Neophoca cinerea) exposed to varied levels of human interaction

PubMed Central

Delport, Tiffany C.; Asher, Amy J.; Beaumont, Linda J.; Webster, Koa N.; Harcourt, Robert G.; Power, Michelle L.

2014-01-01

Giardia and Cryptosporidium are amongst the most common protozoan parasites identified as causing enteric disease in pinnipeds. A number of Giardia assemblages and Cryptosporidium species and genotypes are common in humans and terrestrial mammals and have also been identified in marine mammals. To investigate the occurrence of these parasites in an endangered marine mammal, the Australian sea lion (Neophoca cinerea), genomic DNA was extracted from faecal samples collected from wild populations (n = 271) in Southern and Western Australia and three Australian captive populations (n = 19). These were screened using PCR targeting the 18S rRNA of Giardia and Cryptosporidium. Giardia duodenalis was detected in 28 wild sea lions and in seven captive individuals. Successful sequencing of the 18S rRNA gene assigned 27 Giardia isolates to assemblage B and one to assemblage A, both assemblages commonly found in humans. Subsequent screening at the gdh and β-giardin loci resulted in amplification of only one of the 35 18S rRNA positive samples at the β-giardin locus. Sequencing at the β-giardin locus assigned the assemblage B 18S rRNA confirmed isolate to assemblage AI. The geographic distribution of sea lion populations sampled in relation to human settlements indicated that Giardia presence in sea lions was highest in populations less than 25 km from humans. Cryptosporidium was not detected by PCR screening in either wild colonies or captive sea lion populations. These data suggest that the presence of G. duodenalis in the endangered Australian sea lion is likely the result of dispersal from human sources. Multilocus molecular analyses are essential for the determination of G. duodenalis assemblages and subsequent inferences on transmission routes to endangered marine mammal populations. PMID:25426423

Giardia duodenalis and Cryptosporidium occurrence in Australian sea lions (Neophoca cinerea) exposed to varied levels of human interaction.

PubMed

Delport, Tiffany C; Asher, Amy J; Beaumont, Linda J; Webster, Koa N; Harcourt, Robert G; Power, Michelle L

2014-12-01

Giardia and Cryptosporidium are amongst the most common protozoan parasites identified as causing enteric disease in pinnipeds. A number of Giardia assemblages and Cryptosporidium species and genotypes are common in humans and terrestrial mammals and have also been identified in marine mammals. To investigate the occurrence of these parasites in an endangered marine mammal, the Australian sea lion (Neophoca cinerea), genomic DNA was extracted from faecal samples collected from wild populations (n = 271) in Southern and Western Australia and three Australian captive populations (n = 19). These were screened using PCR targeting the 18S rRNA of Giardia and Cryptosporidium. Giardia duodenalis was detected in 28 wild sea lions and in seven captive individuals. Successful sequencing of the 18S rRNA gene assigned 27 Giardia isolates to assemblage B and one to assemblage A, both assemblages commonly found in humans. Subsequent screening at the gdh and β-giardin loci resulted in amplification of only one of the 35 18S rRNA positive samples at the β-giardin locus. Sequencing at the β-giardin locus assigned the assemblage B 18S rRNA confirmed isolate to assemblage AI. The geographic distribution of sea lion populations sampled in relation to human settlements indicated that Giardia presence in sea lions was highest in populations less than 25 km from humans. Cryptosporidium was not detected by PCR screening in either wild colonies or captive sea lion populations. These data suggest that the presence of G. duodenalis in the endangered Australian sea lion is likely the result of dispersal from human sources. Multilocus molecular analyses are essential for the determination of G. duodenalis assemblages and subsequent inferences on transmission routes to endangered marine mammal populations.

Presence of Cryptosporidium spp. and Giardia duodenalis in Drinking Water Samples in the North of Portugal

PubMed Central

Moreira, Maria João; Soares, Sónia; de Lurdes Delgado, Maria; Figueiredo, João; Silva, Elisabete; Castro, António; Cosa, José Manuel Correida Da

2010-01-01

Cryptosporidium and Giardia are 2 protozoan parasites responsible for waterborne diseases outbreaks worldwide. In order to assess the prevalence of these protozoans in drinking water samples in the northern part of Portugal and the risk of human infection, we have established a long term program aiming at pinpointing the sources of surface water, drinking water, and environmental contamination, working with the water-supply industry. Total 43 sources of drinking water samples were selected, and a total of 167 samples were analyzed using the Method 1623. Sensitivity assays regarding the genetic characterization by PCR and sequencing of the genes, 18S SSU rRNA, for Cryptosporidium spp. and β,-giardin for G. duodenalis were set in the laboratory. According to the defined criteria, molecular analysis was performed over 4 samples. Environmental stages of the protozoa were detected in 25.7% (43 out of 167) of the water samples, 8.4% (14 out of 167) with cysts of Giardia, 10.2% (17 out of 167) with oocysts of Cryptosporidium and 7.2% (12 out of 167) for both species. The mean concentrations were 0.1-12.7 oocysts of Cryptosporidium spp. per 10 L and 0.1-108.3 cysts of Giardia duodenalis per 10 L. Our results suggest that the efficiency in drinking water plants must be ameliorated in their efficiency in reducing the levels of contamination. We suggest the implementation of systematic monitoring programs for both protozoa. To authors' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in drinking water samples in the northern part of Portugal. PMID:20333284

Imaging and identification of waterborne parasites using a chip-scale microscope.

PubMed

Lee, Seung Ah; Erath, Jessey; Zheng, Guoan; Ou, Xiaoze; Willems, Phil; Eichinger, Daniel; Rodriguez, Ana; Yang, Changhuei

2014-01-01

We demonstrate a compact portable imaging system for the detection of waterborne parasites in resource-limited settings. The previously demonstrated sub-pixel sweeping microscopy (SPSM) technique is a lens-less imaging scheme that can achieve high-resolution (<1 µm) bright-field imaging over a large field-of-view (5.7 mm×4.3 mm). A chip-scale microscope system, based on the SPSM technique, can be used for automated and high-throughput imaging of protozoan parasite cysts for the effective diagnosis of waterborne enteric parasite infection. We successfully imaged and identified three major types of enteric parasite cysts, Giardia, Cryptosporidium, and Entamoeba, which can be found in fecal samples from infected patients. We believe that this compact imaging system can serve well as a diagnostic device in challenging environments, such as rural settings or emergency outbreaks.

Larrea tridentata: A novel source for anti-parasitic agents active against Entamoeba histolytica, Giardia lamblia and Naegleria fowleri.

PubMed

Bashyal, Bharat; Li, Linfeng; Bains, Trpta; Debnath, Anjan; LaBarbera, Daniel V

2017-08-01

Protozoan parasites infect and kill millions of people worldwide every year, particularly in developing countries where access to clean fresh water is limited. Among the most common are intestinal parasites, including Giardia lamblia and Entamoeba histolytica. These parasites wreak havoc on the epithelium lining the small intestines (G. lamblia) and colon (E. histolytica) causing giardiasis and amebiasis, respectively. In addition, there are less common but far more deadly pathogens such as Naegleria fowleri that thrive in warm waters and infect the central nervous systems of their victims via the nasal passages. Despite their prevalence and associated high mortality rates, there remains an unmet need to identify more effective therapeutics for people infected with these opportunistic parasites. To address this unmet need, we have surveyed plants and traditional herbal medicines known throughout the world to identify novel antiparasitic agents with activity against G. lamblia, E. histolytica, and N. fowleri. Herein, we report Larrea tridentata, known as creosote bush, as a novel source for secondary metabolites that display antiparasitic activity against all three pathogens. This report also characterizes the lignan compound classes, nordihydroguairetic acid and demethoxyisoguaiacin, as novel antiparasitic lead agents to further develop more effective drug therapy options for millions of people worldwide.

Larrea tridentata: A novel source for anti-parasitic agents active against Entamoeba histolytica, Giardia lamblia and Naegleria fowleri

PubMed Central

Bains, Trpta; Debnath, Anjan

2017-01-01

Protozoan parasites infect and kill millions of people worldwide every year, particularly in developing countries where access to clean fresh water is limited. Among the most common are intestinal parasites, including Giardia lamblia and Entamoeba histolytica. These parasites wreak havoc on the epithelium lining the small intestines (G. lamblia) and colon (E. histolytica) causing giardiasis and amebiasis, respectively. In addition, there are less common but far more deadly pathogens such as Naegleria fowleri that thrive in warm waters and infect the central nervous systems of their victims via the nasal passages. Despite their prevalence and associated high mortality rates, there remains an unmet need to identify more effective therapeutics for people infected with these opportunistic parasites. To address this unmet need, we have surveyed plants and traditional herbal medicines known throughout the world to identify novel antiparasitic agents with activity against G. lamblia, E. histolytica, and N. fowleri. Herein, we report Larrea tridentata, known as creosote bush, as a novel source for secondary metabolites that display antiparasitic activity against all three pathogens. This report also characterizes the lignan compound classes, nordihydroguairetic acid and demethoxyisoguaiacin, as novel antiparasitic lead agents to further develop more effective drug therapy options for millions of people worldwide. PMID:28793307

Simultaneous detection of the protozoan parasites Toxoplasma, Cryptosporidium and Giardia in food matrices and their persistence on basil leaves.

PubMed

Hohweyer, Jeanne; Cazeaux, Catherine; Travaillé, Emmanuelle; Languet, Emilie; Dumètre, Aurélien; Aubert, Dominique; Terryn, Christine; Dubey, Jitender P; Azas, Nadine; Houssin, Maryline; Loïc, Favennec; Villena, Isabelle; La Carbona, Stéphanie

2016-08-01

Toxoplasma gondii, Cryptosporidium spp. and Giardia intestinalis are emerging pathogen parasites in the food domain. However, without standardized methods for their detection in food matrices, parasitic foodborne outbreaks remain neglected. In this study, a new immunomagnetic separation assay (IMS Toxo) targeting the oocyst's wall of T. gondii was developed using a specific purified monoclonal antibody. Performance of this IMS Toxo coupled to microscopic and qPCR analyses was evaluated in terms of limit of detection (LOD) and recovery rate (RR) on: i) simple matrix (LOD = 5 oocysts; RR between 5 and 56%); ii) raspberries and basil (LOD = 33 oocysts/g; RR between 0.2 and 35%). Finally, to simultaneously extract the three protozoa from these food matrices, T. gondii oocysts were directly concentrated (without IMS Toxo) from the supernatant of the IMS of Cryptosporidium and Giardia (oo)cysts. This strategy associated to qPCR detection led to LOD <1 to 3 (oo)cysts/g and RR between 2 and 35%. This procedure was coupled to RT-qPCR analyses and showed that the three protozoa persisted on the leaves of basil and remained viable following storage at 4 °C for 8 days. These data strengthen the need to consider these protozoa in food safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic Diversity of Giardia duodenalis: Multilocus Genotyping Reveals Zoonotic Potential between Clinical and Environmental Sources in a Metropolitan Region of Brazil

PubMed Central

Durigan, Mauricio; Abreu, Aluana Gonçalves; Zucchi, Maria Imaculada; Franco, Regina Maura Bueno; de Souza, Anete Pereira

2014-01-01

Background Giardia duodenalis is a flagellate protozoan that parasitizes humans and several other mammals. Protozoan contamination has been regularly documented at important environmental sites, although most of these studies were performed at the species level. There is a lack of studies that correlate environmental contamination and clinical infections in the same region. The aim of this study is to evaluate the genetic diversity of a set of clinical and environmental samples and to use the obtained data to characterize the genetic profile of the distribution of G. duodenalis and the potential for zoonotic transmission in a metropolitan region of Brazil. Methodology/Principal Findings The genetic assemblages and subtypes of G. duodenalis isolates obtained from hospitals, a veterinary clinic, a day-care center and important environmental sites were determined via multilocus sequence-based genotyping using three unlinked gene loci. Cysts of Giardia were detected at all of the environmental sites. Mixed assemblages were detected in 25% of the total samples, and an elevated number of haplotypes was identified. The main haplotypes were shared among the groups, and new subtypes were identified at all loci. Ten multilocus genotypes were identified: 7 for assemblage A and 3 for assemblage B. Conclusions/Significance There is persistent G. duodenalis contamination at important environmental sites in the city. The identified mixed assemblages likely represent mixed infections, suggesting high endemicity of Giardia in these hosts. Most Giardia isolates obtained in this study displayed zoonotic potential. The high degree of genetic diversity in the isolates obtained from both clinical and environmental samples suggests that multiple sources of infection are likely responsible for the detected contamination events. The finding that many multilocus genotypes (MLGs) and haplotypes are shared by different groups suggests that these sources of infection may be related and indicates that there is a notable risk of human infection caused by Giardia in this region. PMID:25536055

Opportunistic Parasites among Immunosuppressed Children in Minia District, Egypt

PubMed Central

Ahmad, Azza K.; Ali, Basma A.; Moslam, Fadia A.

2012-01-01

A total of 450 stool samples were collected from inpatient and outpatient clinics of Pediatric Department, Minia University Hospital, Minia District, Egypt. Two groups of patients were studied, including 200 immunosuppressed and 250 immunocompetent children. Stool samples were subjected to wet saline and iodine mounts. A concentration technique (formol-ether sedimentation method) was carried out for stool samples diagnosed negative by wet saline and iodine mounts. Samples were stained by 2 different methods; acid fast stain (modified Ziehl-Neelsen stain) and Giemsa stain. Total 188 cases (94%) were diagnosed positive for parasitic infections among immunosuppressed children, whereas 150 cases (60%) were positive in immunocompetent children (P<0.0001). The most common protozoan infection in immunosuppressed group was Cryptosporidium parvum (60.2%), followed by Blastocystis hominis (12.1%), Isospora belli (9.7%), and Cyclospora caytenensis (7.8%). On the other hand, Entamoeba histolytica (24.6%) and Giardia lamblia (17.6%) were more common than other protozoans in immunocompetent children. PMID:22451735

Detection of Giardia intestinalis infections in Polish soldiers deployed to Afghanistan.

PubMed

Korzeniewski, Krzysztof; Konior, Monika; Augustynowicz, Alina; Lass, Anna; Kowalska, Ewa

2016-01-01

Members of the Polish Military Contingent (PMC) have been stationed in Afghanistan since 2002. They typically serve in areas characterised by low standards of sanitation which often leads to the development of food- and waterborne diseases. The aim of the study was to evaluate the prevalence of Giardia intestinalis infections among Polish soldiers deployed to Afghanistan. The research study was conducted as part of a programme for prevention of parasitic diseases of the gastrointestinal tract run by the Polish Armed Forces. The study was carried out in August 2011; it involved 630 asymptomatic Polish soldiers serving in the Forward Operational Base (FOB) Ghazni in eastern Afghanistan. Stool specimens obtained from members of the PMC were first tested in FOB Ghazni (detection of Giardia intestinalis by Rida Quick Giardia immunochromatographic tests and Ridascreen Giardia immunoenzymatic tests - single samples). Next, the same biological material and two other faecal specimens fixed in 10% formalin were transported to the Military Institute of Medicine in Poland, where they were tested for Giardia intestinalis under light microscopy (direct smear, decantation in distilled water). Parasitological tests performed under light microscopy showed that 2.7% (17/630) of the study group were infected with Giardia intestinalis. Some of these results were confirmed by immunochromatographic tests (6/630). In contrast, immunoenzymatic tests (ELISA) demonstrated a significantly higher detection rate reaching 18.1% (114/630). Immunoenzymatic tests confirmed all the positive results given by light microscopy and by immunochromatographic tests. The prevalence rate of Giardia intestinalis infections in Polish soldiers deployed to Afghanistan was found to be high. Microscopic methods exhibit low sensitivity and therefore may result in the underestimation of the true parasite prevalence. Immunoenzymatic tests (ELISA) showing a much higher sensitivity in comparison to light microscopy and immunochromatographic tests ought to be applied in screening for intestinal protozoan infections in areas characterised by harsh environmental conditions.

Identification and genotyping of Giardia spp. and Cryptosporidium spp. isolates in aquatic birds in the Salburua wetlands, Álava, Northern Spain.

PubMed

Cano, Lourdes; de Lucio, Aida; Bailo, Begoña; Cardona, Guillermo A; Muadica, Aly Salimo Omar; Lobo, Luis; Carmena, David

2016-05-15

Aquatic birds are known to be suitable hosts for a number of avian-specific species and genotypes of the enteric protozoan parasites Giardia and Cryptosporidium. Waterbirds have also been reported as sporadic carriers of species of both pathogens from human or domestic animal origin via environmental contamination. Because aquatic birds can shed substantial amounts of infective Giardia and Cryptosporidium (oo)cysts to the environment including surface waters intended for human consumption, this situation may pose a potential risk of waterborne zoonotic disease. A total of 265 waterbird faecal samples were collected from May 2014 to June 2015 at Salburua (Álava), one of the most valued continental wetlands in northern Spain. The detection of Giardia oocyst and Cryptosporidium oocysts was carried out by direct fluorescence microscopy and molecular (PCR and sequence analysis) methods targeting the small subunit ribosomal RNA gene of the parasites. Typing of Giardia duodenalis isolates at the sub-assemblage level was based on the specific amplification and sequencing of a partial fragment of the glutamate dehydrogenase gene. Overall, Giardia cysts and Cryptosporidium oocysts were detected in 22 (8.3%) and 6 (2.3%), respectively, of the 265 faecal samples analysed. The two only Giardia isolates characterized (one novel, one known) were assigned to the sub-assemblage BIV of G. duodenalis, none of them previously reported in Spanish human isolates. This finding raises doubts about the actual origin of the infection and whether waterbirds may serve as potential source of infective Giardia cysts to humans via waterborne transmission or through direct contact. The six Cryptosporidium isolates obtained were characterized as avian genotype III (n=4), duck genotype b (n=1), and goose genotype Id (n=1), all considered avian-specific and therefore of negligible risk of zoonotic infection. Copyright © 2016 Elsevier B.V. All rights reserved.

[Optimization of Cryptosporidium and Giardia detection in water environment using automatic elution station Filta-Max xpress].

PubMed

Matuszewska, Renata; Szczotko, Maciej; Krogulska, Bozena

2012-01-01

The presence of parasitic protozoa in drinking water is mostly a result of improperly maintened the water treatment process. Currently, in Poland the testing of Cryptosporidium and Giardia in water as a part of routine monitoring of water is not perform. The aim of this study was the optimization of the method of Cryptosporidium and Giardia detection in water according to the main principles of standard ISO 15553:2006 and using Filta-Max xpress automatic elution station. Preliminary tests were performed on the samples contaminated with oocysts and cysts of reference strains of both parasitic protozoa. Further studies were carried out on environmental samples of surface water sampled directly from the intakes of water (21 samples from Vistula River and 8 samples from Zegrzynski Lake). Filtration process and samples volume reducing were performed using an automatic elution system Filta-Max xpress. Next, samples were purified during immunomagnetic separation process (IMS). Isolated cysts and oocysts were stained with FITC and DAPI and than the microscopic observation using an epifluorescence microscope was carried out. Recovery of parasite protozoa in all contaminated water samples after 9-cycles elution process applied was mean 60.6% for Cryptosporidium oocysts and 36.1% for Giardia cysts. Studies on the environmental surface water samples showed the presence of both parasitic protozoa. Number of detected Giardia cysts ranged from 1.0/10 L up to 4.5/10 L in samples from Zegrzynski Lake and from 1.0/10 L up to 38.9/10 L in samples from Vistula River. Cryptosporidium oocysts were present in 50% of samples from the Zegrzynski Lake and in 47.6% of samples from the Vistula River, and their number in both cases was similar and ranged from 0.5 up to 2.5 oocyst/10 L. The results show that applied procedure is appropriate for detection the presence of parasitic protosoan in water, but when water contains much amount of inorganic matter and suspended solids test method have to be modified like subsamples preparation and filtration process speed reduction. The applied method with the modification using Filta-Max xpress system can be useful for the routine monitoring of water. Detection of Cryptosporidium and Giardia in all samples of water taken from the intakes of surface water shows the possibility oftransfering of the protozoan cysts into the water intended for the consumption, therefore the testing of Cryptosporidium and Giardia should be included into the monitoring of water.

Detection of selected intestinal helminths and protozoa at Hospital Universiti Sains Malaysia using multiplex real-time PCR.

PubMed

Basuni, M; Mohamed, Z; Ahmad, M; Zakaria, N Z; Noordin, R

2012-09-01

Intestinal parasites are the causative agents of a number of important human infections in developing countries. The objective of this study was to determine the prevalence of selected helminths and protozoan infections among patients admitted with gastrointestinal disorders at Hospital Universiti Sains Malaysia, Kelantan, Malaysia using multiplex real-time PCR. In addition microscopic examination was also performed following direct smear, zinc sulphate concentration and Kato-Katz thick smear techniques; and the presence of protozoan parasites was confirmed using trichrome and acid-fast stains. Of the 225 faecal samples analysed, 26.2% were positive for intestinal parasites by the multiplex real-time PCR, while 5.3% were positive by microscopy. As compared to microscopy, the multiplex real-time PCR detected 5.8 and 4.5 times more positives for the selected helminth and protozoan infections respectively. Among the selected helminths detected in this study, hookworm was the most prevalent by real-time PCR, while Ascaris lumbricoides was detected the most by microscopy. Meanwhile, among the selected protozoa detected in this study, Entamoeba histolytica was the most prevalent by real-time PCR, however microscopy detected equal number of cases with E. histolytica and Giardia lamblia. This study showed that real-time PCR can be used to obtain a more accurate prevalence data on intestinal helminths and protozoa.

Occurrence and removal efficiency of parasitic protozoa in Swedish wastewater treatment plants.

PubMed

Berglund, Björn; Dienus, Olaf; Sokolova, Ekaterina; Berglind, Emma; Matussek, Andreas; Pettersson, Thomas; Lindgren, Per-Eric

2017-11-15

Giardia intestinalis, Cryptosporidium spp., Entamoeba histolytica and Dientamoeba fragilis are parasitic protozoa and causative agents of gastroenteritis in humans. G. intestinalis and Cryptosporidium spp. in particular are the most common protozoa associated with waterborne outbreaks in high-income countries. Surveillance of protozoan prevalence in wastewater and evaluation of wastewater treatment removal efficiencies of protozoan pathogens is therefore imperative for assessment of human health risk. In this study, influent and effluent wastewater samples from three wastewater treatment plants in Sweden were collected over nearly one year and assessed for prevalence of parasitic protozoa. Quantitative real-time PCR using primers specific for the selected protozoa Cryptosporidium spp., G. intestinalis, E. histolytica, Entamoeba dispar and D. fragilis was used for protozoan DNA detection and assessment of wastewater treatment removal efficiencies. Occurrence of G. intestinalis, E. dispar and D. fragilis DNA was assessed in both influent (44, 30 and 39 out of 51 samples respectively) and effluent wastewater (14, 9 and 33 out of 51 samples respectively) in all three wastewater treatment plants. Mean removal efficiencies of G. intestinalis, E. dispar and D. fragilis DNA quantities, based on all three wastewater treatment plants studied varied between 67 and 87%, 37-75% and 20-34% respectively. Neither E. histolytica nor Cryptosporidium spp. were detected in any samples. Overall, higher quantities of protozoan DNA were observed from February to June 2012. The high prevalence of protozoa in influent wastewater indicates the need for continued monitoring of these pathogens in wastewater-associated aquatic environments to minimise the potential risk for human infection. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular epidemiology of Giardia and Cryptosporidium infections.

PubMed

Thompson, R C A; Ash, A

2016-06-01

Giardia and Cryptosporidium are ubiquitous enteric protozoan pathogens of vertebrates. Although recognised as the aetiological agents of disease in humans and domestic animals for many years, fundamental questions concerning their ecology have been unresolved. Molecular tools have helped to better understand their genetic diversity and in so doing have helped to resolve questions about their transmission patterns and associated impacts on public health. However, the value of molecular tools is often complicated by questions concerning their applications, interpretation of results and terminology. Taxonomic issues have, until recently, made it difficult to determine the epidemiology of infections with both Giardia and Cryptosporidium. Similarly, improved understanding of their respective phylogenetic relationships has helped to resolve questions about zoonotic potential and distribution in wildlife. In the case of Cryptosporidium, imaging technologies have complemented phylogenetic studies in demonstrating the parasite's affinities with gregarine protozoa and have further supported its extracellular developmental capability and potential role as an environmental pathogen. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

IL-17A promotes protective IgA responses and expression of other potential effectors against the lumen-dwelling enteric parasite Giardia.

PubMed

Dann, Sara M; Manthey, Carolin F; Le, Christine; Miyamoto, Yukiko; Gima, Lauren; Abrahim, Andrew; Cao, Anthony T; Hanson, Elaine M; Kolls, Jay K; Raz, Eyal; Cong, Yingzi; Eckmann, Lars

2015-09-01

Giardia lamblia is a leading protozoan cause of diarrheal disease worldwide. It colonizes the lumen and epithelial surface of the small intestine, but does not invade the mucosa. Acute infection causes only minimal mucosal inflammation. Effective immune defenses exist, yet their identity and mechanisms remain incompletely understood. Interleukin (IL)-17A has emerged as an important cytokine involved in inflammation and antimicrobial defense against bacterial pathogens at mucosal surfaces. In this study, we demonstrate that IL-17A has a crucial function in host defense against Giardia infection. Using murine infection models with G. muris and G. lamblia, we observed marked and selective induction of intestinal IL-17A with peak expression after 2 weeks. Th17 cells in the lamina propria and innate immune cells in the epithelial compartment of the small intestine were responsible for the IL-17A response. Experiments in gene-targeted mice revealed that the cytokine, and its cognate receptor IL-17RA, were required for eradication of the parasite. The actions of the cytokine were mediated by hematopoietic cells, and were required for the transport of IgA into the intestinal lumen, since IL-17A deficiency led to marked reduction of fecal IgA levels, as well as for increased intestinal expression of several other potential effectors, including β-defensin 1 and resistin-like molecule β. In contrast, intestinal hypermotility, another major antigiardial defense mechanism, was not impacted by IL-17A loss. Taken together, these findings demonstrate that IL-17A and IL-17 receptor signaling are essential for intestinal defense against the important lumen-dwelling intestinal parasite Giardia. Copyright © 2015 Elsevier Inc. All rights reserved.

Cryptosporidium and Giardia in surface water: a case study from Michigan, USA to inform management of rural water systems.

PubMed

Dreelin, Erin A; Ives, Rebecca L; Molloy, Stephanie; Rose, Joan B

2014-10-14

Cryptosporidium and Giardia pose a threat to human health in rural environments where water supplies are commonly untreated and susceptible to contamination from agricultural animal waste/manure, animal wastewater, septic tank effluents and septage. Our goals for this paper are to: (1) explore the prevalence of these protozoan parasites, where they are found, in what quantities, and which genotypes are present; (2) examine relationships between disease and land use comparing human health risks between rural and urban environments; and (3) synthesize available information to gain a better understanding of risk and risk management for rural water supplies. Our results indicate that Cryptosporidium and Giardia were more prevalent in rural versus urban environments based on the number of positive samples. Genotyping showed that both the human and animal types of the parasites are found in rural and urban environments. Rural areas had a higher incidence of disease compared to urban areas based on the total number of disease cases. Cryptosporidiosis and giardiasis were both positively correlated (p < 0.001) with urban area, population size, and population density. Finally, a comprehensive strategy that creates knowledge pathways for data sharing among multiple levels of management may improve decision-making for protecting rural water supplies.

Cryptosporidium and Giardia in Surface Water: A Case Study from Michigan, USA to Inform Management of Rural Water Systems

PubMed Central

Dreelin, Erin A.; Ives, Rebecca L.; Molloy, Stephanie; Rose, Joan B.

2014-01-01

Cryptosporidium and Giardia pose a threat to human health in rural environments where water supplies are commonly untreated and susceptible to contamination from agricultural animal waste/manure, animal wastewater, septic tank effluents and septage. Our goals for this paper are to: (1) explore the prevalence of these protozoan parasites, where they are found, in what quantities, and which genotypes are present; (2) examine relationships between disease and land use comparing human health risks between rural and urban environments; and (3) synthesize available information to gain a better understanding of risk and risk management for rural water supplies. Our results indicate that Cryptosporidium and Giardia were more prevalent in rural versus urban environments based on the number of positive samples. Genotyping showed that both the human and animal types of the parasites are found in rural and urban environments. Rural areas had a higher incidence of disease compared to urban areas based on the total number of disease cases. Cryptosporidiosis and giardiasis were both positively correlated (p < 0.001) with urban area, population size, and population density. Finally, a comprehensive strategy that creates knowledge pathways for data sharing among multiple levels of management may improve decision-making for protecting rural water supplies. PMID:25317981

Cryptosporidium and Giardia in tropical recreational marine waters contaminated with domestic sewage: estimation of bathing-associated disease risks.

PubMed

Betancourt, Walter Q; Duarte, Diana C; Vásquez, Rosa C; Gurian, Patrick L

2014-08-15

Sewage is a major contributor to pollution problems involving human pathogens in tropical coastal areas. This study investigated the occurrence of intestinal protozoan parasites (Giardia and Cryptosporidium) in tropical recreational marine waters contaminated with sewage. The potential risks of Cryptosporidium and Giardia infection from recreational water exposure were estimated from the levels of viable (oo) cysts (DIC+, DAPI+, PI-) found in near-shore swimming areas using an exponential dose response model. A Monte Carlo uncertainty analysis was performed in order to determine the probability distribution of risks. Microbial indicators of recreational water quality (enterococci, Clostridium perfringens) and genetic markers of sewage pollution (human-specific Bacteroidales marker [HF183] and Clostridium coccoides) were simultaneously evaluated in order to estimate the extent of water quality deterioration associated with human wastes. The study revealed the potential risk of parasite infections via primary contact with tropical marine waters contaminated with sewage; higher risk estimates for Giardia than for Cryptosporidium were found. Mean risks estimated by Monte Carlo were below the U.S. EPA upper bound on recreational risk of 0.036 for cryptosporidiosis and giardiasis for both children and adults. However, 95th percentile estimates for giardiasis for children exceeded the 0.036 level. Environmental surveillance of microbial pathogens is crucial in order to control and eradicate the effects that increasing anthropogenic impacts have on marine ecosystems and human health. Copyright © 2014 Elsevier Ltd. All rights reserved.

Occurrence, genotyping, and health risk of Cryptosporidium and Giardia in recreational lakes in Tianjin, China.

PubMed

Xiao, Shumin; Yin, Pengna; Zhang, Yan; Zhao, Xiaoyun; Sun, Liping; Yuan, Hongying; Lu, Jingfang; Hu, Sike

2018-05-10

Cryptosporidium and Giardia are critical parasites in the etiology of diarrhea worldwide, and often cause waterborne outbreaks. The presence of Cryptosporidium and Giardia in recreational lakes was investigated with molecular characterization, and a comprehensive quantitative microbial risk assessment (QMRA) of protozoan infections was performed, considering multiple exposure pathways, differences in age, sex, and disease severity, and the genotypes of the protozoa. Forty-three (82.7%) and 51 (98.1%) water samples were positive for Cryptosporidium oocysts and Giardia cysts, respectively, with average counts of 3.65 oocysts/10 L and 12.58 cysts/10 L, respectively. Six Cryptosporidium species and three Giardia lamblia assemblages were confirmed with molecular analyses. The protozoan concentration was significantly associated with water turbidity, but not with the total coliform numbers. Swimming in the lakes entailed the highest incidence risk of 5.72 × 10 -4 per person per year (pppy) (95% confidence interval (CI): 0.03-43.33 × 10 -4 ) for Cryptosporidium and 4.04 × 10 -4 pppy (95% CI: 0.01-32.66 × 10 -4 ) for Giardia, whereas wading entailed the lowest risk (2.20 × 10 -4 and 1.70 × 10 -4 pppy, respectively). The annual burdens attributable to recreational-water-associated cryptosporidiosis and giardiasis were 3.44 (95% CI: 0.04-23.51) and 1.81 (95% CI: 0.01-12.96) disability-adjusted life years per 1,000,000 individuals per year, respectively. Children were more likely to have an individual disease burden than adults, and males were more likely than females. Sensitivity analysis highlighted the great importance of controlling the proportion of exposed individuals and reducing the frequency of exposure. The methodology and results of this study will allow us to better evaluate and reduce the burden of Cryptosporidium and/or Giardia infections associated with recreational water use in China and other countries. Copyright © 2018 Elsevier Ltd. All rights reserved.

Molecular Characterization of Giardia duodenalis in Children in Kenya.

PubMed

Mbae, C; Mulinge, E; Guleid, F; Wainaina, J; Waruru, A; Njiru, Z K; Kariuki, S

2016-03-22

Giardia duodenalis is an important intestinal protozoan in humans worldwide with high infection rates occurring in densely populated and low resource settings. The parasite has been recorded to cause diarrhea in children. This study was carried out to identify G. duodenalis assemblages and sub-assemblages in children presenting with diarrhea in Kenya. A total of 2112 faecal samples were collected from children aged ≤ 5 years and screened for the presence of Giardia cysts using microscopy. A total of 96 (4.5%) samples were identified as Giardia positive samples and were genotyped using glutamate dehydrogenase (gdh), triose phosphate isomerase (tpi) and β-giardin loci. The three markers successfully genotyped 72 isolates and grouped 2 (1.4) isolates as Assemblage A, 64 (88.9) as Assemblage B and 7 (9.7%) consisted of mixed infections with assemblage A and B. A further analysis of 50 isolates using GDH Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP) categorized 2 assemblage A isolates as sub-assemblage AII while 6 and 14 assemblage B isolates were categorized into sub-assemblage BIII and BIV respectively. A mixed infection with sub-assemblage BIII and BIV was recorded in 28 isolates. Over half (55.6%) of Giardia infections were recorded among the children between 13 to 48 months old. This paper reports the first data on the assemblages and sub-assemblages of Giardia duodenalis in children representing with diarrhea in Kenya.

Ecology of the gastrointestinal parasites of Colobus vellerosus at Boabeng-Fiema, Ghana: possible anthropozoonotic transmission.

PubMed

Teichroeb, Julie A; Kutz, Susan J; Parkar, Unaiza; Thompson, R C Andrew; Sicotte, Pascale

2009-11-01

Parasite richness and prevalence in wild animals can be used as indicators of population and ecosystem health. In this study, the gastrointestinal parasites of ursine colobus monkeys (Colobus vellerosus) at the Boabeng-Fiema Monkey Sanctuary (BFMS), Ghana, were investigated. BFMS is a sacred grove where monkeys and humans have long lived in relatively peaceful proximity. Fecal samples (n = 109) were collected opportunistically from >27 adult and subadult males in six bisexual groups and one all-male band from July 2004 to August 2005. Using fecal floatation, we detected three protozoans (two Entamoeba sp., Isospora sp.), five nematodes (Ascaris sp., Enterobius sp., Trichuris sp., two strongyle sp.), and one digenean trematode. Using fluorescein labeled antibodies, we detected an additional protozoan (Giardia sp.), and with PCR techniques, we characterized this as G. duodenalis Assemblage B and also identified a protistan (Blastocystis sp., subtype 2). The most prevalent parasite species were G. duodenalis and Trichuris sp. Parasites were more prevalent in the long wet season than the long dry. Parasite prevalence did not vary by age, and average parasite richness did not differ by rank for males whose status remained unchanged. However, males that changed rank tended to show higher average parasite richness when they were lower ranked. Individuals that spent more time near human settlements had a higher prevalence of Isospora sp. that morphologically resembled the human species I. belli. The presence of this parasite and G. duodenalis Assemblage B indicates possible anthropozoonotic and/or zoonotic transmission between humans and colobus monkeys at this site.

Minimal infectious doses and prepatent periods in Giardia muris, Spironucleus muris and Tritrichomonas muris.

PubMed

Stachan, R; Kunstýr, I

1983-12-01

The minimal infectious doses (MID) of Giardia muris cysts, Spironucleus muris cysts and Tritrichomonas muris pseudocysts for athymic mice were determined. A novel micromanipulator-aided technique was developed for selecting small exact numbers of specified fresh or old cysts/pseudocysts from a faecal homogenate. This technique can also be of value in manipulating protozoan parasites of any particular species. Only fresh cysts/pseudocysts, which appeared bright under phase contrast optics, were infectious. Older cysts and pseudocysts which appeared dark in phase contrast were not infectious. The MID for three murine intestinal flagellates addressed above were: 10 (between 5 and 20), 1 and 5 cysts/pseudocysts respectively. Corresponding prepatent periods (PP) were 8, 5 and 10 days. A relation was evident between the infectious dose and the PP: The prepatent period shortened with an increased infectious dose.

Giardia muris Infection in Mice Is Associated with a Protective Interleukin 17A Response and Induction of Peroxisome Proliferator-Activated Receptor Alpha

PubMed Central

Dreesen, Leentje; De Bosscher, Karolien; Grit, Grietje; Staels, Bart; Lubberts, Erik; Bauge, Eric

2014-01-01

The protozoan parasite Giardia duodenalis (Giardia lamblia) is one of the most commonly found intestinal pathogens in mammals, including humans. In the current study, a Giardia muris-mouse model was used to analyze cytokine transcription patterns and histological changes in intestinal tissue at different time points during infection in C57BL/6 mice. Since earlier work revealed the upregulation of peroxisome proliferator-activated receptors (PPARs) in Giardia-infected calves, a second aim was to investigate the potential activation of PPARs in the intestines of infected mice. The most important observation in all mice was a strong upregulation of il17a starting around 1 week postinfection. The significance of interleukin 17A (IL-17A) in orchestrating a protective immune response was further demonstrated in an infection trial or experiment using IL-17 receptor A (IL-17RA) knockout (KO) mice: whereas in wild-type (WT) mice, cyst secretion dropped significantly after 3 weeks of infection, the IL-17RA KO mice were unable to clear the infection. Analysis of the intestinal response further indicated peroxisome proliferator-activated receptor alpha (PPARα) induction soon after the initial contact with the parasite, as characterized by the transcriptional upregulation of ppara itself and several downstream target genes such as pltp and cpt1. Overall, PPARα did not seem to have any influence on the immune response against G. muris, since PPARα KO animals expressed il-17a and could clear the infection similar to WT controls. In conclusion, this study shows for the first time the importance of IL-17 production in the clearance of a G. muris infection together with an early induction of PPARα. The effect of the latter, however, is still unclear. PMID:24866800

Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in 1-2-month-old highland yaks in Qinghai Province, China.

PubMed

Wang, Geping; Wang, Guanghua; Li, Xiuping; Zhang, Xueyong; Karanis, Gabriele; Jian, Yingna; Ma, Liqing; Karanis, Panagiotis

2018-06-01

Cryptosporidium and Giardia are ubiquitous parasites that infect humans and animals. Few reports are available on the prevalence of these two protozoan parasites in yaks (Bos grunniens). In this study, 344 faecal samples were collected from yaks with diarrhoea in the Chenduo and Nangqian counties of Qinghai Province, China. Cryptosporidium spp. and Giardia duodenalis were detected by light and immunofluorescence microscopy and nested PCR (nPCR). Fifteen samples were positive (4.5%) by Kinyoun staining, 40 (11.6%) samples were positive by immunofluorescence test (IFT), and 39 (11.3%) samples were positive by nPCR for Cryptosporidium spp., Cryptosporidium bovis (11/39, 28.2%) was the most prevalent species, followed by C. ryanae (6/39, 15.4%), C. andersoni (5/39, 12.8%), C. struthionis (5/39, 12.8%), C. parvum (5/39, 12.8%), C. hominis (4/39, 10.3%) and C. canis (3/39, 7.7%). Thirteen out of 344 (3.8%) samples were positive for Giardia by simple microscopy, 20 (5.8%) by IFT and 18 samples (5.2%) yak faecal samples were Giardia positive by nPCR. Two G. duodenalis assemblages (B, E) were detected in this study. Nine positive samples for G. duodenalis assemblage E were from the towns of Xiewu (8/9, 4.9%) and Xiangda (1/9, 1.3%), and nine positive samples (9/9, 8.5%) for G. duodenalis assemblage B were from the town of Zhenqin. This report provides information about infection with Cryptosporidium species and G. duodenalis assemblages in domesticated 1-2-month-old highland yaks living in the Qinghai-Tibet Plateau region of China.

Multilocus sequence analysis of Giardia spp. isolated from patients with diarrhea in Austria.

PubMed

Lee, Mellesia F; Auer, Herbert; Lindo, John F; Walochnik, Julia

2017-02-01

Giardia duodenalis is a protozoan parasite causing intestinal infections in a wide range of mammals. Two distinct assemblages, A and B, infect humans predominantly; however, both are believed to be generally zoonotic. Giardia strains associated with infections in Austria have not been investigated at the molecular level. In this study, 65 human stool samples microscopically positive for Giardia spp. were subjected to DNA isolation and nested PCR targeting fragments of the glutamate dehydrogenase (gdh), triose phosphate isomerase (tpi), and beta-gardin (bg) genes. A total of 52 samples were successfully analyzed using PCR and DNA sequencing. Assemblage B was detected most frequently and accounted for 65.4% (34/52) of infections, while Assemblage A accounted for 34.6% (18/52). There was a high level of genetic diversity among the isolates with 46.2% designated as sub-assemblage BIV (24/52), 25% sub-assemblage AII (13/52), 19.2% sub-assemblage BIII (10/52), and 9.6% sub-assemblage AI (5/52). No mixed infections were detected. The results suggest that the majority of infections were imported and that endemic anthroponotic transmission plays a minor role in Austria.

Human Memory CD4+ T Cell Immune Responses against Giardia lamblia

PubMed Central

Sørnes, Steinar; Peirasmaki, Dimitra; Svärd, Staffan; Langeland, Nina

2015-01-01

The intestinal protozoan parasite Giardia lamblia may cause severe prolonged diarrheal disease or pass unnoticed as an asymptomatic infection. T cells seem to play an important role in the immune response to Giardia infection, and memory responses may last years. Recently, TH17 responses have been found in three animal studies of Giardia infection. The aim of this study was to characterize the human CD4+ T cell responses to Giardia. Peripheral blood mononuclear cells (PBMCs) were obtained from 21 returning travelers with recent or ongoing giardiasis and 12 low-risk healthy controls and stimulated in vitro with Giardia lamblia proteins. Production of tumor necrosis factor alpha (TNF-α), gamma interferon, interleukin-17A (IL-17A), IL-10, and IL-4 was measured in CD4+ effector memory (EM) T cells after 24 h by flow cytometry. After 6 days of culture, activation and proliferation were measured by flow cytometry, while an array of inflammatory cytokine levels in supernatants were measured with multiplex assays. We found the number of IL-17A-producing CD4+ EM T cells, as well as that of cells simultaneously producing both IL-17A and TNF-α, to be significantly elevated in the Giardia-exposed individuals after 24 h of antigen stimulation. In supernatants of PBMCs stimulated with Giardia antigens for 6 days, we found inflammation-associated cytokines, including 1L-17A, as well as CD4+ T cell activation and proliferation, to be significantly elevated in the Giardia-exposed individuals. We conclude that symptomatic Giardia infection in humans induces a CD4+ EM T cell response of which IL-17A production seems to be an important component. PMID:26376930

Giardia co-infection promotes the secretion of antimicrobial peptides beta-defensin 2 and trefoil factor 3 and attenuates attaching and effacing bacteria-induced intestinal disease.

PubMed

Manko, Anna; Motta, Jean-Paul; Cotton, James A; Feener, Troy; Oyeyemi, Ayodele; Vallance, Bruce A; Wallace, John L; Buret, Andre G

2017-01-01

Our understanding of polymicrobial gastrointestinal infections and their effects on host biology remains incompletely understood. Giardia duodenalis is an ubiquitous intestinal protozoan parasite infecting animals and humans. Concomitant infections with Giardia and other gastrointestinal pathogens commonly occur. In countries with poor sanitation, Giardia infection has been associated with decreased incidence of diarrheal disease and fever, and reduced serum inflammatory markers release, via mechanisms that remain obscure. This study analyzed Giardia spp. co-infections with attaching and effacing (A/E) pathogens, and assessed whether and how the presence of Giardia modulates host responses to A/E enteropathogens, and alters intestinal disease outcome. In mice infected with the A/E pathogen Citrobacter rodentium, co-infection with Giardia muris significantly attenuated weight loss, macro- and microscopic signs of colitis, bacterial colonization and translocation, while concurrently enhancing the production and secretion of antimicrobial peptides (AMPs) mouse β-defensin 3 and trefoil factor 3 (TFF3). Co-infection of human intestinal epithelial cells (Caco-2) monolayers with G. duodenalis trophozoites and enteropathogenic Escherichia coli (EPEC) enhanced the production of the AMPs human β-defensin 2 (HBD-2) and TFF3; this effect was inhibited with treatment of G. duodenalis with cysteine protease inhibitors. Collectively, these results suggest that Giardia infections are capable of reducing enteropathogen-induced colitis while increasing production of host AMPs. Additional studies also demonstrated that Giardia was able to directly inhibit the growth of pathogenic bacteria. These results reveal novel mechanisms whereby Giardia may protect against gastrointestinal disease induced by a co-infecting A/E enteropathogen. Our findings shed new light on how microbial-microbial interactions in the gut may protect a host during concomitant infections.

Giardia co-infection promotes the secretion of antimicrobial peptides beta-defensin 2 and trefoil factor 3 and attenuates attaching and effacing bacteria-induced intestinal disease

PubMed Central

Manko, Anna; Motta, Jean-Paul; Cotton, James A.; Feener, Troy; Oyeyemi, Ayodele; Vallance, Bruce A.; Wallace, John L.

2017-01-01

Our understanding of polymicrobial gastrointestinal infections and their effects on host biology remains incompletely understood. Giardia duodenalis is an ubiquitous intestinal protozoan parasite infecting animals and humans. Concomitant infections with Giardia and other gastrointestinal pathogens commonly occur. In countries with poor sanitation, Giardia infection has been associated with decreased incidence of diarrheal disease and fever, and reduced serum inflammatory markers release, via mechanisms that remain obscure. This study analyzed Giardia spp. co-infections with attaching and effacing (A/E) pathogens, and assessed whether and how the presence of Giardia modulates host responses to A/E enteropathogens, and alters intestinal disease outcome. In mice infected with the A/E pathogen Citrobacter rodentium, co-infection with Giardia muris significantly attenuated weight loss, macro- and microscopic signs of colitis, bacterial colonization and translocation, while concurrently enhancing the production and secretion of antimicrobial peptides (AMPs) mouse β-defensin 3 and trefoil factor 3 (TFF3). Co-infection of human intestinal epithelial cells (Caco-2) monolayers with G. duodenalis trophozoites and enteropathogenic Escherichia coli (EPEC) enhanced the production of the AMPs human β-defensin 2 (HBD-2) and TFF3; this effect was inhibited with treatment of G. duodenalis with cysteine protease inhibitors. Collectively, these results suggest that Giardia infections are capable of reducing enteropathogen-induced colitis while increasing production of host AMPs. Additional studies also demonstrated that Giardia was able to directly inhibit the growth of pathogenic bacteria. These results reveal novel mechanisms whereby Giardia may protect against gastrointestinal disease induced by a co-infecting A/E enteropathogen. Our findings shed new light on how microbial-microbial interactions in the gut may protect a host during concomitant infections. PMID:28622393

Multicenter Evaluation of BD Max Enteric Parasite Real-Time PCR Assay for Detection of Giardia duodenalis, Cryptosporidium hominis, Cryptosporidium parvum, and Entamoeba histolytica

PubMed Central

Relich, R. F.; Doyle, L.; Espina, N.; Fuller, D.; Karchmer, T.; Lainesse, A.; Mortensen, J. E.; Pancholi, P.; Veros, W.; Harrington, S. M.

2016-01-01

Common causes of chronic diarrhea among travelers worldwide include protozoan parasites. The majority of parasitic infections are caused by Giardia duodenalis, Entamoeba histolytica, Cryptosporidium parvum, and Cryptosporidium hominis. Similarly, these species cause the majority of parasitic diarrhea acquired in the United States. Detection of parasites by gold standard microscopic methods is time-consuming and requires considerable expertise; enzyme immunoassays and direct fluorescent-antibody (DFA) stains have lowered hands-on time for testing, but improvements in sensitivity and technical time may be possible with a PCR assay. We performed a clinical evaluation of a multiplex PCR panel, the enteric parasite panel (EPP), for the detection of these common parasites using the BD Max instrument, which performs automated extraction and amplification. A total of 2,495 compliant specimens were enrolled, including 2,104 (84%) specimens collected prospectively and 391 (16%) specimens collected retrospectively. Approximately equal numbers were received in 10% formalin (1,273 specimens) and unpreserved (1,222 specimens). The results from the EPP were compared to those from alternate PCR and bidirectional sequencing (APCR), as well as DFA (G. duodenalis and C. parvum or C. hominis) or trichrome stain (E. histolytica). The sensitivity and specificity for prospective and retrospective specimens combined were 98.2% and 99.5% for G. duodenalis, 95.5% and 99.6 for C. parvum or C. hominis, and 100% and 100% for E. histolytica, respectively. The performance of the FDA-approved BD Max EPP compared well to the reference methods and may be an appropriate substitute for microscopic examination or immunoassays. PMID:27535690

Parasitological surveillance in a rat (Rattus norvegicus) colony in São Paulo Zoo animal house

PubMed

Chagas, Carolina Romeiro Fernandes; Gonzalez, Irys Hany Lima; Favoretto, Samantha Mesquita; Ramos, Patrícia Locosque

Rattus norvegicus (Mammalia: Rodentia) is a widespread and synanthropic rodent, broadly used in medical experiments. It can also be used for feeding captive animals in zoos. Parasitological surveys are important to guarantee the health of both the animals and the staff responsible for their management. The aim of this study was to identify intestinal parasites of Rattus norvegicus offered as food to captive animals from São Paulo Zoo, and demonstrate the importance of sanitary hurdling, disease control and biosecurity. The identified protozoan parasites were Eimeria sp., Entamoeba sp., Spironucleus sp., Giardia sp., Tritrichomonas sp., Chilomastix sp., unidentified cysts and non-sporulated coccidians oocysts (Isospora/Eimeria). The following helminths were found: Syphacia muris, Rodentolepis nana and Aspiculuris tetraptera.

O2-Dependent Efficacy of Novel Piperidine- and Piperazine-Based Chalcones against the Human Parasite Giardia intestinalis

PubMed Central

Bahadur, Vijay; Mastronicola, Daniela; Tiwari, Hemandra Kumar; Kumar, Yogesh; Falabella, Micol; Pucillo, Leopoldo Paolo; Sarti, Paolo

2014-01-01

Giardia intestinalis is the most frequent protozoan agent of intestinal diseases worldwide. Though commonly regarded as an anaerobic pathogen, it preferentially colonizes the fairly oxygen-rich mucosa of the proximal small intestine. Therefore, when testing new potential antigiardial drugs, O2 should be taken into account, since it also reduces the efficacy of metronidazole, the gold standard drug against giardiasis. In this study, 46 novel chalcones were synthesized by microwave-assisted Claisen-Schmidt condensation, purified, characterized by high-resolution mass spectrometry, 1H and 13C nuclear magnetic resonance, and infrared spectroscopy, and tested for their toxicity against G. intestinalis under standard anaerobic conditions. As a novel approach, compounds showing antigiardial activity under anaerobiosis were also assayed under microaerobic conditions, and their selectivity against parasitic cells was assessed in a counterscreen on human epithelial colorectal adenocarcinoma cells. Among the tested compounds, three [30(a), 31(e), and 33] were more effective in the presence of O2 than under anaerobic conditions and killed the parasite 2 to 4 times more efficiently than metronidazole under anaerobiosis. Two of them [30(a) and 31(e)] proved to be selective against parasitic cells, thus representing potential candidates for the design of novel antigiardial drugs. This study highlights the importance of testing new potential antigiardial agents not only under anaerobic conditions but also at low, more physiological O2 concentrations. PMID:24217695

Checking the detail in retail: Occurrence of Cryptosporidium and Giardia on vegetables sold across different counters in Chandigarh, India.

PubMed

Utaaker, Kjersti Selstad; Kumar, Anil; Joshi, Himanshu; Chaudhary, Suman; Robertson, Lucy J

2017-12-18

Fresh produce has been recognized as a vehicle of infection for protozoan parasites, particularly Cryptosporidium, and, to a lesser extent, Giardia. For both parasites, outbreaks associated with fresh produce have been documented. Although documented outbreaks tend to be from industrialized countries, contamination of fresh produce with these parasites is a global issue. In developing countries, infections with these parasites are often endemic in the community, and basic infrastructure and hygiene measures may be inadequate, thus the likelihood of contamination of fresh produce with these parasites may be higher. Realization of the importance of this transmission route comes against a backdrop of raw salads and more Western culinary habits gaining a foothold, and fresh produce being encouraged as part of the diet due to their associated health benefits. However, if consumption of uncooked fresh produce is going to increase its market sector in India, it is important that it is safe. In this study, various types of fresh produce obtained from three types of vendors in Chandigarh, a major city in Northern India, were analyzed for contamination with Cryptosporidium oocysts and Giardia cysts using a method that has been previously validated in inter-laboratory spiking experiments. A total of 284 samples of different fresh produce items were analyzed, obtained from the different retailers situated in different societal layers of the city. The overall prevalence of contamination of fresh produce with these parasites was just under 11%, with 6% of the vegetables contaminated with Cryptosporidium oocysts, and 5% with Giardia cysts. Contaminated vegetables included turnip, cabbage, carrot, chili, coriander, cucumber, radishes, and tomatoes. Molecular analyses identified contamination with Cryptosporidium parvum and Giardia duodenalis of Assemblage A and Assemblage D, indicating that contamination from animals may be of relevance. Although the prevalence of contamination is similar to those reported in previous studies, the levels of contamination on some items of fresh produce were relatively high. Although the different socioeconomic areas of Chandigarh from which the samples were obtained was not associated with likelihood of contamination, fresh produce from supermarkets had heavier contamination with Cryptosporidium oocysts than fresh produce purchased through other sales outlets. The results are discussed in relation to the fresh produce chain and sales models in Chandigarh, both in terms of where contamination may occur and the potential importance of fresh produce as a transmission vehicle. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetic diversity within the morphological species Giardia intestinalis and its relationship to host origin.

PubMed

Monis, Paul T; Andrews, Ross H; Mayrhofer, Graham; Ey, Peter L

2003-05-01

A genetic analysis of Giardia intestinalis, a parasitic protozoan species that is ubiquitous in mammals worldwide, was undertaken using organisms derived from a variety of mammalian hosts in different geographical locations. The test panel of 53 Giardia isolates comprised 48 samples of G. intestinalis, including representatives of all known genetic subgroups, plus an isolate of G. ardeae and four isolates of G. muris. The isolates were compared by allozymic analysis of electrophoretic data obtained for 21 cytosolic enzymes, representing 23 gene loci. Neighbour Joining analysis of the allelic profiles supported the monophyly of G. intestinalis but showed that the species encompasses a rich population substructure. Seven major clusters were evident within G. intestinalis, corresponding to lineages designated previously as genetic assemblages A-G. Some genotypes, e.g. those defining assemblage A, are found in divergent host species and may be zoonotic. However other genotypes, e.g. those defining assemblages C-G, appear to be confined to particular hosts or host groups. The findings reinforce other evidence that G. intestinalis, which was defined on the basis of morphological criteria only, is a species complex.

Burden of major diarrheagenic protozoan parasitic co-infection among amoebic dysentery cases from North East India: a case report.

PubMed

Nath, Joyobrato; Hussain, Gulzar; Singha, Baby; Paul, Jaishree; Ghosh, Sankar Kumar

2015-09-01

Intestinal diarrheagenic polyparasitic infections are among the major public health concerns in developing countries. Here we examined stool specimens by microscopy, DNA dot blot and polymerase chain reaction (PCR) to evaluate the co-infection of four principal protozoans among amoebic dysentery cases from Northeast Indian population. The multiplex PCR confirmed Entamoeba histolytica (8.1%), Entamoeba dispar (4.8%) and mixed infection of both the parasites (3.4%) in 68 of 356 stool specimens that were positive in microscopy and/or HMe probe based DNA dot blot screening. The prevailing parasite that co-exists with E. histolytica was Giardia duodenalis (34.1%), followed by Enterocytozoon bieneusi (22.0%), Cryptosporidium parvum (14.6%) and Cyclospora cayetanensis (7.3%, P = 0.017). Symptomatic participants (odds ratio (OR) = 4.07; 95% confidence interval (CI) = 1.06, 15.68; P = 0.041), monsoon season (OR = 7.47; 95% CI = 1.40, 39.84; P = 0.046) and participants with family history of parasitic infection (OR = 4.50; 95% CI = 1.16, 17.51; P = 0.030) have significant association with overall co-infection rate. According to molecular consensus, comprehensive microscopy yielded 3.4% (12/356) false-negative and 7.6% (27/356) false-positive outcome, suggesting an improved broad-spectrum PCR-based diagnostic is required to scale down the poor sensitivity and specificity as well as implementation of integrated control strategy.

Activities of several benzimidazoles and tubulin inhibitors against Giardia spp. in vitro.

PubMed Central

Morgan, U M; Reynoldson, J A; Thompson, R C

1993-01-01

Previous studies in our laboratory have shown that albendazole is effective against Giardia spp. in vitro and in vivo, prompting an investigation of the effects of several related benzimidazoles (BZs) on the viability of this protozoan parasite. A range of BZs was tested, and their effects were compared with those of a number of microtubule inhibitors. The effects produced by the two types of drugs were markedly similar, namely, trophozoite detachment and distortion of morphology and general structure, indicating a potential antimicrotubule mode of action for BZs. Mebendazole, albendazole, and fenbendazole proved to be among the most effective BZs tested, exhibiting apparent irreversibility. Nocodazole, oxfendazole, and albendazole sulfoxide, among others, produced transient inhibitions only. Further studies are required to evaluate all available BZs and other antigiardial agents to ensure the development of the most effective and safest antigiardial agent possible. PMID:8452365

Fine-Scale Spatial Heterogeneity in the Distribution of Waterborne Protozoa in a Drinking Water Reservoir.

PubMed

Burnet, Jean-Baptiste; Ogorzaly, Leslie; Penny, Christian; Cauchie, Henry-Michel

2015-09-23

The occurrence of faecal pathogens in drinking water resources constitutes a threat to the supply of safe drinking water, even in industrialized nations. To efficiently assess and monitor the risk posed by these pathogens, sampling deserves careful design, based on preliminary knowledge on their distribution dynamics in water. For the protozoan pathogens Cryptosporidium and Giardia, only little is known about their spatial distribution within drinking water supplies, especially at fine scale. Two-dimensional distribution maps were generated by sampling cross-sections at meter resolution in two different zones of a drinking water reservoir. Samples were analysed for protozoan pathogens as well as for E. coli, turbidity and physico-chemical parameters. Parasites displayed heterogeneous distribution patterns, as reflected by significant (oo)cyst density gradients along reservoir depth. Spatial correlations between parasites and E. coli were observed near the reservoir inlet but were absent in the downstream lacustrine zone. Measurements of surface and subsurface flow velocities suggest a role of local hydrodynamics on these spatial patterns. This fine-scale spatial study emphasizes the importance of sampling design (site, depth and position on the reservoir) for the acquisition of representative parasite data and for optimization of microbial risk assessment and monitoring. Such spatial information should prove useful to the modelling of pathogen transport dynamics in drinking water supplies.

Molecular Analysis of the Enteric Protozoa Associated with Acute Diarrhea in Hospitalized Children.

PubMed

Boughattas, Sonia; Behnke, Jerzy M; Al-Ansari, Khalid; Sharma, Aarti; Abu-Alainin, Wafa; Al-Thani, Asma; Abu-Madi, Marawan A

2017-01-01

Pediatric diarrhea is a common cause of death among children under 5 years of age. In the current study, we investigated the frequency of intestinal parasites among 580 pediatric patients with chronic diarrhea. Parasitic protozoa (all species combined) were detected by molecular tools in 22.9% of the children and the most common parasite was Cryptosporidium spp. (15.1%). Blastocystis hominis was detected in 4.7%, Dientamoeba fragilis in 4%, Giardia duodenalis in 1.7%, and Entamoeba histolytica in 0.17%. Protozoan infections were observed among all regional groups, but prevalence was highest among Qatari subjects and during the winter season. Typing of Cryptosporidium spp. revealed a predominance of Cryptosporidium parvum in 92% of cases with mostly the IIdA20G1 subtype. Subtypes IIdA19G2, IIdA18G2, IIdA18G1, IIdA17G1, IIdA16G1, and IIdA14G1 were also detected. For Cryptosporidium hominis , IbA10G2 and IbA9G3 subtypes were identified. This study provides supplementary information for implementing prevention and control strategies to reduce the burden of these pediatric protozoan infections. Further analyses are required to better understand the local epidemiology and transmission of Cryptosporidium spp. in Qatar.

Comparison of the levels of intra-specific genetic variation within Giardia muris and Giardia intestinalis.

PubMed

Andrews, R H; Monis, P T; Ey, P L; Mayrhofer, G

1998-08-01

The extent of intra-specific genetic variation between isolates of Giardia muris was assessed by allozyme electrophoresis. Additionally, the levels of allozymic variation detected within G. muris were compared with those observed between members of the two major assemblages of the morphologically distinct species Giardia intestinalis. Four isolates of G. muris were analysed. Three (Ad-120, -150, -151) were isolated from mice in Australia, while the fourth (R-T) was isolated from a golden hamster in North America. The 11 isolates of G. intestinalis (Ad-1, -12, -2, -62, representing genetic Groups I and II of Assemblage A and BAH-12, BRIS/87/HEPU/694, Ad-19, -22, -28, -45, -52, representing genetic Groups III and IV of Assemblage B) were from humans in Australia. Intra-specific genetic variation was detected between G. muris isolates at four of the 23 enzyme loci examined. Similar levels of variation were found within the genetic groups that comprise Assemblages A and B of G. intestinalis. These levels of intra-specific variation are similar to those observed within other morphologically-distinct species of protozoan parasites. We suggest that the magnitude of the genetic differences detected within G. muris provides an indication of the range of genetic variation within other species of Giardia and that this can be used as a model to delineate morphologically similar but genetically distinct (cryptic) species within this genus.

Curcumin alters the cytoskeleton and microtubule organization on trophozoites of Giardia lamblia.

PubMed

Gutiérrez-Gutiérrez, Filiberto; Palomo-Ligas, Lissethe; Hernández-Hernández, José Manuel; Pérez-Rangel, Armando; Aguayo-Ortiz, Rodrigo; Hernández-Campos, Alicia; Castillo, Rafael; González-Pozos, Sirenia; Cortés-Zárate, Rafael; Ramírez-Herrera, Mario Alberto; Mendoza-Magaña, María Luisa; Castillo-Romero, Araceli

2017-08-01

Giardia lamblia is a worldwide protozoan responsible for a significant number of intestinal infections. There are several drugs for the treatment of giardiasis, but they often cause side effects. Curcumin, a component of turmeric, has antigiardial activity; however, the molecular target and mechanism of antiproliferative activity are not clear. The effects of curcumin on cellular microtubules have been widely investigated. Since tubulin is the most abundant protein in the cytoskeleton of Giardia, to elucidate whether curcumin has activity against the microtubules of this parasite, we treated trophozoites with curcumin and the cells were analyzed by scanning electron microscopy and confocal microscopy. Curcumin inhibited Giardia proliferation and adhesion in a time-concentration-dependent mode. The higher inhibitory concentrations of curcumin (3 and 15μM) disrupted the cytoskeletal structures of trophozoites; the damage was evident on the ventral disk, flagella and in the caudal region, also the membrane was affected. The immunofluorescence images showed altered distribution of tubulin staining on ventral disk and flagella. Additionally, we found that curcumin caused a clear reduction of tubulin expression. By docking analysis and molecular dynamics we showed that curcumin has a high probability to bind at the interface of the tubulin dimer close to the vinblastine binding site. All the data presented indicate that curcumin may inhibit Giardia proliferation by perturbing microtubules. Copyright © 2017. Published by Elsevier B.V.

Surveillance Systems for Waterborne Protozoa: Beyond Method 1623

EPA Science Inventory

1. Brief introduction to waterborne Cryptosporidium and Giardia Historical perspective on detecting Cryptosporidium and Giardia Current detection methodologies 2. US EPA’s waterborne protozoan research program Building a “Protoz...

Molecular identification of zoonotic and livestock-specific Giardia-species in faecal samples of calves in Southern Germany.

PubMed

Gillhuber, Julia; Pallant, Louise; Ash, Amanda; Thompson, R C Andrew; Pfister, Kurt; Scheuerle, Miriam C

2013-12-10

Giardia-infection in cattle is often subclinical or asymptomatic, but it can also cause diarrhoea. The livestock-specific species Giardia bovis is the most frequently observed in cattle, however, the two zoonotic species Giardia duodenalis and Giardia enterica have also been found. Therefore calves are thought to be of public health significance. The aim of this study was to obtain current data about the frequency of the different Giardia-species in calves in Southern Germany. Faecal samples of calves (diarrhoeic and healthy) in Southern Germany, diagnosed Giardia-positive by microscopy, were characterised by multi-locus PCR and sequencing.Of 152 microscopically Giardia-positive samples 110 (72.4%) were positive by PCR and successfully sequenced. G. bovis (Assemblage E) was detected in 101/110 (91.8%) PCR-positive samples, whilst G. duodenalis (Assemblage A) was detected in 8/110 (7.3%) samples and a mixed infection with G. duodenalis and G. bovis (Assemblage A+E) was identified in 1/110 (0.9%) samples. The sub-genotypes A1, E2 and E3 were identified with the β-giardin and the glutamate dehydrogenase genes. In the majority of diarrhoeic faecal samples a co-infection with Cryptosporidium spp. or Eimeria spp. was present, however, there were some in which G. bovis was the only protozoan pathogen found. The results suggest that there is potentially a risk for animal handlers as calves in Southern Germany are, at a low percentage, infected with the zoonotic species G. duodenalis. In addition, it was found that G. bovis was the only pathogen identified in some samples of diarrhoeic calves, indicating that this parasite may be a contributing factor to diarrhoea in calves.

First survey of Cryptosporidium, Giardia and Enterocytozoon in diarrhoeic children from Wuhan, China.

PubMed

Wang, Tao; Fan, Yingying; Koehler, Anson V; Ma, Guangxu; Li, Tao; Hu, Min; Gasser, Robin B

2017-07-01

Intestinal protozoan pathogens cause significant diarrhoeal diseases in children. However, to date, there has been limited genetic study of the intestinal pathogens Cryptosporidium, Giardia and Enterocytozoon in humans in China, with the exception of research in a small number of cities/provinces. In the present study, PCR-based tools were used to detect and characterise these protistan parasites from 500 children with a history of diarrhoea in Wuhan and environs, Hubei province, China. Genomic DNAs from faecal samples were screened for the particular protists by PCR utilising regions in the small subunit (SSU) of the nuclear ribosomal RNA, the 60kDa glycoprotein (gp60), the internal transcribed spacer of nuclear ribosomal DNA (ITS) and/or the triose phosphate isomerase (tpi) genes as markers. Cryptosporidium meleagridis subtype IIIb (10/500, 2.0%), Giardia duodenalis assemblage A (7/500, 1.4%) and Enterocytozoon bieneusi genotype D (1/500, 0.2%) were identified in small percentages of the 500 samples. No significant gender- or age-associated differences in the prevalence of Cryptosporidium and Giardia infections were found. Future studies might focus on the occurrence of these protists in children as well as animals, with an emphasis on Cryptosporidium meleagridis in pets and agriculturally important birds, in different parts of Hubei province. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular Epidemiology of Giardia, Blastocystis and Cryptosporidium among Indigenous Children from the Colombian Amazon Basin.

PubMed

Sánchez, Angie; Munoz, Marina; Gómez, Natalia; Tabares, Juan; Segura, Laura; Salazar, Ángela; Restrepo, Cristian; Ruíz, Miguel; Reyes, Patricia; Qian, Yuchen; Xiao, Lihua; López, Myriam C; Ramírez, Juan D

2017-01-01

The incidence and prevalence of intestinal parasites in children is most likely due to lack of natural or acquired resistance and differences in behavior and habits closely related to environmental and socioeconomic determinants. The most important protozoa that parasitize humans are Giardia, Entamoeba, Blastocystis , and Cryptosporidium . These parasites present wide intraspecific genetic diversity and subsequently classified into assemblages and subtypes. The Amazon basin is the largest in the world and is the fifth freshwater reserve on the planet. Contradictorily, people living in these areas (Indigenous populations) have poor quality of life, which favors the infection of diseases of fecal-oral transmission. The aim of this work was to unravel the molecular epidemiology of Giardia, Blastocystis and Cryptosporidium across four communities (Puerto Nariño, San Juan del Soco, Villa Andrea and Nuevo Paraíso). We obtained 284 fecal samples from children under 15 years old that were analyzed by direct microscopy (261 samples) and Real Time PCR (qPCR) (284 samples). The positive samples for these protozoa were further characterized by several molecular markers to depict assemblages and subtypes. We observed a frequency of Giardia infection by microscopy of 23.7% (62 samples) and by qPCR of 64.8% (184 samples); for Blastocystis by microscopy of 35.2% (92 samples) and by qPCR of 88.7% (252 samples) and for Cryptosporidium only 1.9% (5 samples) were positive by microscopy and qPCR 1.8% (5 samples). Regarding the Giardia assemblages, using the glutamate dehydrogenase ( gdh) marker we observed AI, BIII and BIV assemblages and when using triose phosphate isomerase ( tpi ) we observed assemblages AI, AII, BIII and BIV. In contrast, Blastocystis STs detected were 1, 2, 3, 4, and 6. Lastly, the species C. viatorum, C. hominis (with the subtypes IdA19 and IaA12R8) and C. parvum (with the subtype IIcA5G3c) were identified. We observed a high profile of zoonotic transmission regarding the Giardia assemblages and Blastocystis STs/alleles. Also, we highlight the elevated frequency of infection by these two protozoans suggesting an active transmission in the area. Our findings reinforces the need to deploy better epidemiological surveillance systems for enteric pathogens in the area.

Criteria For Evaluation of Proposed Protozoan Detection Methods

EPA Science Inventory

Currently, the only EPA approved method for detection and quantitation of protozoan cysts and oöcysts in source and drinking water, is the “ICR Protozoan Method for Detecting Giardia Cysts and Cryptosporidium Oöcysts in Water by a Fluorescent Antibody Procedure (ICR Microbial La...

Giardia duodenalis assemblages and Entamoeba species infecting non-human primates in an Italian zoological garden: zoonotic potential and management traits

PubMed Central

2011-01-01

Background Giardia duodenalis and Entamoeba spp. are among the most common intestinal human protozoan parasites worldwide and they are frequently reported in captive non-human primates (NHP). From a public health point of view, infected animals in zoos constitute a risk for animal caretakers and visitors. In this study we carried out the molecular identification of G. duodenalis and Entamoeba spp. from nine species of primates housed in the zoological garden of Rome, to better ascertain their occurrence and zoonotic potential. Results G. duodenalis was found only in Lemur catta (47.0%). Entamoeba spp. were detected in all species studied, with the exception of Eulemur macaco and Varecia rubra. The number of positive pools ranged from 5.9% in L. catta to 81.2% in Mandrillus sphinx; in Pan troglodytes the observed prevalence was 53.6%. A mixed Entamoeba-Giardia infection was recorded only in one sample of L. catta. All G. duodenalis isolates belonged to the zoonotic assemblage B, sub assemblage BIV. Three Entamoeba species were identified: E. hartmanni, E. coli and E. dispar. Conclusions Our results highlight the importance of regularly testing animals kept in zoos for the diagnosis of zoonotic parasites, in order to evaluate their pathogenic role in the housed animals and the zoonotic risk linked to their presence. A quick detection of the arrival of pathogens into the enclosures could also be a prerequisite to limit their spread into the structure via the introduction of specific control strategies. The need for molecular identification of some parasite species/genotype in order to better define the zoonotic risk is also highlighted. PMID:21988762

Jejunal brush border microvillous alterations in Giardia muris-infected mice: role of T lymphocytes and interleukin-6.

PubMed

Scott, K G; Logan, M R; Klammer, G M; Teoh, D A; Buret, A G

2000-06-01

Intestinal colonization with the protozoan Giardia causes diffuse brush border microvillous alterations and disaccharidase deficiencies, which in turn are responsible for intestinal malabsorption and maldigestion. The role of T cells and/or cytokines in the pathogenesis of Giardia-induced microvillous injury remains unclear. The aim of this study was to assess the role of T cells and interleukin-6 (IL-6) in the brush border pathophysiology of acute murine giardiasis in vivo. Athymic nude (nu(-)/nu(-)) CD-1 mice and isogenic immunocompetent (nu(+)/nu(+)) CD-1 mice (4 weeks old) received an axenic Giardia muris trophozoite inoculum or vehicle (control) via orogastric gavage. Weight gain and food intake were assessed daily. On day 6, segments of jejunum were assessed for parasite load, brush border ultrastructure, IL-6 content, maltase and sucrase activities, villus-crypt architecture, and intraepithelial lymphocyte (IEL) infiltration. Despite similar parasitic loads on day 6, infected immunocompetent animals, but not infected nude mice, showed a diffuse loss of brush border microvillous surface area, which was correlated with a significant reduction in maltase and sucrase activities and a decrease in jejunal IL-6 concentration. In both athymic control and infected mice, jejunal brush border surface area and disaccharidases were high, but levels of tissue IL-6 were low and comparable to the concentration measured in immunocompetent infected animals. In both immunocompetent and nude mice, infection caused a small but significant increase in the numbers of IELs. These findings suggest that the enterocyte brush border injury and malfunction seen in giardiasis is, at least in part, mediated by thymus-derived T lymphocytes and that suppressed jejunal IL-6 does not necessarily accompany microvillous shortening.

Identification of a nicotinamide/nicotinate mononucleotide adenylyltransferase in Giardia lamblia (GlNMNAT).

PubMed

Forero-Baena, Nicolás; Sánchez-Lancheros, Diana; Buitrago, July Constanza; Bustos, Victor; Ramírez-Hernández, María Helena

2015-01-01

Giardia lamblia is an intestinal protozoan parasite that causes giardiasis, a disease of high prevalence in Latin America, Asia and Africa. Giardiasis leads to poor absorption of nutrients, severe electrolyte loss and growth retardation. In addition to its clinical importance, this parasite is of special biological interest due to its basal evolutionary position and simplified metabolism, which has not been studied thoroughly. One of the most important and conserved metabolic pathways is the biosynthesis of nicotinamide adenine dinucleotide (NAD). This molecule is widely known as a coenzyme in multiple redox reactions and as a substrate in cellular processes such as synthesis of Ca 2+ mobilizing agents, DNA repair and gene expression regulation. There are two pathways for NAD biosynthesis, which converge at the step catalyzed by nicotinamide/nicotinate mononucleotide adenylyltransferase (NMNAT, EC 2.7.7.1/18). Using bioinformatics tools, we found two NMNAT sequences in Giardia lamblia ( glnmnat-a and glnmnat-b ). We first verified the identity of the sequences in silico . Subsequently, glnmnat-a was cloned into an expression vector. The recombinant protein (His-GlNMNAT) was purified by nickel-affinity binding and was used in direct in vitro enzyme assays assessed by C18-HPLC, verifying adenylyltransferase activity with both nicotinamide (NMN) and nicotinic acid (NAMN) mononucleotides. Optimal reaction pH and temperature were 7.3 and 26 °C. Michaelis-Menten kinetics were observed for NMN and ATP, but saturation was not accomplished with NAMN, implying low affinity yet detectable activity with this substrate. Double-reciprocal plots showed no cooperativity for this enzyme. This represents an advance in the study of NAD metabolism in Giardia spp.

Chitin synthetase in encysting Giardia lamblia and Entamoeba invadens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Das, S.; Gillin, F.D.

1987-05-01

Giardia lamblia (Gl) and Entamoeba invadens (Ei) are protozoan parasites with two morphologic stages in their life cycles. Motile trophozoites colonize the intestine of humans and reptiles respectively. Water resistant cysts, which can survive outside the host, transmit infection. In vitro cyst formation of Ei from trophozoites has been reported, and the authors have recently induced in vitro encystation of Gl. Although the cyst walls of both parasites contain chitin, it synthesis by encysting trophozoites has not been reported. The authors now show that encystation conditions greatly increase chitin synthetase (CS) specific activity (incorporation of /sup 3/H GlcNAc from UDP-GlcNAcmore » into TCA-or alcohol-precipitable material). Extracts of encysting Gl incorporated 3.6 nmol/mg protein in 5 hr compared to < 0.005 in controls. Extracts of encysting Fi incorporated 4.8 n mol/mg protein, compared to 1.7 in the control. CS activity of both parasites requires preformed chitin. The Gl enzyme requires a reducing agent, is inhibited by digitonin and the CS inhibitors, polyoxin D and Nikkomycin, but not by tunicamycin. The product is digested by chitinase. Ei enzyme does not require a reducing agent and is stimulated by 1 mg/ml digitonin, but inhibited by higher concentrations. These studies demonstrate CS enzymes which may play important roles in encystation of Gl and Ei.« less

Parasitic contamination of fresh vegetables sold at central markets in Khartoum state, Sudan.

PubMed

Mohamed, Mona Ali; Siddig, Emmanuel Edwar; Elaagip, Arwa Hassan; Edris, Ali Mahmoud Mohammed; Nasr, Awad Ahmed

2016-03-11

Fresh vegetables are considered as vital nutrients of a healthy diet as they supply the body with essential supplements. The consumption of raw vegetables is the main way for transmission of intestinal parasitic organisms. This study was aimed at detecting the parasitic contamination in fresh vegetables sold in two central open-aired markets in Khartoum state, Sudan. In this prospective cross-sectional study, a total of 260 fresh vegetable samples and 50 water samples used to sprinkle vegetable(s) were collected from two central open-aired markets (namely; Elshaabi and Central markets) during November 2011 to May 2012. The samples were microscopically examined for detection of parasitic life forms using standardized parasitological techniques for protozoans and helminthes worms. Of the 260 fresh vegetable samples, 35 (13.5 %) were microscopically positive for intestinal parasites whereas 7/50 (14 %) of water samples used to sprinkle vegetable(s) were found positives. Remarkably, high level of contamination in fresh vegetable samples was recorded in lettuce (Lactuca sativa) 36.4 % (4/11) while cayenne pepper (Capsicum annuum) and cucumber (Cucumis sativus) were not contaminated. The identified protozoans and helminthes were Entamoeba histolytica/dispar, Entamoeba coli, Giardia lamblia, Ascaris lumbricoides, Strongyloides stercoralis, T. trichiura and hookworms. The most predominant parasite encountered was E. histolytica/dispar (42.9 %) whereas both T. trichiura and A. lumbricoides (2.9 %) were the least detected parasites. None of the fresh vegetables had single parasitic contamination. The highest percentages found in water samples used to sprinkle vegetable(s) was for Strongyloides larvae 60 % (3/5). It is worth-mentioned that the rate of contamination in Elshaabi market was higher compared with Central market. However, there was no significant correlation between the type of vegetables and existence of parasites in both markets and a high significant relationship was observed between the type of parasite and total prevalence in fresh vegetables (p = 0.000). The study has identified a moderate rate of fresh vegetables contaminated with protozoan and helminthes. Contaminated fresh vegetables in central markets of Khartoum state may play a significant role in transmission of intestinal parasitic infections to humans, and the water used by greengrocers to sprinkle vegetable(s) can be implicated in vegetable contamination.

Application of a Multiplex Quantitative PCR to Assess Prevalence and Intensity Of Intestinal Parasite Infections in a Controlled Clinical Trial

PubMed Central

Llewellyn, Stacey; Inpankaew, Tawin; Nery, Susana Vaz; Gray, Darren J.; Verweij, Jaco J.; Clements, Archie C. A.; Gomes, Santina J.; Traub, Rebecca; McCarthy, James S.

2016-01-01

Background Accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. As morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. The current study aimed to evaluate two multiplex PCR assays to determine prevalence and intensity of intestinal parasite infections, and compare them to standard microscopy. Methodology/Principal Findings Faecal samples were collected from a total of 680 people, originating from rural communities in Timor-Leste (467 samples) and Cambodia (213 samples). DNA was extracted from stool samples and subject to two multiplex real-time PCR reactions the first targeting: Necator americanus, Ancylostoma spp., Ascaris spp., and Trichuris trichiura; and the second Entamoeba histolytica, Cryptosporidium spp., Giardia. duodenalis, and Strongyloides stercoralis. Samples were also subject to sodium nitrate flotation for identification and quantification of STH eggs, and zinc sulphate centrifugal flotation for detection of protozoan parasites. Higher parasite prevalence was detected by multiplex PCR (hookworms 2.9 times higher, Ascaris 1.2, Giardia 1.6, along with superior polyparasitism detection with this effect magnified as the number of parasites present increased (one: 40.2% vs. 38.1%, two: 30.9% vs. 12.9%, three: 7.6% vs. 0.4%, four: 0.4% vs. 0%). Although, all STH positive samples were low intensity infections by microscopy as defined by WHO guidelines the DNA-load detected by multiplex PCR suggested higher intensity infections. Conclusions/Significance Multiplex PCR, in addition to superior sensitivity, enabled more accurate determination of infection intensity for Ascaris, hookworms and Giardia compared to microscopy, especially in samples exhibiting polyparasitism. The superior performance of multiplex PCR to detect polyparasitism and more accurately determine infection intensity suggests that it is a more appropriate technique for use in epidemiologic studies and for monitoring large-scale intervention trials. PMID:26820626

Giardia muris infection in mice is associated with a protective interleukin 17A response and induction of peroxisome proliferator-activated receptor alpha.

PubMed

Dreesen, Leentje; De Bosscher, Karolien; Grit, Grietje; Staels, Bart; Lubberts, Erik; Bauge, Eric; Geldhof, Peter

2014-08-01

The protozoan parasite Giardia duodenalis (Giardia lamblia) is one of the most commonly found intestinal pathogens in mammals, including humans. In the current study, a Giardia muris-mouse model was used to analyze cytokine transcription patterns and histological changes in intestinal tissue at different time points during infection in C57BL/6 mice. Since earlier work revealed the upregulation of peroxisome proliferator-activated receptors (PPARs) in Giardia-infected calves, a second aim was to investigate the potential activation of PPARs in the intestines of infected mice. The most important observation in all mice was a strong upregulation of il17a starting around 1 week postinfection. The significance of interleukin 17A (IL-17A) in orchestrating a protective immune response was further demonstrated in an infection trial or experiment using IL-17 receptor A (IL-17RA) knockout (KO) mice: whereas in wild-type (WT) mice, cyst secretion dropped significantly after 3 weeks of infection, the IL-17RA KO mice were unable to clear the infection. Analysis of the intestinal response further indicated peroxisome proliferator-activated receptor alpha (PPARα) induction soon after the initial contact with the parasite, as characterized by the transcriptional upregulation of ppara itself and several downstream target genes such as pltp and cpt1. Overall, PPARα did not seem to have any influence on the immune response against G. muris, since PPARα KO animals expressed il-17a and could clear the infection similar to WT controls. In conclusion, this study shows for the first time the importance of IL-17 production in the clearance of a G. muris infection together with an early induction of PPARα. The effect of the latter, however, is still unclear. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Molecular Epidemiology of Cryptosporidium spp. and Giardia spp. in Mussels (Mytilus californianus) and California Sea Lions (Zalophus californianus) from Central California

PubMed Central

Adell, A. D.; Shapiro, K.; Melli, A.; Conrad, P. A.

2014-01-01

Cryptosporidium and Giardia are of public health importance, with recognized transmission through recreational waters. Therefore, both can contaminate marine waters and shellfish, with potential to infect marine mammals in nearshore ecosystems. A 2-year study was conducted to evaluate the presence of Cryptosporidium and Giardia in mussels located at two distinct coastal areas in California, namely, (i) land runoff plume sites and (ii) locations near sea lion haul-out sites, as well as in feces of California sea lions (CSL) (Zalophus californianus) by the use of direct fluorescent antibody (DFA) detection methods and PCR with sequence analysis. In this study, 961 individual mussel hemolymph samples, 54 aliquots of pooled mussel tissue, and 303 CSL fecal samples were screened. Giardia duodenalis assemblages B and D were detected in hemolymph from mussels collected near two land runoff plume sites (Santa Rosa Creek and Carmel River), and assemblages C and D were detected in hemolymph from mussels collected near a sea lion haul-out site (White Rock). These results suggest that mussels are being contaminated by protozoa carried in terrestrial runoff and/or shed in the feces of CSL. Furthermore, low numbers of oocysts and cysts morphologically similar to Cryptosporidium and Giardia, respectively, were detected in CSL fecal samples, suggesting that CSL could be a source and a host of protozoan parasites in coastal environments. The results of this study showed that Cryptosporidium and Giardia spp. from the feces of terrestrial animals and CSL can contaminate mussels and coastal environments. PMID:25281384

Molecular epidemiology of Cryptosporidium spp. and Giardia spp. in mussels (Mytilus californianus) and California sea lions (Zalophus californianus) from Central California.

PubMed

Adell, A D; Smith, W A; Shapiro, K; Melli, A; Conrad, P A

2014-12-01

Cryptosporidium and Giardia are of public health importance, with recognized transmission through recreational waters. Therefore, both can contaminate marine waters and shellfish, with potential to infect marine mammals in nearshore ecosystems. A 2-year study was conducted to evaluate the presence of Cryptosporidium and Giardia in mussels located at two distinct coastal areas in California, namely, (i) land runoff plume sites and (ii) locations near sea lion haul-out sites, as well as in feces of California sea lions (CSL) (Zalophus californianus) by the use of direct fluorescent antibody (DFA) detection methods and PCR with sequence analysis. In this study, 961 individual mussel hemolymph samples, 54 aliquots of pooled mussel tissue, and 303 CSL fecal samples were screened. Giardia duodenalis assemblages B and D were detected in hemolymph from mussels collected near two land runoff plume sites (Santa Rosa Creek and Carmel River), and assemblages C and D were detected in hemolymph from mussels collected near a sea lion haul-out site (White Rock). These results suggest that mussels are being contaminated by protozoa carried in terrestrial runoff and/or shed in the feces of CSL. Furthermore, low numbers of oocysts and cysts morphologically similar to Cryptosporidium and Giardia, respectively, were detected in CSL fecal samples, suggesting that CSL could be a source and a host of protozoan parasites in coastal environments. The results of this study showed that Cryptosporidium and Giardia spp. from the feces of terrestrial animals and CSL can contaminate mussels and coastal environments. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Intestinal parasites in cancer patients in the South of Brazil.

PubMed

Jeske, S; Bianchi, T F; Moura, M Q; Baccega, B; Pinto, N B; Berne, M E A; Villela, M M

2017-11-27

Intestinal parasitic infections in immunocompromised patients can lead to serious complications when not diagnosed and treated early. This study aimed to investigate the frequency of intestinal parasites in cancer patients undergoing chemotherapy in the South of Brazil. Three fecal samples collected from each patient (73 individuals) were processed by Ritchie and Faust techniques and submitted to specific staining methods for intestinal protozoa. A 61.6% parasite and/or commensal positivity was found. Helminths identified were Ascaris lumbricoides (33.3%), Taenia spp. (6.6%), Strongyloides stercoralis (4.4%) and Trichuris trichiura (2.2%). Among protozoans, Giardia lamblia (26.6%), Cryptosporidium spp. (13.3%) and Cystoisospora belli (4.4%) were identified. The presence of Entamoeba coli, Endolimax nana and Entamoeba hartmanni was also recorded. The results obtained warn of the importance of fecal parasitological diagnosis and the use of specific staining methods for the detection of intestinal parasites in cancer patients. These exams should be regularly requested at the patient's first clinic visit, given the high prevalence found in this study and the possible severity of such conditions for these individuals.

The Prevalence of Blastocystis hominis and Other Protozoan Parasites in Soldiers Returning from Peacekeeping Missions

PubMed Central

Duda, Aleksandra; Kosik-Bogacka, Danuta; Lanocha-Arendarczyk, Natalia; Kołodziejczyk, Lidia; Lanocha, Aleksandra

2015-01-01

Blastocystis hominis is a common intestinal parasite found in humans living in poor sanitary conditions, living in tropical and subtropical climates, exposed to infected animals, or consuming contaminated food or water. The aim of this study was to determine the prevalence of B. hominis in Polish military personnel returning from peacekeeping missions in Iraq and Afghanistan. In total, 1,826 stool samples were examined. Gastrointestinal parasites were detected in 17% of the soldiers. The examined stool samples most frequently contained vacuolar forms of B. hominis (15.3%) and cysts of Entamoeba coli (1.0%) or Giardia lamblia (0.7%). In 97.1% of stool samples from infected soldiers, we observed less than five developmental forms of B. hominis in the field of view (40×). The parasite infections in soldiers were diagnosed in the autumn and the spring. There was no statistical correlation between age and B. hominis infection. Our results show that peacekeeping missions in countries with tropical or subtropical climates could be associated with risk for parasitic diseases, including blastocystosis. PMID:25732683

Evaluating Cryptosporidium and Giardia concentrations in combined sewer overflow.

PubMed

Arnone, Russell D; Walling, Joyce Perdek

2006-06-01

Since the first identified Cryptosporidium outbreaks occurred in the 1980s and the massive 1993 Milwaukee, WI outbreak affected more than 400,000 people, the concern over the public health risks linked to protozoan pathogens Cryptosporidium and Giardia has grown. Cryptosporidium and Giardia, found in streams, rivers, groundwater, and soil, form hardy, disinfection-resistant oocysts and cysts. Both organisms are recognized causative agents of gastrointestinal illnesses linked to the consumption of contaminated surface or groundwater. This study, the first in a planned series to estimate the urban contribution to the total Cryptosporidium and Giardia receiving-water loads, focused on combined sewer overflow (CSO). CSOs are discharges of mixed untreated sewage and stormwater released directly into receiving waters during rainfall. This engineered relief is necessary to accommodate hydraulic strain when the combined rain and sanitary flows exceed the system capacity. Limited comprehensive data are available assessing the CSO discharge contribution as a source of these two pathogens. Works by States et al. and Gibson et al. each found Cryptosporidium and much greater Giardia concentrations in CSOs draining parts of Pittsburgh, PA. This project estimated the relative detection frequency and concentration of Cryptosporidium and Giardia in CSO. Analytical results were obtained using a modification of Method 1623, originally developed for much cleaner environmental samples. These data are useful for drinking water treatment plants located downstream of CSOs. It is also significant in determining the potential concentrations of parasites at treatment plant intakes and for assessing health risks for water contact and fishing activities. Commonly monitored indicator organisms (total coliform, fecal coliform, E. coli, Enterococcus, and fecal streptococcus), endospores, and selected physical and chemical parameters were analyzed to further describe the samples. CSO from urban areas was not found to be a significant contributor of Cryptosporidium, however, it was found to be a Giardia source.

Control of Giardia infections with ronidazole and intensive hygiene management in a dog kennel.

PubMed

Fiechter, Ruth; Deplazes, Peter; Schnyder, Manuela

2012-06-08

Infections with the intestinal protozoan parasite Giardia in dogs and cats are common. Clinical signs vary from asymptomatic to small bowel diarrhea and associated discomfort. The control of infections in dogs is frequently a frustrating issue for animal owners and veterinarians. Drugs with antiprotozoal activity such as fenbendazole and metronidazole are recommended, however, they do not show 100% efficacy and superinfections occur regularly. Ronidazole is currently the drug of choice for the treatment of Tritrichomonas foetus in cats and there is now limited information available about its efficacy against Giardia spp. In the kennel investigated, dogs regularly showed loose feces and the presence of Giardia (assemblage C, renamed as G. canis) cysts. An elimination strategy of this parasite involving strict hygiene management and disinfection of the enclosures with 4-chlorine-M-cresol, oral treatment with ronidazole (30-50mg/kg BW bid for 7 days) and two shampooings (containing chlorhexidine) at the beginning and the end of the treatments was implemented for a group of 6 dogs. As a control another group of 7 dogs was transferred to the disinfected enclosures and shampooed, but left untreated. Dog feces were tested for the presence of Giardia cysts (SAF concentration technique) or Giardia antigen with a commercial ELISA (NOVITEC(®)) and a quick immunochromatography-based test (SensPERT(®)) before and between 5 and 40 days after the last treatment. All ronidazole-treated dogs were negative for Giardia cysts and antigen up to 26 days after the last treatment, while between 1 and 5 of the control animals tested positive in each of the test series. At this point, also dogs of the control group were again moved into clean enclosures, shampooed twice and treated with ronidazole. Five, 12 and 19 days after the last treatment, the dogs in the control group tested negative for Giardia cysts and antigen. However, all animals had again positive results at later time points in at least one of the three applied diagnostic techniques within 33-61 days after treatment. Furthermore, all dogs had episodes of diarrhea (for 1-4 days) within 14-31 days after treatment and unformed feces during the whole experiment. The positive effect of ronidazole against Giardia infections in dogs could be confirmed in this study. In particular, the combination of ronidazole treatment combined with the disinfection of the environment and shampooing of the dogs was highly effective in reducing Giardia cyst excretion and may therefore constitute an alternative control strategy for canine giardiosis. Copyright © 2011 Elsevier B.V. All rights reserved.

Plasmid Vectors for Proteomic Analyses in Giardia: Purification of Virulence Factors and Analysis of the Proteasome

PubMed Central

Stadelmann, Britta; Birkestedt, Sandra; Hellman, Ulf; Svärd, Staffan G.

2012-01-01

In recent years, proteomics has come of age with the development of efficient tools for purification, identification, and characterization of gene products predicted by genome projects. The intestinal protozoan Giardia intestinalis can be transfected, but there is only a limited set of vectors available, and most of them are not user friendly. This work delineates the construction of a suite of cassette-based expression vectors for use in Giardia. Expression is provided by the strong constitutive ornithine carbamoyltransferase (OCT) promoter, and tagging is possible in both N- and C-terminal configurations. Taken together, the vectors are capable of providing protein localization and production of recombinant proteins, followed by efficient purification by a novel affinity tag combination, streptavidin binding peptide–glutathione S-transferase (SBP-GST). The option of removing the tags from purified proteins was provided by the inclusion of a PreScission protease site. The efficiency and feasibility of producing and purifying endogenous recombinant Giardia proteins with the developed vectors was demonstrated by the purification of active recombinant arginine deiminase (ADI) and OCT from stably transfected trophozoites. Moreover, we describe the tagging, purification by StrepTactin affinity chromatography, and compositional analysis by mass spectrometry of the G. intestinalis 26S proteasome by employing the Strep II-FLAG–tandem affinity purification (SF-TAP) tag. This is the first report of efficient production and purification of recombinant proteins in and from Giardia, which will allow the study of specific parasite proteins and protein complexes. PMID:22611020

Presence of parasitic protozoa and helminth in sewage and efficiency of sewage treatment in Tunisia.

PubMed

Ben Ayed, L; Schijven, J; Alouini, Z; Jemli, M; Sabbahi, S

2009-08-01

Helminth eggs and protozoan cysts were enumerated in raw and treated wastewater in Tunisia in order to determine their removal by wastewater treatment and to provide quantitative data for developing regulations for wastewater quality that are currently lacking. Raw and treated wastewater samples were collected from 17 plants in Tunisia during 2006-2007 and analyzed for parasites using the modified Bailenger method. Two groups of parasites, namely, Ascaris sp., Entamoeba coli, Enterobius vermicularis, and Taenia sp. (group 1) and Entamoeba histolytica/dispar, Giardia sp., and Taenia sp. (group 2) could statistically be distinguished according to their removal by wastewater treatment. Group 1 parasites were removed by 1.1 log(10) (92.4%) and group 2 parasites by 0.61 log(10) (76%). The ubiquitous presence of parasitic protozoa in Tunisian wastewater and ineffective wastewater treatment lead to their proliferation in surface waters with a high probability of exposure of human and animals to these parasites and consequent adverse health effects, as is apparent from epidemiologic data as well. This study provides a quantitative basis for risk assessment studies and development of mitigation strategies, such as improving wastewater treatment efficiency.

Detection and prevalence of protozoan parasites in ready-to-eat packaged salads on sale in Italy.

PubMed

Caradonna, Tiziana; Marangi, Marianna; Del Chierico, Federica; Ferrari, Nicola; Reddel, Sofia; Bracaglia, Giorgia; Normanno, Giovanni; Putignani, Lorenza; Giangaspero, Annunziata

2017-10-01

To investigate the prevalence of protozoan contamination by Giardia duodenalis, Cryptosporidium spp., Toxoplasma gondii and Cyclospora cayetanensis, in 'ready to eat' (RTE) salads on sale in Italy, 648 packages were purchased from industrial and local brands. Nine individual packages from each brand were collected per month, pooled and subjected to microscopy and molecular analyses. Microscopic examination of 864 slides detected Cryptosporidium spp. but also Blastocystis hominis and Dientamoeba fragilis. Molecular tools identified G. duodenalis assemblage A, Cryptosporidium parvum and Cryptosporidium ubiquitum, T. gondii Type I and C. cayetanensis. B. hominis and D. fragilis were also molecularly confirmed. The overall prevalence of each protozoan species was 0.6% for G. duodenalis, 0.8% for T. gondii, 0.9% for Cryptosporidium spp., and 1.3% for C. cayetanensis, while prevalence for B. hominis was 0.5% and for D. fragilis 0.2%. Microscopy and/or molecular tools revealed that 4.2% of the samples were contaminated by at least one protozoan species, and 0.6% of samples presented contamination by two protozoan species, with a number of oocysts ranging from 62 to 554 per g of vegetable matter for T. gondii, and 46 to 1.580 for C. cayetanensis. This is Europe's first large-scale study on the presence of protozoans in packaged salads, and shows that RTE sanitation processes do not guarantee a product free from protozoans of fecal origin. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quantification of Protozoa and Viruses from Small Water Volumes

PubMed Central

Bonilla, J. Alfredo; Bonilla, Tonya D.; Abdelzaher, Amir M.; Scott, Troy M.; Lukasik, Jerzy; Solo-Gabriele, Helena M.; Palmer, Carol J.

2015-01-01

Large sample volumes are traditionally required for the analysis of waterborne pathogens. The need for large volumes greatly limits the number of samples that can be processed. The goals of this study were to compare extraction and detection procedures for quantifying protozoan parasites and viruses from small volumes of marine water. The intent was to evaluate a logistically simpler method of sample collection and processing that would facilitate direct pathogen measures as part of routine monitoring programs. Samples were collected simultaneously using a bilayer device with protozoa capture by size (top filter) and viruses capture by charge (bottom filter). Protozoan detection technologies utilized for recovery of Cryptosporidium spp. and Giardia spp. were qPCR and the more traditional immunomagnetic separation—IFA-microscopy, while virus (poliovirus) detection was based upon qPCR versus plaque assay. Filters were eluted using reagents consistent with the downstream detection technologies. Results showed higher mean recoveries using traditional detection methods over qPCR for Cryptosporidium (91% vs. 45%) and poliovirus (67% vs. 55%) whereas for Giardia the qPCR-based methods were characterized by higher mean recoveries (41% vs. 28%). Overall mean recoveries are considered high for all detection technologies. Results suggest that simultaneous filtration may be suitable for isolating different classes of pathogens from small marine water volumes. More research is needed to evaluate the suitability of this method for detecting pathogens at low ambient concentration levels. PMID:26114244

Quantification of Protozoa and Viruses from Small Water Volumes.

PubMed

Bonilla, J Alfredo; Bonilla, Tonya D; Abdelzaher, Amir M; Scott, Troy M; Lukasik, Jerzy; Solo-Gabriele, Helena M; Palmer, Carol J

2015-06-24

Large sample volumes are traditionally required for the analysis of waterborne pathogens. The need for large volumes greatly limits the number of samples that can be processed. The aims of this study were to compare extraction and detection procedures for quantifying protozoan parasites and viruses from small volumes of marine water. The intent was to evaluate a logistically simpler method of sample collection and processing that would facilitate direct pathogen measures as part of routine monitoring programs. Samples were collected simultaneously using a bilayer device with protozoa capture by size (top filter) and viruses capture by charge (bottom filter). Protozoan detection technologies utilized for recovery of Cryptosporidium spp. and Giardia spp. were qPCR and the more traditional immunomagnetic separation-IFA-microscopy, while virus (poliovirus) detection was based upon qPCR versus plaque assay. Filters were eluted using reagents consistent with the downstream detection technologies. Results showed higher mean recoveries using traditional detection methods over qPCR for Cryptosporidium (91% vs. 45%) and poliovirus (67% vs. 55%) whereas for Giardia the qPCR-based methods were characterized by higher mean recoveries (41% vs. 28%). Overall mean recoveries are considered high for all detection technologies. Results suggest that simultaneous filtration may be suitable for isolating different classes of pathogens from small marine water volumes. More research is needed to evaluate the suitability of this method for detecting pathogens at low ambient concentration levels.

Fine-Scale Spatial Heterogeneity in the Distribution of Waterborne Protozoa in a Drinking Water Reservoir

PubMed Central

Burnet, Jean-Baptiste; Ogorzaly, Leslie; Penny, Christian; Cauchie, Henry-Michel

2015-01-01

Background: The occurrence of faecal pathogens in drinking water resources constitutes a threat to the supply of safe drinking water, even in industrialized nations. To efficiently assess and monitor the risk posed by these pathogens, sampling deserves careful design, based on preliminary knowledge on their distribution dynamics in water. For the protozoan pathogens Cryptosporidium and Giardia, only little is known about their spatial distribution within drinking water supplies, especially at fine scale. Methods: Two-dimensional distribution maps were generated by sampling cross-sections at meter resolution in two different zones of a drinking water reservoir. Samples were analysed for protozoan pathogens as well as for E. coli, turbidity and physico-chemical parameters. Results: Parasites displayed heterogeneous distribution patterns, as reflected by significant (oo)cyst density gradients along reservoir depth. Spatial correlations between parasites and E. coli were observed near the reservoir inlet but were absent in the downstream lacustrine zone. Measurements of surface and subsurface flow velocities suggest a role of local hydrodynamics on these spatial patterns. Conclusion: This fine-scale spatial study emphasizes the importance of sampling design (site, depth and position on the reservoir) for the acquisition of representative parasite data and for optimization of microbial risk assessment and monitoring. Such spatial information should prove useful to the modelling of pathogen transport dynamics in drinking water supplies. PMID:26404350

Occurrence, prevalence and intensity of internal parasite infections of African lions (Panthera leo) in enclosures at a recreation park in Zimbabwe.

PubMed

Mukarati, Norman L; Vassilev, George D; Tagwireyi, Whatmore M; Tavengwa, Michael

2013-09-01

A coprological survey was conducted to determine the types, prevalence, and intensity of infection of internal parasites in a population of captive African lions (Panthera leo) at a recreational game park in Zimbabwe. Individual fecal samples were collected on three occasions over a 4-month period from each of 30 lions (55%) out of 55 animals held. The samples were examined using flotation and sedimentation techniques to assess the presence and count of parasite eggs, oocysts, and cysts per gram of feces as well as larvae identification. The overall prevalence of helminth infections was 100% (30/30), and 80% (24/30) of fecal samples also were positive for protozoan parasite forms. Eggs of Ancylostoma spp. were found in the feces of 23 (76.7%) lions, Physaloptera sp. in 14 (46.7%) lions, Toxascaris leonina in 13 (43.3%) lions, Toxocara cati in 12 (40%) lions, and Gnathostoma spinigerum and Toxocara canis in 2 (6.7%) lions. Furthermore, eggs of Cylicospirura subequalis, Gnathostoma spp., Lagochilascaris major, Acanthocephalan and Linguatula spp. as well as larvae of Aelurostrongylus sp. were identified in the feces of one lion. Oocysts of five apicomplexan parasites and cysts of one mastigophoran protozoan parasite were recorded, namely, Cystoisospora leonina in 11 (36.7%) lions' feces, Cystoisospora spp. in 9 (30.0%) lions, Cystoisospora felis in 5 (16.7%) lions; Toxoplasma-like spp. in 5 (16.7 %) lions, and Giardia spp. in 8 (26.7%) lions. The majority of lions (28/30) showed mixed infections with different internal parasites, whereas only two animals had single parasite infections. The intensity of infection was relatively low. Some parasite forms observed and identified, such as Eimeria spp. oocysts, were spurious and probably originated from the prey species for the lions. Among the parasites identified were some of zoonotic importance that have health implications for at-risk personnel and visitors who get into contact with the animals.

Examination of anonymous canine faecal samples provides data on endoparasite prevalence rates in dogs for comparative studies.

PubMed

Hinney, Barbara; Gottwald, Michaela; Moser, Jasmine; Reicher, Bianca; Schäfer, Bhavapriya Jasmin; Schaper, Roland; Joachim, Anja; Künzel, Frank

2017-10-15

Several endoparasites of dogs cannot only be detrimental to their primary host but might also represent a threat to human health because of their zoonotic potential. Due to their high dog population densities, metropolitan areas can be highly endemic for such parasites. We aimed to estimate the prevalence of endoparasites in dogs in the Austrian capital of Vienna by examining a representative number of canine faecal samples and to compare the prevalences with two neighbouring peri-urban and rural regions. In addition we analysed whether the density of dog populations and cleanliness of dog zones correlated with parasite occurrence. We collected 1001 anonymous faecal samples from 55 dog zones from all 23 districts of the federal state of Vienna, as well as 480 faecal samples from the Mödling district and Wolkersdorf with a peri-urban and rural character, respectively. Faeces were examined by flotation and by Baermann technique. Additionally we evaluated 292 Viennese, 102 peri-urban and 50 rural samples for Giardia and Cryptosporidium by GiardiaFASTest ® and CryptoFASTest ® . Samples from "clean" dog zones were compared to samples from "dirty" zones. The infection rate of Toxocara was surprisingly low, ranging from 0.6% to 1.9%. Trichuris was the most frequent helminth (1.8-7.5%) and Giardia the most frequent protozoan (4.0-10.8%). Ancylostomatidae, Crenosoma, Capillaria, Taeniidae, Cystoisospora and Sarcocystis were found in 1.8-2.2%, 0-0.9%, 0-0.9%, 0-0.6%, 0.3-3.1% and 0-0.6% of the samples, respectively. Samples from "dirty" dog zones in Vienna showed a significantly higher rate of parasites overall (p=0.003) and of Trichuris (p=0.048) compared to samples from "clean" dog zones. There were no statistically significant differences in densely vs. less densely populated areas of Vienna. Samples from the rural region of Wolkersdorf had significantly higher overall parasite, Trichuris and Cystoisospora prevalences than the peri-urban Mödling district and Vienna (p=0.000-0.039), while samples from the Mödling district had a significantly higher Giardia, Crenosoma and Capillaria prevalence than those from Vienna (p=0.002-0.047). Parasite excretion is dynamic and representative sampling and monitoring are necessary for parasite surveillance. Dog owners should be informed about the zoonotic risk and encouraged to remove dog faeces and dispose of them properly to reduce the infection risk for both other dogs and humans. Copyright © 2017 Elsevier B.V. All rights reserved.

Removal of Giardia spp. and Cryptosporidium spp. from water supply with high turbidity: analytical challenges and perspectives.

PubMed

Maciel, P M F; Sabogal-Paz, L P

2016-06-01

Giardia and Cryptosporidium species are a serious problem if present in water supplies. The removal of these protozoans and the adaptation of existing protocols are essential for supplying drinking water to developing countries. Considering this, the aim of this study is to evaluate, on a bench level, the removal of Giardia spp. cysts and of Cryptosporidium spp. oocysts from water with high turbidity, using polyaluminium chloride as a coagulant. Filtration using mixed cellulose ester membranes, followed, or not, by purification through immunomagnetic separation (IMS) was used for detecting protozoans. By evaluating the adopted protocol, without using IMS, retrievals of 80% of cysts and 5% of oocysts were obtained, whereas by using IMS, recoveries of 31.5% of cysts and 5.75% of oocysts were reached. When analyzing the coagulant performance, a dosage of 65 mg L(-1) showed contamination from protozoans in all the samples of filtered water. A dosage of 25 mg L(-1) presented protozoans in 50% of the filtered water samples. The results showed an improved performance for the 25 mg L(-1) dosage; therefore, the control of coagulation and adaptation of detection protocols must be evaluated according to the features of raw water and availability of local resources.

Stool antigen immunodetection for diagnosis of Giardia duodenalis infection in human subjects with HIV and cancer.

PubMed

Nooshadokht, Maryam; Kalantari-Khandani, Behjat; Sharifi, Iraj; Kamyabi, Hossein; Liyanage, Namal P M; Lagenaur, Laurel A; Kagnoff, Martin F; Singer, Steven M; Babaei, Zahra; Solaymani-Mohammadi, Shahram

2017-10-01

Human infection with the protozoan parasite Giardia duodenalis is one the most common parasitic diseases worldwide. Higher incidence rates of giardiasis have been reported from human subjects with multiple debilitating chronic conditions, including hypogammaglobulinemia and common variable immunodeficiency (CVID). In the current study, stool specimens were collected from 199 individuals diagnosed with HIV or cancer and immunocompetent subjects. The sensitivity of microscopy-based detection on fresh stool preparations, trichrome staining and stool antigen immunodetection for the diagnosis of G. duodenalis were 36%, 45.5% and 100%, respectively when compared with a highly sensitive stool-based PCR method as the gold standard. Further multilocus molecular analyses using glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) loci demonstrated that the AI genotype of G. duodenalis was the most prevalent, followed by the AII genotype and mixed (AI+B) infections. We concluded that stool antigen immunodetection-based immunoassays and stool-based PCR amplification had comparable sensitivity and specificity for the diagnosis of G. duodenalis infections in these populations. Stool antigen detection-based diagnostic modalities are rapid and accurate and may offer alternatives to conventional microscopy and PCR-based diagnostic methods for the diagnosis of G. duodenalis in human subjects living with HIV or cancer. Copyright © 2017. Published by Elsevier B.V.

CRITERIA FOR EVALUATION OF PROPOSED PROTOZOAN DETECTION METHODS

EPA Science Inventory

There has been a proliferation of techniques and methods reported for analysis of water samples to determine the presence of the protozoan pathogens Cryptosporidium parvum and Giardia lamblia. Many of the proposed methods are presented as complete procedures, which include sampli...

CRITERIA FOR EVALUATION OF PROPOSED PROTOZOAN DETECTION METHODS.

EPA Science Inventory

There has been a proliferation of techniques and methods reported for analysis of water samples to determine the presence of the protozoan pathogens Cryptosporidium parvum and Giardia lamblia. Many of the proposed methods are presented as complete procedures, which include sampli...

Prevalence of Giardia duodenalis and Cryptosporidium species infections among children and cattle in North Shewa Zone, Ethiopia.

PubMed

Wegayehu, Teklu; Adamu, Haileeyesus; Petros, Beyene

2013-09-08

Giardia and Cryptosporidium are the most common causes of protozoan diarrhea that lead to significant morbidity and mortality worldwide. The purpose of this study was to determine the prevalence of Giardia duodenalis and Cryptosporidium species infections among children and cattle, and to assess the potential risk of zoonotic transmission. This cross-sectional study was conducted between January and April 2009 in Girar Jarso and Dera Districts of North Shewa Zone, Oromia Region, Ethiopia. A total of 768 stool specimens were collected and examined for intestinal parasites using direct wet mount with saline and formalin ether concentration methods. The modified Ziehl-Neelsen staining method was used for the detection of Cryptosporidium species. Statistical analysis was performed using SPSS software version 15. Out of 384 children examined, 53 (13.8%) and 28 (7.3%) were positive for Giardia and Cryptosporidium infections, respectively. Similarly, of the total 384 cattle examined, 9 (2.3%) were positive for Giardia duodenalis and 30 (7.8%) were positive for Cryptosporidium infection. The prevalence of giardiasis was significantly higher among children who had close contact with cattle 33 (18.7%) compared to children who had no contact with cattle 20 (9.6%) (P < 0.05). Higher number of Cryptosporidium infection was also recorded in children who had close contact with cattle 15 (8.5%). Difference in prevalence of giardiasis and cryptosporidiosis among children was not statistically significant between males and females. On the other hand, difference in the prevalence of giardiasis among children was statistically significant between age groups. Higher prevalence of Giardia duodenalis infection detected among children was significantly associated with contact with cattle and manure that the children had. Further analysis using molecular techniques is needed to explain the existence of zoonotic transmission in the study area.

Irritable bowel syndrome and chronic fatigue 6 years after giardia infection: a controlled prospective cohort study.

PubMed

Hanevik, Kurt; Wensaas, Knut-Arne; Rortveit, Guri; Eide, Geir Egil; Mørch, Kristine; Langeland, Nina

2014-11-15

Functional gastrointestinal disorders and fatigue may follow acute infections. This study aimed to estimate the persistence, prevalence, and risk of irritable bowel syndrome and chronic fatigue 6 years after Giardia infection. We performed a controlled prospective study of a cohort of 1252 individuals who had laboratory-confirmed Giardia infection during a waterborne outbreak in 2004. In total, 748 cohort cases (exposed) and 878 matched controls responded to a postal questionnaire 6 years later (in 2010). Responses were compared to data from the same cohort 3 years before (in 2007). The prevalences of irritable bowel syndrome (39.4%) by Rome III criteria and chronic fatigue (30.8%) in the exposed group 6 years after giardiasis were significantly elevated compared with controls, with adjusted relative risks (RRs) of 3.4 (95% confidence interval [CI], 2.9-3.9) and 2.9 (95% CI, 2.3-3.4), respectively. In the exposed group, the prevalence of irritable bowel syndrome decreased by 6.7% (RR, 0.85 [95% CI, .77-.93]), whereas the prevalence of chronic fatigue decreased by 15.3% from 3 to 6 years after Giardia infection (RR, 0.69 [95% CI, .62-.77]). Giardia exposure was a significant risk factor for persistence of both conditions, and increasing age was a risk factor for persisting chronic fatigue. Giardia infection in a nonendemic setting is associated with an increased risk for irritable bowel syndrome and chronic fatigue 6 years later. The prevalences of both conditions decrease over time, indicating that this intestinal protozoan parasite may elicit very long-term, but slowly self-limiting, complications. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

Central importance of immunoglobulin A in host defense against Giardia spp.

PubMed

Langford, T Dianne; Housley, Michael P; Boes, Marianne; Chen, Jianzhu; Kagnoff, Martin F; Gillin, Frances D; Eckmann, Lars

2002-01-01

The protozoan pathogen Giardia is an important cause of parasitic diarrheal disease worldwide. It colonizes the lumen of the small intestine, suggesting that effective host defenses must act luminally. Immunoglobulin A (IgA) antibodies are presumed to be important for controlling Giardia infection, but direct evidence for this function is lacking. B-cell-independent effector mechanisms also exist and may be equally important for antigiardial host defense. To determine the importance of the immunoglobulin isotypes that are transported into the intestinal lumen, IgA and IgM, for antigiardial host defense, we infected gene-targeted mice lacking IgA-expressing B-cells, IgM-secreting B-cells, or all B-cells as controls with Giardia muris or Giardia lamblia GS/M-83-H7. We found that IgA-deficient mice could not eradicate either G. muris or G. lamblia infection, demonstrating that IgA is required for their clearance. Furthermore, although neither B-cell-deficient nor IgA-deficient mice could clear G. muris infections, IgA-deficient mice controlled infection significantly better than B-cell-deficient mice, suggesting the existence of B-cell-dependent but IgA-independent antigiardial defenses. In contrast, mice deficient for secreted IgM antibodies cleared G. muris infection normally, indicating that they have no unique functions in antigiardial host defense. These data, together with the finding that B-cell-deficient mice have some, albeit limited, residual capacity to control G. muris infection, show that IgA-dependent host defenses are central for eradicating Giardia spp. Moreover, B-cell-dependent but IgA-independent and B-cell-independent antigiardial host defenses exist but are less important for controlling infection.

An audit of Cryptosporidium and Giardia detection in Scottish National Health Service Diagnostic Microbiology Laboratories.

PubMed

Alexander, C L; Currie, S; Pollock, K; Smith-Palmer, A; Jones, B L

2017-06-01

Giardia duodenalis and Cryptosporidium species are protozoan parasites capable of causing gastrointestinal disease in humans and animals through the ingestion of infective faeces. Whereas Cryptosporidium species can be acquired locally or through foreign travel, there is the mis-conception that giardiasis is considered to be largely travel-associated, which results in differences in laboratory testing algorithms. In order to determine the level of variation in testing criteria and detection methods between diagnostic laboratories for both pathogens across Scotland, an audit was performed. Twenty Scottish diagnostic microbiology laboratories were invited to participate with questions on sample acceptance criteria, testing methods, testing rates and future plans for pathogen detection. Reponses were received from 19 of the 20 laboratories representing each of the 14 territorial Health Boards. Detection methods varied between laboratories with the majority performing microscopy, one using a lateral flow immunochromatographic antigen assay, another using a manually washed plate-based enzyme immunoassay (EIA) and one laboratory trialling a plate-based EIA automated with an EIA plate washer. Whereas all laboratories except one screened every stool for Cryptosporidium species, an important finding was that significant variation in the testing algorithm for detecting Giardia was noted with only four laboratories testing all diagnostic stools. The most common criteria were 'travel history' (11 laboratories) and/or 'when requested' (14 laboratories). Despite only a small proportion of stools being examined in 15 laboratories for Giardia (2%-18% of the total number of stools submitted), of interest is the finding that a higher positivity rate was observed for Giardia than Cryptosporidium in 10 of these 15 laboratories. These findings highlight that the underreporting of Giardia in Scotland is likely based on current selection and testing algorithms.

EVALUATING CRYPTOSPORIDIUM AND GIARDIA CONCENTRATIONS IN COMBINED SEWER OVERFLOW

EPA Science Inventory

Since the first identified Cryptosporidium outbreaks occurred in the 1980s and the massive 1993 Milwaukee, WI outbreak affected more than 400,000 people (Fox & Lytle 1996), the concern over the public health risks linked to protozoan pathogens Cryptosporidium and Giardia has grow...

Decreasing Intestinal Parasites in Recent Northern California Refugees

PubMed Central

Chang, Alicia H.; Perry, Sharon; Du, Jenny N. T.; Agunbiade, Abdulkareem; Polesky, Andrea; Parsonnet, Julie

2013-01-01

Beginning in 2005, the Centers for Disease Control and Prevention (CDC) expanded the overseas presumptive treatment of intestinal parasites with albendazole to include refugees from the Middle East. We surveyed the prevalence of helminths and protozoa in recent Middle Eastern refugees (2008–2010) in comparison with refugees from other geographical regions and from a previous survey (2001–2004) in Santa Clara County, California. Based on stool microscopy, helminth infections decreased, particularly in Middle Eastern refugees (0.1% versus 2.3% 2001–2004, P = 0.01). Among all refugees, Giardia intestinalis was the most common protozoan found. Protozoa infections also decreased somewhat in Middle Eastern refugees (7.2%, 2008–2010 versus 12.9%, 2001–2004, P = 0.08). Serology for Strongyloides stercoralis and Schistosoma spp. identified more infected individuals than stool exams. Helminth infections are increasingly rare in refugees to Northern California. Routine screening stool microscopy may be unnecessary in all refugees. PMID:23149583

Study of the gastrointestinal parasitic fauna of captive non-human primates (Macaca fascicularis).

PubMed

Zanzani, Sergio Aurelio; Gazzonis, Alessia Libera; Epis, Sara; Manfredi, Maria Teresa

2016-01-01

The aim of this study was to examine helminths and protozoans in cynomolgus macaques (Macaca fascicularis) imported from registered breeding facilities in China and their relation to health risks for non-human primate handlers in biomedical research centers and in breeding facilities. Fresh fecal samples were collected from a total of 443 M. fascicularis and analyzed by copromicroscopical analysis, immunoenzymatic, or molecular assays. As to helminths, whose eggs were shed in 2.03% of the samples, Trichuris and Oesophagostomum were the only two taxa found, with low prevalence and low eggs per gram (EPG) values. Protozoans were more frequently detected (87.40%), with Entamoeba coli (85.19%) and Endolimax nana (79.26%) as the most prevalent species shed. Other parasites found by fecal smear examination were uninucleated-cyst-producing Entamoebas (78.52%), Iodamoeba bütschlii (42.96%), and Chilomastix mesnili (24.44%), while cysts of Balantidium coli (22.2%) were only observed by sedimentation. No coproantigens of Giardia duodenalis, Cryptosporidium spp., and Entamoeba histolytica complex were detected. Blastocystis sp. infection was noticed in 87.63% of macaques by PCR. These cynomolgus monkeys were infected with many subtypes (ST1, ST2, ST3, ST5, and ST7), where the predominant Blastocystis sp. subtypes were ST2 (77.5%), followed by ST1 (63.5%). Data collected confirmed the presence of potentially zoonotic parasites and a high parasite diversity, suggesting the need for appropriate and sensitive techniques to adequately control them and related health risks for handlers of non-human primates in biomedical research centers and in breeding facilities.

In vitro anti-Giardia lamblia activity of 2-aryl-3-hydroxymethyl imidazo[1,2-a]pyridines and -pyrimidines, individually and in combination with albendazole.

PubMed

Velázquez-Olvera, Stephanía; Salgado-Zamora, Héctor; Jiménez-Cardoso, Enedina; Campos-Aldrete, Maria-Elena; Pérez-González, Cuauhtémoc; Ben Hadda, Taibi

2016-03-01

Giardiasis is a major diarrheal disease found throughout the world, the causative agent being the flagellate protozoan Giardia intestinalis. Infection is more common in children than in adults. The appearance of drug resistance has complicated the treatment of several parasitic diseases, including giardiasis. Thus, the aim of this investigation was to make an in vitro evaluation of the antigiardia response of synthetic derivatives 2-aryl-3-hydroxymethylimidazo[1,2-a]pyridines 1 and -pyrimidines 2 against trophozoites of Giardia lamblia WB, in comparison with the reference drug, albendazole. Additionally, the synergistic action of albendazole in combination with each of the most active 2-aryl-3-hydroxymethyl imidazo[1,2-a]pyridines and pyrimidines was also assessed. Based on the IC50 values obtained, the best anti-Giardia activity was provided by the 3-hydroxymethyl-4-fluorophenylimidazo[1,2-a]pyrimidine derivative 2c and the corresponding imidazo[1,2-a]pyrimidine with the p-tolyl substituent 2d, followed by 2a and 2b. These four compounds showed effectiveness at a concentration similar to that of albendazole. Regarding synergism, the IC50 of the combination of albendazole with 2a, 2b or 2c gave the best anti-Giardia action, showing greater efficacy than albendazole alone. Hence, G. lamblia WB showed high susceptibility to some 2-aryl-3-hydroxymethyl imidazo[1,2-a] pyrimidines, which acted synergistically when used in combination with albendazole. Copyright © 2015 Elsevier B.V. All rights reserved.

Microbiological and parasitological investigation among food handlers in hotels in the Dead Sea area, Jordan.

PubMed

Abdel-Dayem, Muna; Al Zou'bi, Renad; Hani, Rehan Bani; Amr, Zuhair Sami

2014-10-01

Intestinal parasitic and bacterial infections constitute a major health issue in developing countries. The present study investigates and assesses infection rates among food handlers with intestinal parasites and microbial agents in luxurious hotels in the Dead Sea area of Jordan. A total of 901 stool samples were collected from food handlers (35 females and 866 males) employed in four main hotels in the Dead Sea area. Fecal samples were examined microscopically for intestinal parasites. Standard culture and biochemical techniques were used for the isolation and identification of Salmonella and Shigella spp. in stool samples. Five species of protozoan (Blastocystis hominis, Giardia intestinalis, Entamoeba coli, Entamoeba histolytica, and Endolimax nana), one helminth (Hymenolepis nana), and one cylindrical worm (Enterobius vermicularis) were recovered with an overall infection rate of 3.7%. G. intestinalis was the most prevalent parasitic infection with infection rate of 2.44%. All samples were negative for both Salmonella and Shigella. Findings highlight the important role of food handlers in the transmission of intestinal parasites to high-class clients accommodated in luxury hotels, and stress the urgent need for regular health and parasitologic examination of food handlers. Copyright © 2013. Published by Elsevier B.V.

High Throughput Multiplex PCR and Probe-based Detection with Luminex Beads for Seven Intestinal Parasites

PubMed Central

Taniuchi, Mami; Verweij, Jaco J.; Noor, Zannatun; Sobuz, Shihab U.; van Lieshout, Lisette; Petri, William A.; Haque, Rashidul; Houpt, Eric R.

2011-01-01

Polymerase chain reaction (PCR) assays for intestinal parasites are increasingly being used on fecal DNA samples for enhanced specificity and sensitivity of detection. Comparison of these tests against microscopy and copro-antigen detection has been favorable, and substitution of PCR-based assays for the ova and parasite stool examination is a foreseeable goal for the near future. One challenge is the diverse list of protozoan and helminth parasites. Several existing real-time PCR assays for the major intestinal parasites—Cryptosporidium spp., Giardia intestinalis, Entamoeba histolytica, Ancylostoma duodenale, Ascaris lumbricoides, Necator americanus, and Strongyloides stercoralis—were adapted into a high throughput protocol. The assay involves two multiplex PCR reactions, one with specific primers for the protozoa and one with specific primers for the helminths, after which PCR products are hybridized to beads linked to internal oligonucleotide probes and detected on a Luminex platform. When compared with the parent multiplex real-time PCR assays, this multiplex PCR-bead assay afforded between 83% and 100% sensitivity and specificity on a total of 319 clinical specimens. In conclusion, this multiplex PCR-bead protocol provides a sensitive diagnostic screen for a large panel of intestinal parasites. PMID:21292910

Chapter A7. Section 7.3. Protozoan Pathogens

USGS Publications Warehouse

Bushon, Rebecca N.; Francy, Donna S.

2003-01-01

Protozoan pathogens are widely distributed in the aquatic environment. Cryptosporidium and Giardia are the principal protozoan pathogens that are known to affect the acceptability of water supplies for public use within the United States. A sampling program for protozoan pathogens should be conducted over an extended period of time because of cyclical and seasonal variations in their concentrations in the environment. This report provides information on the equipment, sampling protocols, and laboratory method that are in standard use by U.S. Geological Survey (USGS) personnel for the collection of data on protozoan pathogens.

Water quality monitoring using an automated portable fiber optic biosensor: RAPTOR

NASA Astrophysics Data System (ADS)

Anderson, George P.; Rowe-Taitt, Chris A.

2001-03-01

The RAPTOR is a portable, automated biosensor capable of performing rapid, ten-minute assays on a sample for four target analytes simultaneously. Samples are analyzed using a fluorescent sandwich immunoassay on the surface of short polystyrene optical probes with capture antibody adsorbed to the probe surface. Target analytes bound to the fiber by capture antibodies are detected with fluorescently labeled tracer antibodies, which are held in a separate reservoir. Since target recognition is a two-step process, selectivity is enhanced, and the optical probes can be reused up to forty times, or until a positive result is obtained. This greatly reduces the logistical burden for field operations. Numerous assays for toxins, such as SEB and ricin, and bacteria, such as Bacillus anthracis and Francisella tularensis, have been developed for the RAPTOR. An assay of particular interest for water quality monitoring and the screening of fruits and vegetables is detection of Giardia cysts. Giardia lamblia is a parasitic protozoan common in the developing world that causes severe intestinal infections. Thus, a simple field assay for screening water supplies would be highly useful. Such an assay has been developed using the RAPTOR. The detection limit for Giardia cysts was 5x104/ml for a 10-minute assay.

Differences in staining intensities affect reported occurrences and concentrations of Giardia spp. in surface drinking water sources

EPA Science Inventory

Aim USEPA Method 1623, or its equivalent, is currently used to monitor for protozoan contamination of surface drinking water sources worldwide. At least three approved staining kits used for detecting Cryptosporidium and Giardia are commercially available. This study focuses on ...

Intestinal parasites in children and soil from Turbaco, Colombia and associated risk factors.

PubMed

Villafañe-Ferrer, Lucy M; Pinilla-Pérez, Mavianis

2016-02-01

Objective To determine the frequency of intestinal parasites in children and soil from Turbaco- Colombia and associated risks factors. Methods Analytical study in which 390 children between 2 and 12 years old from 10 neighborhoods of Turbaco were included, whose legal representatives gave informed consent. Three serial samples of feces and 10 soil samples were processed. Risk factors were determined through an interview. Physicochemical and structural characteristics of soils were also evaluated. Results Parasites were found in 30.5 % of children. 162 parasites were observed; the most frequent protozoan was Endolimax nana (30.3 %) and in terms of helminthes, the most frequent was Ascaris lumbricoides (4.9 %). No statistical association between age or sex and intestinal parasites (p>0.05) or between risk factors and intestinal parasites (p>0.05) was found. Low frequencies of intestinal parasites were encountered in soil samples, being more common Entamoeba spp., Giardia spp., and Ascaris lumbricoides. Neighborhoods of Turbaco had sandy dry soil with low content of ions, low conductivity and low organic matter. Conclusion This study showed a low frequency of intestinal parasites in feces and soils. Despite this, pathogenic parasites were found which can affect the health of the population. Besides this, a high percentage of intestinal parasites that are transmitted through feces were detected indicating fecal contamination and low level of hygiene.

Bile-Salt-Hydrolases from the Probiotic Strain Lactobacillus johnsonii La1 Mediate Anti-giardial Activity in Vitro and in Vivo.

PubMed

Allain, Thibault; Chaouch, Soraya; Thomas, Myriam; Vallée, Isabelle; Buret, André G; Langella, Philippe; Grellier, Philippe; Polack, Bruno; Bermúdez-Humarán, Luis G; Florent, Isabelle

2017-01-01

Giardia duodenalis (syn. G. lamblia, G. intestinalis ) is the protozoan parasite responsible for giardiasis, the most common and widely spread intestinal parasitic disease worldwide, affecting both humans and animals. After cysts ingestion (through either contaminated food or water), Giardia excysts in the upper intestinal tract to release replicating trophozoites that are responsible for the production of symptoms. In the gut, Giardia cohabits with the host's microbiota, and several studies have revealed the importance of this gut ecosystem and/or some probiotic bacteria in providing protection against G. duodenalis infection through mechanisms that remain incompletely understood. Recent findings suggest that Bile-Salt-Hydrolase (BSH)-like activities from the probiotic strain of Lactobacillus johnsonii La1 may contribute to the anti-giardial activity displayed by this strain. Here, we cloned and expressed each of the three bsh genes present in the L. johnsonii La1 genome to study their enzymatic and biological properties. While BSH47 and BSH56 were expressed as recombinant active enzymes, no significant enzymatic activity was detected with BSH12. In vitro assays allowed determining the substrate specificities of both BSH47 and BSH56, which were different. Modeling of these BSHs indicated a strong conservation of their 3-D structures despite low conservation of their primary structures. Both recombinant enzymes were able to mediate anti-giardial biological activity against Giardia trophozoites in vitro . Moreover, BSH47 exerted significant anti-giardial effects when tested in a murine model of giardiasis. These results shed new light on the mechanism, whereby active BSH derived from the probiotic strain Lactobacillus johnsonii La1 may yield anti-giardial effects in vitro and in vivo . These findings pave the way toward novel approaches for the treatment of this widely spread but neglected infectious disease, both in human and in veterinary medicine.

Bile-Salt-Hydrolases from the Probiotic Strain Lactobacillus johnsonii La1 Mediate Anti-giardial Activity in Vitro and in Vivo

PubMed Central

Allain, Thibault; Chaouch, Soraya; Thomas, Myriam; Vallée, Isabelle; Buret, André G.; Langella, Philippe; Grellier, Philippe; Polack, Bruno; Bermúdez-Humarán, Luis G.; Florent, Isabelle

2018-01-01

Giardia duodenalis (syn. G. lamblia, G. intestinalis) is the protozoan parasite responsible for giardiasis, the most common and widely spread intestinal parasitic disease worldwide, affecting both humans and animals. After cysts ingestion (through either contaminated food or water), Giardia excysts in the upper intestinal tract to release replicating trophozoites that are responsible for the production of symptoms. In the gut, Giardia cohabits with the host's microbiota, and several studies have revealed the importance of this gut ecosystem and/or some probiotic bacteria in providing protection against G. duodenalis infection through mechanisms that remain incompletely understood. Recent findings suggest that Bile-Salt-Hydrolase (BSH)-like activities from the probiotic strain of Lactobacillus johnsonii La1 may contribute to the anti-giardial activity displayed by this strain. Here, we cloned and expressed each of the three bsh genes present in the L. johnsonii La1 genome to study their enzymatic and biological properties. While BSH47 and BSH56 were expressed as recombinant active enzymes, no significant enzymatic activity was detected with BSH12. In vitro assays allowed determining the substrate specificities of both BSH47 and BSH56, which were different. Modeling of these BSHs indicated a strong conservation of their 3-D structures despite low conservation of their primary structures. Both recombinant enzymes were able to mediate anti-giardial biological activity against Giardia trophozoites in vitro. Moreover, BSH47 exerted significant anti-giardial effects when tested in a murine model of giardiasis. These results shed new light on the mechanism, whereby active BSH derived from the probiotic strain Lactobacillus johnsonii La1 may yield anti-giardial effects in vitro and in vivo. These findings pave the way toward novel approaches for the treatment of this widely spread but neglected infectious disease, both in human and in veterinary medicine. PMID:29472895

The biology of Giardia spp.

PubMed Central

Adam, R D

1991-01-01

Gardia spp. are flagellated protozoans that parasitize the small intestines of mammals, birds, reptiles, and amphibians. The infectious cysts begin excysting in the acidic environment of the stomach and become trophozoites (the vegetative form). The trophozoites attach to the intestinal mucosa through the suction generated by a ventral disk and cause diarrhea and malabsorption by mechanisms that are not well understood. Giardia spp. have a number of unique features, including a predominantly anaerobic metabolism, complete dependence on salvage of exogenous nucleotides, a limited ability to synthesize and degrade carbohydrates and lipids, and two nuclei that are equal by all criteria that have been tested. The small size and unique sequence of G. lamblia rRNA molecules have led to the proposal that Giardia is the most primitive eukaryotic organism. Three Giardia spp. have been identified by light lamblia, G. muris, and G. agilis, but electron microscopy has allowed further species to be described within the G. lamblia group, some of which have been substantiated by differences in the rDNA. Animal models and human infections have led to the conclusion that intestinal infection is controlled primarily through the humoral immune system (T-cell dependent in the mouse model). A major immunogenic cysteine-rich surface antigen is able to vary in vitro and in vivo in the course of an infection and may provide a means of evading the host immune response or perhaps a means of adapting to different intestinal environments. Images PMID:1779932

Automated 3D detection and classification of Giardia lamblia cysts using digital holographic microscopy with partially coherent source

NASA Astrophysics Data System (ADS)

El Mallahi, A.; Detavernier, A.; Yourassowsky, C.; Dubois, F.

2012-06-01

Over the past century, monitoring of Giardia lamblia became a matter of concern for all drinking water suppliers worldwide. Indeed, this parasitic flagellated protozoan is responsible for giardiasis, a widespread diarrhoeal disease (200 million symptomatic individuals) that can lead immunocompromised individuals to death. The major difficulty raised by Giardia lamblia's cyst, its vegetative transmission form, is its ability to survive for long periods in harsh environments, including the chlorine concentrations and treatment duration used traditionally in water disinfection. Currently, there is a need for a reliable, inexpensive, and easy-to-use sensor for the identification and quantification of cysts in the incoming water. For this purpose, we investigated the use of a digital holographic microscope working with partially coherent spatial illumination that reduces the coherent noise. Digital holography allows one to numerically investigate a volume by refocusing the different plane of depth of a hologram. In this paper, we perform an automated 3D analysis that computes the complex amplitude of each hologram, detects all the particles present in the whole volume given by one hologram and refocuses them if there are out of focus using a refocusing criterion based on the integrated complex amplitude modulus and we obtain the (x,y,z) coordinates of each particle. Then the segmentation of the particles is processed and a set of morphological and textures features characteristic to Giardia lamblia cysts is computed in order to classify each particles in the right classes.

Interleukin-17 receptor A (IL-17RA) as a central regulator of the protective immune response against Giardia.

PubMed

Paerewijck, Oonagh; Maertens, Brecht; Dreesen, Leentje; Van Meulder, Frederik; Peelaers, Iris; Ratman, Dariusz; Li, Robert W; Lubberts, Erik; De Bosscher, Karolien; Geldhof, Peter

2017-08-17

The protozoan parasite Giardia is a highly prevalent intestinal pathogen with a wide host range. Data obtained in mice, cattle and humans revealed the importance of IL-17A in the development of a protective immune response against Giardia. The aim of this study was to further unravel the protective effector mechanisms triggered by IL-17A following G. muris infection in mice, by an RNA-sequencing approach. C57BL/6 WT and C57BL/6 IL-17RA KO mice were orally infected with G. muris cysts. Three weeks post infection, intestinal tissue samples were collected for RNA-sequencing, with samples from uninfected C57BL/6 WT and C57BL/6 IL-17RA KO animals serving as negative controls. Differential expression analysis showed that G. muris infection evoked the transcriptional upregulation of a wide array of genes, mainly in animals with competent IL-17RA signaling. IL-17RA signaling induced the production of various antimicrobial peptides, such as angiogenin 4 and α- and β-defensins and regulated complement activation through mannose-binding lectin 2. The expression of the receptor that regulates the secretion of IgA into the intestinal lumen, the polymeric immunoglobulin receptor, was also dependent on IL-17RA signaling. Interestingly, the transcriptome data showed for the first time the involvement of the circadian clock in the host response following Giardia infection.

The Giardia lamblia genome.

PubMed

Adam, R D

2000-04-10

Giardia lamblia is a protozoan parasite of humans and other mammals that is thought to be one of the most primitive extant eukaryotic organisms. Although distinctly eukaryotic, it is notable for its lack of mitochondria, nucleoli, and perixosomes. It has been suggested that Giardia spp. are pre-mitochondriate organisms, but the identification of genes in G. lamblia thought to be of mitochondrial origin has generated controversy regarding that designation. Giardi lamblia trophozoites have two nuclei that are identical in all ways that have been studied. They are polyploid with at least four, and perhaps eight or more, copies of each of five chromosomes per organism and have an estimated genome complexity of 1.2x10(7)bp of DNA, and GC content of 46%. There is evidence for recombination at the telomeres of some of the chromosomes, and multiple size variants of single chromosomes have been identified within cloned isolates. However, the internal regions of the chromosomes demonstrate no evidence of recombination. For example, there is no evidence for control of vsp gene expression by DNA recombination, and no evidence for rapid mutation in the vsp genes. Single pass sequences of approximately 9% of the G. lamblia genome have already been obtained. An ongoing genome project plans to obtain approximately 95% of the genome by a random approach, as well as a complete physical map using a bacterial artificial chromosome library. The results will facilitate a better understanding of the biology of Giardia spp. as well as their phylogenetic relationship to other primitive organisms.

Evaluation of the Roche LightMix Gastro parasites multiplex PCR assay detecting Giardia duodenalis, Entamoeba histolytica, cryptosporidia, Dientamoeba fragilis, and Blastocystis hominis.

PubMed

Friesen, J; Fuhrmann, J; Kietzmann, H; Tannich, E; Müller, M; Ignatius, R

2018-03-23

Multiplex PCR assays offer highly sensitive and specific tools for the detection of enteric pathogens. This prospective study aimed at comparing the novel Roche LightMix Modular Assay Gastro Parasites (LMAGP) detecting Giardia duodenalis, Entamoeba histolytica, Cryptosporidium spp., Blastocystishominis, and Dientamoebafragilis with routine laboratory procedures. Stool specimens (n = 1062 from 1009 patients) were consecutively examined by LMAGP, R-Biopharm Ridascreen enzyme immunoassays (EIAs) detecting G. duodenalis or E. histolytica/dispar, and microscopy of wet mounts. Discrepant results were analysed by in-house PCR. D. fragilis or B. hominis were detected by LMAGP in 131 (14.4%) and 179 (19.9%; 16 samples positive by microscopy; p < 0.0001) of 909 samples, respectively. Of 918 samples analysed for Cryptosporidium spp., six were positive by LMAGP (three could be confirmed by Kinyoun staining and one by in-house PCR). G. duodenalis was detected by LMAGP, EIA, or microscopy in 20, 16, or 9 of 1039 stool samples, respectively; all four samples missed by EIA were confirmed by in-house PCR. In total, 938 stool samples were analysed for E. histolytica/dispar. Nine of ten EIA-positive samples were negative by LMAGP but positive by in-house PCR for E. dispar. One E. histolytica infection (positive by both LMAGP and in-house PCR) was missed by EIA and microscopy. Parasites only detected by microscopy included Enterobius vermicularis eggs (n = 3) and apathogenic amoebae (n = 27). The data call for routine use of multiplex PCR assays for the detection of enteric protozoan parasites in laboratory diagnostics. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Beaver Fever: Whole-Genome Characterization of Waterborne Outbreak and Sporadic Isolates To Study the Zoonotic Transmission of Giardiasis.

PubMed

Tsui, Clement K-M; Miller, Ruth; Uyaguari-Diaz, Miguel; Tang, Patrick; Chauve, Cedric; Hsiao, William; Isaac-Renton, Judith; Prystajecky, Natalie

2018-04-25

Giardia causes the diarrheal disease known as giardiasis; transmission through contaminated surface water is common. The protozoan parasite's genetic diversity has major implications for human health and epidemiology. To determine the extent of transmission from wildlife through surface water, we performed whole-genome sequencing (WGS) to characterize 89 Giardia duodenalis isolates from both outbreak and sporadic infections: 29 isolates from raw surface water, 38 from humans, and 22 from veterinary sources. Using single nucleotide variants (SNVs), combined with epidemiological data, relationships contributing to zoonotic transmission were described. Two assemblages, A and B, were identified in surface water, human, and veterinary isolates. Mixes of zoonotic assemblages A and B were seen in all the community waterborne outbreaks in British Columbia (BC), Canada, studied. Assemblage A was further subdivided into assemblages A1 and A2 based on the genetic variation observed. The A1 assemblage was highly clonal; isolates of surface water, human, and veterinary origins from Canada, United States, and New Zealand clustered together with minor variation, consistent with this being a panglobal zoonotic lineage. In contrast, assemblage B isolates were variable and consisted of several clonal lineages relating to waterborne outbreaks and geographic locations. Most human infection isolates in waterborne outbreaks clustered with isolates from surface water and beavers implicated to be outbreak sources by public health. In-depth outbreak analysis demonstrated that beavers can act as amplification hosts for human infections and can act as sources of surface water contamination. It is also known that other wild and domesticated animals, as well as humans, can be sources of waterborne giardiasis. This study demonstrates the utility of WGS in furthering our understanding of Giardia transmission dynamics at the water-human-animal interface. IMPORTANCE Giardia duodenalis causes large numbers of gastrointestinal illness in humans. Its transmission through the contaminated surface water/wildlife intersect is significant, and the water-dwelling rodents beavers have been implicated as one important reservoir. To trace human infections to their source, we used genome techniques to characterize genetic relationships among 89 Giardia isolates from surface water, humans, and animals. Our study showed the presence of two previously described genetic assemblages, A and B, with mixed infections detected from isolates collected during outbreaks. Study findings also showed that while assemblage A could be divided into A1 and A2, A1 showed little genetic variation among animal and human hosts in isolates collected from across the globe. Assemblage B, the most common type found in the study surface water samples, was shown to be highly variable. Our study demonstrates that the beaver is a possible source of human infections from contaminated surface water, while acknowledging that theirs is only one role in the complex cycle of zoonotic spread. Mixes of parasite groups have been detected in waterborne outbreaks. More information on Giardia diversity and its evolution using genomics will further the understanding of the epidemiology of spread of this disease-causing protozoan. © Crown copyright 2018.

Presence of Cryptosporidium parvum and Giardia lamblia in water samples from Southeast Asia: towards an integrated water detection system.

PubMed

Kumar, Thulasi; Abd Majid, Mohamad Azlan; Onichandran, Subashini; Jaturas, Narong; Andiappan, Hemah; Salibay, Cristina C; Tabo, Hazel A L; Tabo, Norbel; Dungca, Julieta Z; Tangpong, Jitbanjong; Phiriyasamith, Sucheep; Yuttayong, Boonyaorn; Polseela, Raxsina; Do, Binh Nhu; Sawangjaroen, Nongyao; Tan, Tian-Chye; Lim, Yvonne A L; Nissapatorn, Veeranoot

2016-01-13

Access to clean and safe drinking water that is free from pathogenic protozoan parasites, especially Cryptosporidium parvum and Giardia lamblia that cause gastrointestinal illness in humans, is still an issue in Southeast Asia (SEA). This study is the first attempt to detect the aforementioned protozoan parasites in water samples from countries in SEA, using real-time polymerase chain reaction (qPCR) assays. A total of 221 water samples of 10 l each were collected between April and October 2013 from Malaysia (53), Thailand (120), the Philippines (33), and Vietnam (15). A physicochemical analysis was conducted. The water samples were processed in accordance with the US Environmental Protection Agency's methods 1622/1623.1, microscopically observed and subsequently screened using qPCR assays. Cryptosporidium oocysts were detected in treated water samples from the Philippines (1/10), with a concentration of 0.06 ± 0.19 oocyst/L, and untreated water samples from Thailand (25/93), Malaysia (17/44), and the Philippines (11/23), with concentrations ranging from 0.13 ± 0.18 to 0.57 ± 1.41 oocyst/L. Giardia cysts were found in treated water samples from the Philippines (1/10), with a concentration of 0.02 ± 0.06 cyst/L, and in untreated water samples from Thailand (20/93), Vietnam (5/10), Malaysia (22/44), and the Philippines (16/23), with concentrations ranging from 0.12 ± 0.3 to 8.90 ± 19.65 cyst/L. The pathogens C. parvum and G. lamblia were detected using using qPCR assays by targeting the 138-bp fragment and the small subunit gene, respectively. C. parvum was detected in untreated water samples from the Philippines (1/23) and Malaysia (2/44), whilst, G. lamblia detected was detected in treated water samples from the Philippines (1/10) and in untreated water samples from Thailand (21/93), Malaysia (12/44), and the Philippines (17/23). Nitrate concentration was found to have a high positive correlation with (oo)cyst (0.993). The presence of (oo)cysts in the water samples means that there is potential risk for zoonotic disease transmission in the studied countries. Detection using qPCR is feasible for quantifying both pathogenic C. parvum and G. lamblia in large water samples.

Foodborne intestinal protozoan infection and associated factors among patients with watery diarrhea in Northern Ethiopia; a cross-sectional study.

PubMed

Berhe, Birhane; Bugssa, Gessessew; Bayisa, Sena; Alemu, Megbaru

2018-03-02

Intestinal protozoa are parasites transmitted by consumption of contaminated water and food and mainly affect children and elder people and cause considerable health problems. They are the leading causes of outpatient morbidity due to diarrhea in the developing countries. So, assessing water and food source of diarrheal patients and identifying the main associated factors for transmission of protozoan parasitic infections help for effective control measures of protozoan infections. Hence, the current study was aimed at determining the prevalence of foodborne intestinal protozoa infections and associated factors among diarrheic patients in North Ethiopia. A health facility based cross-sectional study was conducted among 223 patients with watery diarrhea in four selected government health facilities in North Ethiopia from November 2016-June 2017. A structured questionnaire was used to collect data on socio-demography of study participants and factors associated with foodborne protozoa infections. The diarrheic stool samples were collected, transported, and processed using direct wet mount, formal-ether concentration and modified ZiehlNeelson staining methods. The data were analyzed using SPSS version 21 and descriptive statistics, bi-variate, and multivariate logistic regressions were computed. P-value < 0.05 at 95% confidence interval was considered statistically significant. The overall prevalence of foodborne protozoa infection was 101 (45.3%). The predominant protozoa species identified was Entamoeba histolytica/dispar 55 (24.7%), followed by Giardia intestinalis 25 (11.2%) and Cryptosporidium species 5 (2.2%). The highest proportion of protozoa infection was observed among males (23.3%) and the age group 15-24 years (13.5%). Statistically significant associations were observed between foodborne protozoan infection and not using any type of recipe to decontaminate salads and fruits (AOR = 2.64, 95 CI: 1.34-5.19, P = 0.005) and using vinegar as a decontaminant (AOR = 2.83, 95 CI: 1.24-6.48, P = 0.014). Eating out (meals at a restaurant) on the other hand was found to be protective for foodborne protozoan infection (AOR = 0.43, 95 CI: 0.23-0.78, P = 0.006). Our study revealed that foodborne protozoa infections are of public health significance in the study area. Vinegar, which is frequently used as a recipe for decontaminating salads and fruits, is inversely related to foodborne protozoa parasite infection .

INVESTIGATION AND EVALUATION OF CRYPTOSPORIDIUM AND GIARDIA IN COMBINED SEWER OVERFLOW (CSO) AND STORMWATER RUNOFF

EPA Science Inventory

Since the first identified Cryptosporidium outbreaks occurred in the 1980s and the massive 1993 Milwaukee, WI outbreak affected more than 400,000 people, the concern over the public health risks related to protozoan pathogens Cryptosporidium and Giardia has g...

Drug-Free Approach To Study the Unusual Cell Cycle of Giardia intestinalis

PubMed Central

Horlock-Roberts, Kathleen; Reaume, Chase; Dayer, Guillem; Ouellet, Christine; Cook, Nicholas

2017-01-01

ABSTRACT Giardia intestinalis is a protozoan parasite that causes giardiasis, a form of severe and infectious diarrhea. Despite the importance of the cell cycle in the control of proliferation and differentiation during a giardia infection, it has been difficult to study this process due to the absence of a synchronization procedure that would not induce cellular damage resulting in artifacts. We utilized counterflow centrifugal elutriation (CCE), a size-based separation technique, to successfully obtain fractions of giardia cultures enriched in G1, S, and G2. Unlike drug-induced synchronization of giardia cultures, CCE did not induce double-stranded DNA damage or endoreplication. We observed increases in the appearance and size of the median body in the cells from elutriation fractions corresponding to the progression of the cell cycle from early G1 to late G2. Consequently, CCE could be used to examine the dynamics of the median body and other structures and organelles in the giardia cell cycle. For the cell cycle gene expression studies, the actin-related gene was identified by the program geNorm as the most suitable normalizer for reverse transcription-quantitative PCR (RT-qPCR) analysis of the CCE samples. Ten of 11 suspected cell cycle-regulated genes in the CCE fractions have expression profiles in giardia that resemble those of higher eukaryotes. However, the RNA levels of these genes during the cell cycle differ less than 4-fold to 5-fold, which might indicate that large changes in gene expression are not required by giardia to regulate the cell cycle. IMPORTANCE Giardias are among the most commonly reported intestinal protozoa in the world, with infections seen in humans and over 40 species of animals. The life cycle of giardia alternates between the motile trophozoite and the infectious cyst. The regulation of the cell cycle controls the proliferation of giardia trophozoites during an active infection and contains the restriction point for the differentiation of trophozoite to cyst. Here, we developed counterflow centrifugal elutriation as a drug-free method to obtain fractions of giardia cultures enriched in cells from the G1, S, and G2 stages of the cell cycle. Analysis of these fractions showed that the cells do not show side effects associated with the drugs used for synchronization of giardia cultures. Therefore, counterflow centrifugal elutriation would advance studies on key regulatory events during the giardia cell cycle and identify potential drug targets to block giardia proliferation and transmission. PMID:28959734

Giardiasis in NSW: Identification of Giardia duodenalis assemblages contributing to human and cattle cases, and an epidemiological assessment of sporadic human giardiasis.

PubMed

Asher, A J; Hose, G; Power, M L

2016-10-01

Two genetic assemblages (A and B) of the protozoan parasite species, Giardia duodenalis, infect humans, domestic animals and wildlife. In New South Wales, Australia, over 2000 sporadic human giardiasis cases are reported annually, but parasite sources and links between sporadic cases are unknown. This study describes G. duodenalis assemblages contributing to human and cattle cases in NSW, and examines demographic, spatial, and temporal distributions of NSW human infections and G. duodenalis assemblages. Genotyping by PCR-restriction fragment length polymorphism of the glutamate dehydrogenase (gdh) gene identified G. duodenalis assemblage B as the most common (86%) cause of infection among human cases (n=165). Approximately 37% of cattle DNA samples were PCR positive (18S rRNA, gdh), and G. duodenalis assemblages E (69%) or B (31%) were identified from these samples. Human assemblage A was more common among older age groups, and seasonality in the geographic dispersal of human assemblage A was observed. The results of this study indicate G. duodenalis assemblage B is highly prevalent among humans in NSW, and the potential for cross-species transmission exists between humans and cattle in this region. Spatio-temporal and demographic distributions of human assemblage A and B are highlighted, and risk factors associated with these dispersal patterns warrants further research. Copyright © 2016 Elsevier B.V. All rights reserved.

FLOTAC for diagnosis of endo-parasites in pet squirrels in southern Italy.

PubMed

d'Ovidio, D; Rinaldi, L; Ianniello, D; Donnelly, T M; Pepe, P; Capasso, M; Cringoli, G

2014-02-24

The present study investigated the occurrence of endoparasites in pet squirrels in southern Italy. Fresh fecal samples were collected from 50 asymptomatic pet squirrels belonging to five different species (Callosciurus finlaysonii, n=6, C. prevosti, n=6; Tamias striatus, n=26, T. sibiricus, n=10; Sciurus carolinensis, n=2) housed both in pet shops and/or in private residences. All fecal samples were processed using the FLOTAC pellet technique to identify and count helminth eggs/larvae and protozoan cysts/oocysts. In addition, to detect Cryptosporidium spp. and Giardia spp. the samples were analyzed by the Remel Xpect(®) immunoassay. Helminth eggs were detected in 9 out of 50 squirrels. Specifically, eggs of Dicrocoelium dendriticum were found in 5 squirrels (C. finlaysonii, n=2; C. prevosti, n=2; T. striatus, n=1); eggs of the pinworm Syphacia spp. in 3 squirrels (C. prevosti, n=2; T. striatus, n=1); and eggs of gastrointestinal nematoda (Nippostrongylus-like) were found in 1 subject (C. prevosti). Finally, two squirrels (C. prevosti) had multiple parasitic infections with D. dendriticum and Capillaria hepatica, and with D. dendriticum and Strongyloides spp., respectively. None of the samples were positive for Cryptosporidium spp. or Giardia spp. or any other protozoa (e.g. Eimeria). To the authors' knowledge, this is the first report of a D. dendriticum natural infection in pet rodents. Copyright © 2013 Elsevier B.V. All rights reserved.

Molecular epidemiology of Giardia duodenalis in an endangered carnivore--the African painted dog.

PubMed

Ash, A; Lymbery, A; Lemon, J; Vitali, S; Thompson, R C A

2010-12-15

The African painted dog (Lycaon pictus) is an endangered carnivore of sub-Saharan Africa. To assist in conservation efforts a parasitological survey was conducted on wild and captive populations. Faecal samples were collected and examined for the presence of parasites using traditional microscopy techniques. The protozoan Giardia duodenalis was identified at a prevalence of approximately 26% in the wild populations and 62% in the captive population. Molecular characterisation of these isolates using three loci, 18S rRNA, β-giardin and the glutamate dehydrogenase gene revealed the zoonotic assemblages A and B existed in high proportions in both populations. The dog assemblages C and D were rarely observed. The identification of the zoonotic genotype suggests this species has the potential to act as a reservoir for human infections. Zoonotic transmission may be possible in captive populations due to the close interaction with humans however, in wild populations anthropozoonotic transmission seems more likely. This study is the first to observe G. duodenalis in the African painted dog and to identify a possible emerging disease in this wild carnivore. Copyright © 2010 Elsevier B.V. All rights reserved.

Both endo-siRNAs and tRNA-derived small RNAs are involved in the differentiation of primitive eukaryote Giardia lamblia

PubMed Central

Liao, Jian-You; Guo, Yan-Hua; Zheng, Ling-Ling; Li, Yan; Xu, Wen-Li; Zhang, Yu-Chan; Zhou, Hui; Lun, Zhao-Rong; Ayala, Francisco J.; Qu, Liang-Hu

2014-01-01

Small RNAs (sRNAs), including microRNAs and endogenous siRNAs (endo-siRNAs), regulate most important biologic processes in eukaryotes, such as cell division and differentiation. Although sRNAs have been extensively studied in various eukaryotes, the role of sRNAs in the early emergence of eukaryotes is unclear. To address these questions, we deep sequenced the sRNA transcriptome of four different stages in the differentiation of Giardia lamblia, one of the most primitive eukaryotes. We identified a large number of endo-siRNAs in this fascinating parasitic protozoan and found that they were produced from live telomeric retrotransposons and three genomic regions (i.e., endo-siRNA generating regions [eSGRs]). eSGR-derived endo-siRNAs were proven to target mRNAs in trans. Gradual up-regulation of endo-siRNAs in the differentiation of Giardia suggested that they might be involved in the regulation of this process. This hypothesis was supported by the impairment of the differentiation ability of Giardia when GLDICER, essential for the biogenesis of endo-siRNAs, was knocked down. Endo-siRNAs are not the only sRNA regulators in Giardia differentiation, because a great number of tRNAs-derived sRNAs showed more dramatic expression changes than endo-siRNAs in this process. We totally identified five novel kinds of tRNAs-derived sRNAs and found that the biogenesis in four of them might be correlated with that of stress-induced tRNA-derived RNA (sitRNA), which was discovered in our previous studies. Our studies reveal an unexpected complex panorama of sRNA in G. lamblia and shed light on the origin and functional evolution of eukaryotic sRNAs. PMID:25225396

Modeling Long-Term Host Cell-Giardia lamblia Interactions in an In Vitro Co-Culture System

PubMed Central

Fisher, Bridget S.; Estraño, Carlos E.; Cole, Judith A.

2013-01-01

Globally, there are greater than 700,000 deaths per year associated with diarrheal disease. The flagellated intestinal parasite, Giardia lamblia, is one of the most common intestinal pathogens in both humans and animals throughout the world. While attached to the gastrointestinal epithelium, Giardia induces epithelial cell apoptosis, disrupts tight junctions, and increases intestinal permeability. The underlying cellular and molecular mechanisms of giardiasis, including the role lamina propria immune cells, such as macrophages, play in parasite control or clearance are poorly understood. Thus far, one of the major obstacles in ascertaining the mechanisms of Giardia pathology is the lack of a functionally relevant model for the long-term study of the parasite in vitro. Here we report on the development of an in vitro co-culture model which maintains the basolateral-apical architecture of the small intestine and allows for long-term survival of the parasite. Using transwell inserts, Caco-2 intestinal epithelial cells and IC-21 macrophages are co-cultured in the presence of Giardia trophozoites. Using the developed model, we show that Giardia trophozoites survive over 21 days and proliferate in a combination media of Caco-2 cell and Giardia medium. Giardia induces apoptosis of epithelial cells through caspase-3 activation and macrophages do not abrogate this response. Additionally, macrophages induce Caco-2 cells to secrete the pro-inflammatory cytokines, GRO and IL-8, a response abolished by Giardia indicating parasite induced suppression of the host immune response. The co-culture model provides additional complexity and information when compared to a single-cell model. This model will be a valuable tool for answering long-standing questions on host-parasite biology that may lead to discovery of new therapeutic interventions. PMID:24312526

A Comparative Study of the Common Protozoan Parasites of Clarias gariepinus from the Wild and Cultured Environments in Benue State, Nigeria

PubMed Central

Omeji, S.; Solomon, S. G.; Idoga, E. S.

2011-01-01

A total of one hundred and twenty Clarias gariepinus comprising 30 dead and 30 live fishes were examined for protozoan parasites infestation, sixty each from the wild and a pond (cultured environment) over a period of six months. Ichthyophthirius multifiliis was the most common protozoan parasites found in C. gariepinus from the wild (River Benue) and cultured (pond) environments. These protozoan parasites constitute 37.08% of the total parasites encountered for fishes in the pond and 42.51% of fishes in the wild. Among the body parts of the sampled fishes from the pond, the gills had the highest parasite load (38.86%). Also, the gills had the highest parasite load (40.54%) among the body parts of the fishes sampled from the wild. Fishes not infested with any protozoan parasites from the pond constituted 36.70% of the total fish sampled. On the other hand, fishes not infested with any protozoan parasites from the wild constituted 31.65% of the total fish sampled. Female fishes had more protozoan parasites than the male fishes. Bigger fishes of total length (25–48 cm) had more parasite load than the smaller ones (19–24 cm). Also, fishes between 150–750 g had more parasite load than the smaller ones of less than 150 g. Protozoan parasite load of fish from the cultured environment (pond) did not differ significantly (P < 0.05) from those from River Benue (wild). PMID:22028952

High occurrence of Blastocystis sp. subtypes 1-3 and Giardia intestinalis assemblage B among patients in Zanzibar, Tanzania.

PubMed

Forsell, Joakim; Granlund, Margareta; Samuelsson, Linn; Koskiniemi, Satu; Edebro, Helén; Evengård, Birgitta

2016-06-29

Blastocystis is a common intestinal parasite with worldwide distribution but the distribution of Blastocystis and its subtypes in East Africa is largely unknown. In this study, we investigate the distribution of Blastocystis subtypes in Zanzibar, Tanzania and report the prevalence of intestinal parasites using both molecular methods and microscopy. Stool samples were collected from both diarrhoeic and non-diarrhoeic outpatients in Zanzibar. In addition to microscopy, real-time PCR for Blastocystis, Entamoeba histolytica and E. dispar, Giardia intestinalis, Cryptosporidium spp., and Dientamoeba fragilis was used. Blastocystis subtypes were determined by a conventional PCR followed by partial sequencing of the SSU-rRNA gene. Genetic assemblages of Giardia were determined by PCR with assemblage specific primers. Intestinal parasites were detected in 85 % of the 174 participants, with two or more parasites present in 56 %. Blastocystis sp. and Giardia intestinalis were the most common parasites, identified by PCR in 61 and 53 % of the stool samples respectively, but no correlation between carriage of Blastocystis and Giardia was found. The Blastocystis subtype distribution was ST1 34.0 %, ST2 26.4 %, ST3 25.5 %, ST7 0.9 %, and 13.2 % were positive only by qPCR (non-typable). The Giardia genetic assemblages identified were A 6.5 %, B 85 %, A + B 4.3 %, and non-typable 4.3 %. The detection rate with microscopy was substantially lower than with PCR, 20 % for Blastocystis and 13.8 % for Giardia. The prevalence of Blastocystis increased significantly with age while Giardia was most prevalent in children two to five years old. No correlation between diarrhoea and the identification of Giardia, Blastocystis, or their respective genetic subtypes could be shown and, as a possible indication of parasite load, the mean cycle threshold values in the qPCR for Giardia were equal in diarrhoeic and non-diarrhoeic patients. Carriage of intestinal parasites was very common in the studied population in Zanzibar. The most commonly detected parasites, Blastocystis and Giardia, had different age distributions, possibly indicating differences in transmission routes, immunity, and/or other host factors for these two species. In the Blastocystis subtype analysis ST1-3 were common, but ST4, a subtype quite common in Europe, was completely absent, corroborating the geographical differences in subtype distributions previously reported.

Giardia Colonizes and Encysts in High-Density Foci in the Murine Small Intestine

PubMed Central

Barash, N. R.; Nosala, C.; Pham, J. K.; McInally, S. G.; Gourguechon, S.; McCarthy-Sinclair, B.

2017-01-01

ABSTRACT Giardia lamblia is a highly prevalent yet understudied protistan parasite causing significant diarrheal disease worldwide. Hosts ingest Giardia cysts from contaminated sources. In the gastrointestinal tract, cysts excyst to become motile trophozoites, colonizing and attaching to the gut epithelium. Trophozoites later differentiate into infectious cysts that are excreted and contaminate the environment. Due to the limited accessibility of the gut, the temporospatial dynamics of giardiasis in the host are largely inferred from laboratory culture and thus may not mirror Giardia physiology in the host. Here, we have developed bioluminescent imaging (BLI) to directly interrogate and quantify the in vivo temporospatial dynamics of Giardia infection, thereby providing an improved murine model to evaluate anti-Giardia drugs. Using BLI, we determined that parasites primarily colonize the proximal small intestine nonuniformly in high-density foci. By imaging encystation-specific bioreporters, we show that encystation initiates shortly after inoculation and continues throughout the duration of infection. Encystation also initiates in high-density foci in the proximal small intestine, and high density contributes to the initiation of encystation in laboratory culture. We suggest that these high-density in vivo foci of colonizing and encysting Giardia likely result in localized disruption to the epithelium. This more accurate visualization of giardiasis redefines the dynamics of the in vivo Giardia life cycle, paving the way for future mechanistic studies of density-dependent parasitic processes in the host. IMPORTANCE Giardia is a single-celled parasite causing significant diarrheal disease in several hundred million people worldwide. Due to limited access to the site of infection in the gastrointestinal tract, our understanding of the dynamics of Giardia infections in the host has remained limited and largely inferred from laboratory culture. To better understand Giardia physiology and colonization in the host, we developed imaging methods to quantify Giardia expressing bioluminescent physiological reporters in two relevant animal models. We discovered that parasites primarily colonize and encyst in the proximal small intestine in discrete, high-density foci. We also show that high parasite density contributes to encystation initiation. PMID:28656177

Antiprotozoal activities of benzimidazoles and correlations with beta-tubulin sequence.

PubMed Central

Katiyar, S K; Gordon, V R; McLaughlin, G L; Edlind, T D

1994-01-01

Benzimidazoles have been widely used since the 1960s as anthelmintic agents in veterinary and human medicine and as antifungal agents in agriculture. More recently, selected benzimidazole derivatives were shown to be active in vitro against two protozoan parasites, Trichomonas vaginalis and Giardia lamblia, and clinical studies with AIDS patients have suggested that microsporidia are susceptible as well. Here, we first present in vitro susceptibility data for T. vaginalis and G. lamblia using an expanded set of benzimidazole derivatives. Both parasites were highly susceptible to four derivatives, including mebendazole, flubendazole, and fenbendazole (50% inhibitory concentrations of 0.005 to 0.16 microgram/ml). These derivatives also had lethal activity that was time dependent: 90% of T. vaginalis cells failed to recover following a 20-h exposure to mebendazole at 0.17 microgram/ml. G. lamblia, but not T. vaginalis, was highly susceptible to five additional derivatives. Next, we examined in vitro activity of benzimidazoles against additional protozoan parasites: little or no activity was observed against Entamoeba histolytica, Leishmania major, and Acanthamoeba polyphaga. Since the microtubule protein beta-tubulin has been identified as the benzimidazole target in helminths and fungi, potential correlations between benzimidazole activity and beta-tubulin sequence were examined. This analysis included partial sequences (residues 108 to 259) from the organisms mentioned above, as well as the microsporidia Encephalitozoon hellem and Encephalitozoon cuniculi and the sporozoan Cryptosporidium parvum. beta-tubulin residues Glu-198 and, in particular, Phe-200 are strong predictors of benzimidazole susceptibility; both are present in Encephalitozoon spp. but absent in C. parvum. PMID:7811023

Protozoa as a cause of recurrent abdominal pain in children.

PubMed

Gijsbers, Carolien F M; Schweizer, Joachim J; Büller, Hans A

2013-11-01

The aim of this study was to investigate whether protozoa can be identified as a cause of recurrent abdominal pain (RAP), and whether protozoan infections can be recognized by a specific clinical presentation. For 2 years, all patients (ages 4-16 years) fulfilling the Apley criteria of RAP referred to secondary care were prospectively evaluated for protozoa (Giardia lamblia, Dientamoeba fragilis, Blastocystis hominis) and treated if positive. Re-examination followed at least 10 days after treatment. Disappearance of pain with eradication and a pain-free follow-up of at least 6 months were considered to be indicative of a causal relation with RAP. The predictive value of the characteristics of the pain for protozoan infections was calculated. Of 220 included patients (92 boys, mean age 8.8 years), 215 brought a stool sample; 73 (34%) carried parasites, 10 of whom had 2 parasites, 2 had 3 parasites. Sixty-five patients were treated. Twenty-five (11%) were pain-free after eradication (21 had D fragilis, 8 B hominis, 4 G lamblia), of whom 11 had another infection (2) or constipation (9) as second diagnosis for the pain. Five had recurrence of infection with D fragilis and were again pain-free with eradication. Patients with protozoa as cause of their pain did not show differences with respect to their presentation when compared with patients with an asymptomatic infection and patients without protozoa. Protozoa were found as the cause of pain in 6% to 11% of children with RAP. These patients did not show a characteristic presentation when compared with patients with other causes of abdominal pain.

Prevalence of intestinal parasites among school children in northern districts of West Bank-Palestine.

PubMed

Hussein, Ayman S

2011-02-01

To assess the prevalence of intestinal parasite infections in northern districts of West Bank, Palestine and to determine associated sociodemographic factors. Random sampling of schoolchildren from rural and urban areas was carried out. Participants provided faecal samples and answered a questionnaire about their demographics and hygiene habits. Faecal samples underwent microscopy and PCR to screen for protozoan and helminths. Seven hundred and thirty-five samples were collected from children aged 9.5 years on average. The overall prevalence of parasitic infection was 22.2%. The rates of infections with amoeba, Giardia intestinalis, Entrobius vermicularis and Ascaris lumbricoides were 9.7%, 4.1%, 1.6% and 3.8%, respectively. Real-time PCR was performed to differentiate between Entamoeba histolytica and Entamoeba dispar. Results showed that 14% of samples positive with microscopy for amoeba were positive for E. histolytica. There was no significant association between sex and rates of infections (P-value > 0.05). There were, however, significant association between parasite infections and parents' education, place of residence, washing hands habits (P-value > 0.05). No significant association was found with number of family members or eating in school canteens (P-value > 0.05). Intestinal parasite infections are endemic in West Bank. Interventions such as health education and sanitation are needed. © 2010 Blackwell Publishing Ltd.

DNA Extraction from Protozoan Oocysts/Cysts in Feces for Diagnostic PCR

PubMed Central

2014-01-01

PCR detection of intestinal protozoa is often restrained by a poor DNA recovery or by inhibitors present in feces. The need for an extraction protocol that can overcome these obstacles is therefore clear. QIAamp® DNA Stool Mini Kit (Qiagen) was evaluated for its ability to recover DNA from oocysts/cysts directly from feces. Twenty-five Giardia-positive, 15 Cryptosporidium-positive, 15 Entamoeba histolytica-positive, and 45 protozoa-free samples were processed as control by microscopy and immunoassay tests. DNA extracts were amplified using 3 sets of published primers. Following the manufacturer's protocol, the kit showed sensitivity and specificity of 100% towards Giardia and Entamoeba. However, for Cryptosporidium, the sensitivity and specificity were 60% (9/15) and 100%, respectively. A series of optimization experiments involving various steps of the kit's protocol were conducted using Cryptosporidium-positive samples. The best DNA recoveries were gained by raising the lysis temperature to the boiling point for 10 min and the incubation time of the InhibitEX tablet to 5 min. Also, using a pre-cooled ethanol for nucleic acid precipitation and small elution volume (50-100 µl) were valuable. The sensitivity of the amended protocol to Cryptosporidium was raised to 100%. Cryptosporidium DNA was successfully amplified by either the first or the second primer set. When applied on parasite-free feces spiked with variable oocysts/cysts counts, ≈ 2 oocysts/cysts were theoretically enough for detection by PCR. To conclude, the Qiagen kit with the amended protocol was proved to be suitable for protozoan DNA extraction directly from feces and support PCR diagnosis. PMID:25031466

DNA extraction from protozoan oocysts/cysts in feces for diagnostic PCR.

PubMed

Hawash, Yousry

2014-06-01

PCR detection of intestinal protozoa is often restrained by a poor DNA recovery or by inhibitors present in feces. The need for an extraction protocol that can overcome these obstacles is therefore clear. QIAamp® DNA Stool Mini Kit (Qiagen) was evaluated for its ability to recover DNA from oocysts/cysts directly from feces. Twenty-five Giardia-positive, 15 Cryptosporidium-positive, 15 Entamoeba histolytica-positive, and 45 protozoa-free samples were processed as control by microscopy and immunoassay tests. DNA extracts were amplified using 3 sets of published primers. Following the manufacturer's protocol, the kit showed sensitivity and specificity of 100% towards Giardia and Entamoeba. However, for Cryptosporidium, the sensitivity and specificity were 60% (9/15) and 100%, respectively. A series of optimization experiments involving various steps of the kit's protocol were conducted using Cryptosporidium-positive samples. The best DNA recoveries were gained by raising the lysis temperature to the boiling point for 10 min and the incubation time of the InhibitEX tablet to 5 min. Also, using a pre-cooled ethanol for nucleic acid precipitation and small elution volume (50-100 µl) were valuable. The sensitivity of the amended protocol to Cryptosporidium was raised to 100%. Cryptosporidium DNA was successfully amplified by either the first or the second primer set. When applied on parasite-free feces spiked with variable oocysts/cysts counts, ≈ 2 oocysts/cysts were theoretically enough for detection by PCR. To conclude, the Qiagen kit with the amended protocol was proved to be suitable for protozoan DNA extraction directly from feces and support PCR diagnosis.

Performance of Glutamate Dehydrogenase and Triose Phosphate Isomerase Genes in the Analysis of Genotypic Variability of Isolates of Giardia duodenalis from Livestocks

PubMed Central

Fava, Natália M. N.; Soares, Rodrigo M.; Scalia, Luana A. M.; Kalapothakis, Evanguedes; Pena, Isabella F.; Vieira, Carlos U.; Faria, Elaine S. M.; Cunha, Maria J.; Couto, Talles R.; Cury, Márcia Cristina

2013-01-01

Giardia duodenalis is a small intestinal protozoan parasite of several terrestrial vertebrates. This work aims to assess the genotypic variability of Giardia duodenalis isolates from cattle, sheep and pigs in the Southeast of Brazil, by comparing the standard characterization between glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) primers. Fecal samples from the three groups of animals were analyzed using the zinc sulphate centrifugal flotation technique. Out of 59 positive samples, 30 were from cattle, 26 from sheep and 3 from pigs. Cyst pellets were stored and submitted to PCR and nested-PCR reactions with gdh and tpi primers. Fragment amplification of gdh and tpi genes was observed in 25 (42.4%) and 36 (61.0%) samples, respectively. Regarding the sequencing, 24 sequences were obtained with gdh and 20 with tpi. For both genes, there was a prevalence of E specific species assemblage, although some isolates have been identified as A and B, by the tpi sequencing. This has also shown a larger number of heterogeneous sequences, which have been attribute to mixed infections between assemblages B and E. The largest variability of inter-assemblage associated to the frequency of heterogeneity provided by tpi sequencing reinforces the polymorphic nature of this gene and makes it an excellent target for studies on molecular epidemiology. PMID:24308010

A novel high-resolution multilocus sequence typing of Giardia intestinalis Assemblage A isolates reveals zoonotic transmission, clonal outbreaks and recombination.

PubMed

Ankarklev, Johan; Lebbad, Marianne; Einarsson, Elin; Franzén, Oscar; Ahola, Harri; Troell, Karin; Svärd, Staffan G

2018-06-01

Molecular epidemiology and genotyping studies of the parasitic protozoan Giardia intestinalis have proven difficult due to multiple factors, such as low discriminatory power in the commonly used genotyping loci, which has hampered molecular analyses of outbreak sources, zoonotic transmission and virulence types. Here we have focused on assemblage A Giardia and developed a high-resolution assemblage-specific multilocus sequence typing (MLST) method. Analyses of sequenced G. intestinalis assemblage A genomes from different sub-assemblages identified a set of six genetic loci with high genetic variability. DNA samples from both humans (n = 44) and animals (n = 18) that harbored Giardia assemblage A infections, were PCR amplified (557-700 bp products) and sequenced at the six novel genetic loci. Bioinformatic analyses showed five to ten-fold higher levels of polymorphic sites than what was previously found among assemblage A samples using the classic genotyping loci. Phylogenetically, a division of two major clusters in assemblage A became apparent, separating samples of human and animal origin. A subset of human samples (n = 9) from a documented Giardia outbreak in a Swedish day-care center, showed full complementarity at nine genetic loci (the six new and the standard BG, TPI and GDH loci), strongly suggesting one source of infection. Furthermore, three samples of human origin displayed MLST profiles that were phylogenetically more closely related to MLST profiles from animal derived samples, suggesting zoonotic transmission. These new genotyping loci enabled us to detect events of recombination between different assemblage A isolates but also between assemblage A and E isolates. In summary, we present a novel and expanded MLST strategy with significantly improved sensitivity for molecular analyses of virulence types, zoonotic potential and source tracking for assemblage A Giardia. Copyright © 2018. Published by Elsevier B.V.

Efficacy of nitazoxanide to treat natural Giardia infections in dogs.

PubMed

Moron-Soto, Mario; Gutierrez, Lilia; Sumano, Héctor; Tapia, Graciela; Alcala-Canto, Yazmin

2017-01-31

Giardia parasites cause gastrointestinal disease in humans, dogs, and many other animals worldwide. The treatment of dogs for giardiasis requires further investigation to ascertain levels of drug efficacy and the possibility of adverse side effects. Nitazoxanide (NTZ) has shown good clinical anti-Giardia activity in humans, yet it has not been evaluated for the treatment of giardiasis in dogs. Thirty-five dogs, naturally infected with Giardia were divided into five groups (n = 7): dogs in group NTZ1, NTZ2, and NTZ3 were treated with a single oral dose of 37.5 mg/kg, 75 mg/kg, and 150 mg/kg, respectively, of NTZ on days 0 and 14. The fourth group was treated with a commercially available regimen that includes a combination of pyrantel, praziquantel, and febantel (FEB) administered orally for three consecutive days. Additionally, an untreated control group was established. Giardia cysts from the stool of each dog were quantified on days -3, 0, 5, 7, 9, 11, 14, 18, 25, and 28. Biochemical parameters were evaluated in all dogs, before the first treatment and after concluding the experiment. Shedding of Giardia cysts was reduced in all treated groups when compared to untreated controls (P < 0.01). However, NTZ2, NTZ3, and FEB had a lower risk during the study. Furthermore, NTZ was also effective against another protozoan, Cryptosporidium spp. at doses of 75 mg/kg and 150 mg/kg, in contrast to the combination of febantel + pyrantel + praziquantel. Biochemical parameters of treated animals, namely, aspartate transaminase and alanine transaminase enzymes, remained within physiological ranges. Based on these results, the implementation of NTZ as a treatment for giardiasis in dogs is proposed. The administration of a single dose is an important advantage of NTZ because it reduces workload, particularly in animals placed in shelters and kennels, where handling of large numbers of animals is required, and personnel is frequently scarce.

A Retrospective Analysis of the Results of a Five-Year (2005-2009) Parasitological Examination for Common Intestinal Parasites from Bale-Robe Health Center, Robe Town, Southeastern Ethiopia.

PubMed

Chala, Bayissa

2013-01-01

A cross-sectional retrospective survey using the past five years clinical records (2005-2009) was conducted. The study was aimed at assessing the status of common intestinal parasites from Bale-Robe Health Center, Southeastern Ethiopia, in 2009/2010. The survey involved collection of data recorded on intestinal parasite from the health center during 2005-2009. Precoded questionnaires and interviews were also supplemented for knowledge attitude practices survey (KAPs survey) to assess awareness level of treatment seekers. Analysis of the various associations and strength of significant variations among qualitative and quantitative variables were assessed. The results revealed that Entamoeba histolytica (36.1%) and Giardia lamblia (11.0%), both being protozoan parasites were found to be the most prevalent intestinal parasites encountered during 2005-2009. The least prevalent intestinal parasite recorded was Strongyloides stercoralis (1.1%). Most intestinal parasites were detected among age group of 15 years and above than 0-4 and 5-14 years as shown in Table 4. There was a significant correlation between intestinal parasites prevalence and the age of treatment seeking individuals (P < 0.05). A sharp increasing trend of E. histolytica and Ascaris lumbricoides infections was observed owing to low personal and environmental sanitation of the majority of the society. Initiation of health education at different levels could be recommended to mitigate infectious parasites in the area.

Prevalence of intestinal parasitic infections and associated risk factors among pregnant women attending antenatal care center at Felege Hiwot Referral Hospital, northwest Ethiopia.

PubMed

Derso, Adane; Nibret, Endalkachew; Munshea, Abaineh

2016-09-30

Parasitic infections affect tens of millions of pregnant women worldwide, and directly or indirectly lead to a spectrum of adverse maternal and fetal/placental effects. The objective of this study was to assess the prevalence of intestinal parasite infections and associated risk factors among pregnant women attending antenatal care center in Felege Hiwot Referral Hospital, Bahir Dar city, northwest Ethiopia. A cross-sectional hospital based study was conducted from November 2013 to January 2014 among 384 pregnant women. Stool samples were examined for the presence of trophozoites, cysts, oocysts, and ova using direct, formal-ether sedimentation, and modified Ziehl-Neelsen techniques. An overall prevalence of 31.5 % intestinal parasite infections was recorded. Eight different species of intestinal parasites were found: two protozoan and six helminth species. The highest prevalence was due to Giardia lamblia (13.3 %) followed by Entamoeba histolytica/dispar (7.8 %), hookworm (5.5 %), Ascaris lumbricoides (2.9 %), Schistosoma mansoni (2.9 %), Strongyloides stercoralis (1.6 %), Taenia spp. (0.8 %), and Hymenolepis nana (0.3 %). A relatively high prevalence of intestinal parasite infections was observed among pregnant women. Routine stool examination and provision of health education are required for early medical intervention that would affect the pregnant mothers and their foetuses.

Migrant Workers in Malaysia: Current Implications of Sociodemographic and Environmental Characteristics in the Transmission of Intestinal Parasitic Infections

PubMed Central

Sahimin, Norhidayu; Lim, Yvonne A. L.; Ariffin, Farnaza; Behnke, Jerzy M.; Lewis, John W.

2016-01-01

A cross-sectional study of intestinal parasitic infections amongst migrant workers in Malaysia was conducted. A total of 388 workers were recruited from five sectors including manufacturing, construction, plantation, domestic and food services. The majority were recruited from Indonesia (n = 167, 43.3%), followed by Nepal (n = 81, 20.9%), Bangladesh (n = 70, 18%), India (n = 47, 12.1%) and Myanmar (n = 23, 5.9.2%). A total of four nematode species (Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis and hookworms), one cestode (Hymenolepis nana) and three protozoan species (Entamoeba histolytica/dispar, Giardia sp. and Cryptosporidium spp.) were identified. High prevalence of infections with A. lumbricoides (43.3%) was recorded followed by hookworms (13.1%), E. histolytica/dispar (11.6%), Giardia sp. (10.8%), T. trichura (9.5%), Cryptosporodium spp. (3.1%), H. nana (1.8%) and E. vermicularis (0.5%). Infections were significantly influenced by socio-demographic (nationality), and environmental characteristics (length of working years in the country, employment sector and educational level). Up to 84.0% of migrant workers from Nepal and 83.0% from India were infected with intestinal parasites, with the ascarid nematode A. lumbricoides occurring in 72.8% of the Nepalese and 68.1% of the Indian population. In addition, workers with an employment history of less than a year or newly arrived in Malaysia were most likely to show high levels of infection as prevalence of workers infected with A. lumbricoides was reduced from 58.2% to 35.4% following a year’s residence. These findings suggest that improvement is warranted in public health and should include mandatory medical screening upon entry into the country. PMID:27806046

Migrant Workers in Malaysia: Current Implications of Sociodemographic and Environmental Characteristics in the Transmission of Intestinal Parasitic Infections.

PubMed

Sahimin, Norhidayu; Lim, Yvonne A L; Ariffin, Farnaza; Behnke, Jerzy M; Lewis, John W; Mohd Zain, Siti Nursheena

2016-11-01

A cross-sectional study of intestinal parasitic infections amongst migrant workers in Malaysia was conducted. A total of 388 workers were recruited from five sectors including manufacturing, construction, plantation, domestic and food services. The majority were recruited from Indonesia (n = 167, 43.3%), followed by Nepal (n = 81, 20.9%), Bangladesh (n = 70, 18%), India (n = 47, 12.1%) and Myanmar (n = 23, 5.9.2%). A total of four nematode species (Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis and hookworms), one cestode (Hymenolepis nana) and three protozoan species (Entamoeba histolytica/dispar, Giardia sp. and Cryptosporidium spp.) were identified. High prevalence of infections with A. lumbricoides (43.3%) was recorded followed by hookworms (13.1%), E. histolytica/dispar (11.6%), Giardia sp. (10.8%), T. trichura (9.5%), Cryptosporodium spp. (3.1%), H. nana (1.8%) and E. vermicularis (0.5%). Infections were significantly influenced by socio-demographic (nationality), and environmental characteristics (length of working years in the country, employment sector and educational level). Up to 84.0% of migrant workers from Nepal and 83.0% from India were infected with intestinal parasites, with the ascarid nematode A. lumbricoides occurring in 72.8% of the Nepalese and 68.1% of the Indian population. In addition, workers with an employment history of less than a year or newly arrived in Malaysia were most likely to show high levels of infection as prevalence of workers infected with A. lumbricoides was reduced from 58.2% to 35.4% following a year's residence. These findings suggest that improvement is warranted in public health and should include mandatory medical screening upon entry into the country.

Goats in the city: prevalence of Giardia duodenalis and Cryptosporidium spp. in extensively reared goats in northern India.

PubMed

Utaaker, Kjersti Selstad; Myhr, Nina; Bajwa, Rajinder Singh; Joshi, Himanshu; Kumar, Anil; Robertson, Lucy J

2017-12-22

Various characteristics of goats mean they are highly suitable livestock for backyard rearing by people with limited resources. They are a popular livestock choice in India, where they are often kept to supplement an already scarce income. In these settings, hygiene and sanitation standards tend to be low, and weakens the interface between humans and animals, thus reducing the barrier between them and thereby increasing the likelihood that zoonotic and anthroponotic infections will occur. This study reports an investigation of the occurrence of Cryptosporidium spp. and Giardia duodenalis in goats being reared in different settings in urban and peri-urban areas in northern India, and addressed the zoonotic potential of these important protozoan parasites shed from goats living close to humans. The overall prevalence of G. duodenalis was 33.8 and 0.5% for Cryptosporidium spp.; the relatively low prevalence of cryptosporidiosis may reflect that most samples were derived from adult animals. The prevalence of G. duodenalis excretion was found to be similar to that reported in other studies. However, although other studies have reported a predominance of non-zoonotic Assemblage E in goats, in this study potentially zoonotic Assemblages predominated [Assemblage A (36%) and Assemblage B (32%)]. The results of this study indicate that in this area where goats and humans are living in close proximity, there may be sharing of intestinal parasites, which can be detrimental for both host species.

Occurrence of Cryptosporidium, Giardia, and Cyclospora in influent and effluent water at wastewater treatment plants in Arizona.

PubMed

Kitajima, Masaaki; Haramoto, Eiji; Iker, Brandon C; Gerba, Charles P

2014-06-15

We investigated the occurrence of Cryptosporidium, Giardia, and Cyclospora at two wastewater treatment plants (WWTPs) in Arizona over a 12-month period, from August 2011 to July 2012. Influent and effluent wastewater samples were collected monthly, and protozoan (oo)cysts were concentrated using an electronegative filter, followed by the detection of protozoa using fluorescent microscopy (Cryptosporidium oocysts and Giardia cysts) and PCR-based methods (Cryptosporidium spp., Giardia intestinalis, and Cyclospora cayetanensis). The concentration of Giardia cysts in the influent was always higher than that of Cryptosporidium oocysts (mean concentration of 4.8-6.4×10(3) versus 7.4×10(1)-1.0×10(2)(oo)cysts/l) with no clear seasonality, and log10 reduction of Giardia cysts was significantly higher than that of Cryptosporidium oocysts for both WWTPs (P<0.05). Log10 reduction of Giardia cysts at the WWTP utilizing activated sludge was significantly higher than the other WWTP using trickling filter (P=0.014), while no statistically significant difference between the two WWTPs was observed for the log10 reduction of Cryptosporidium oocysts (P=0.207). Phylogenetic analysis revealed that G. intestinalis strains identified in wastewater belonged to two assemblages, AII and B, which are potentially infectious to humans. C. cayetanensis was also detected from both influent and effluent using a newly developed quantitative PCR, with the highest influent concentration of 1.2×10(4)copies/l. Our results demonstrated that these protozoan pathogens are prevalent in the study area and that efficacy of the conventional wastewater treatment processes at physically removing (oo)cysts is limited. Copyright © 2014 Elsevier B.V. All rights reserved.

Molecular genotyping of Giardia duodenalis in children from Behbahan, southwestern Iran.

PubMed

Kasaei, Raziyeh; Carmena, David; Jelowdar, Ali; Beiromvand, Molouk

2018-05-01

Giardia duodenalis is an intestinal flagellated protozoan that infects humans and several animal species. Giardiasis causing more than 200 million symptomatic infections globally is one of the most common causes of diarrhea in developing countries. Based on molecular studies mainly targeting the small-subunit (SSU) rRNA gene locus of the parasite, eight assemblages (A to H) have been identified in humans and other animal species. The aim of the current study was to evaluate the frequency and molecular diversity of G. duodenalis in children from rural and urban day care centers from Behbahan, southwestern Iran. This cross-sectional study was based on a concentration method for the microscopic detection of G. duodenalis in stool samples of 450 children, aged 1-7 years, in Behbahan, southwestern Iran. The survey was conducted from December 2015 to May 2016. PCR methods targeting the SSU rRNA and triose phosphate isomerase (TPI) genes of G. duodenalis were used for the identification and genotyping of the parasite isolates. Based on sucrose flotation and microscopy techniques, 2.7% (12/450) of children were infected with G. duodenalis, of which six (50.0%) were males and the other six (50.0%) were females. Overall, 91.7% (11/12) of the infections were detected in children from rural areas. The SSU rRNA and TPI genes were amplified successfully in nine and eight, respectively, of the Giardia-positive samples at microscopy. Among the eight TPI sequences, assemblage A, sub-assemblage AII, was identified in five of the isolates. The sequences of the three remaining samples were untypable. Although no significantly statistical difference between genotype and clinical symptoms was found, five out of the eight isolates identified as assemblage A were obtained in asymptomatic children. Giardia duodenalis infections were more prevalent in children from rural day care schools, and the predominant assemblage was A, sub-assemblage AII. The higher prevalence of giardiasis in rural areas might be related to differences in personal hygiene habits, parents' education level, source of drinking water, and inadequate hygienic toilet facilities in rural areas.

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

PubMed Central

2010-01-01

Background The rapid socio-economic development in Qatar in the last two decades has encouraged a mass influx of immigrant workers, the majority of whom originate from countries with low socio-economic levels, inadequate medical care and many are known to carry patent intestinal helminth and protozoan infections on arrival in Qatar. Some eventually acquire residency status but little is known about whether they continue to harbour infections. Methods We examined 9208 hospital records of stool samples that had been analysed for the presence of intestinal helminth and protozoan ova/cysts, over the period 2005-2008, of subjects from 28 nationalities, but resident in Qatar and therefore not recent arrivals in the country. Results Overall 10.2% of subjects were infected with at least one species, 2.6% with helminths and 8.0% with protozoan species. Although hookworms, Ascaris lumbricoides, Trichuris trichiura and Hymenolepis nana were observed, the majority of helminth infections (69%) were caused by hookworms, and these were largely aggregated among 20.0-39.9 year-old male subjects from Nepal. The remaining cases of helminth infection were mostly among Asian immigrants. Protozoan infections were more uniformly spread across immigrants from different regions when prevalence was calculated on combined data, but this disguised three quite contrasting underlying patterns for 3 taxa of intestinal protozoa. Blastocystis hominis, Giardia duodenalis and non-pathogenic amoebae were all acquired in childhood, but whereas prevalence of B. hominis rose to a plateau and then even further among the elderly, prevalence of G. duodenalis fell markedly in children aged 10 and older, and stayed low (< 2%) gradually falling even further in the elderly. In contrast the prevalence of non-pathogenic amoebae (Entamoeba coli, E. hartmanni, Endolimax nana and Iodamoeba buetschlii) peaked in the 30.0-39.9 age group and only then dropped to very low values among the oldest subjects examined. A 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

Parasites and vector-borne diseases in client-owned dogs in Albania. Intestinal and pulmonary endoparasite infections.

PubMed

Shukullari, Enstela; Hamel, Dietmar; Rapti, Dhimitër; Pfister, Kurt; Visser, Martin; Winter, Renate; Rehbein, Steffen

2015-12-01

From March 2010 to April 2011 inclusive, feces from 602 client-owned dogs visiting four small animal clinics in Tirana, Albania, were examined using standard coproscopical techniques including Giardia coproantigen ELISA and immunofluorescent staining of Giardia cysts. Overall, samples of 245 dogs (40.7 %, 95 % CI 36.6-45.6) tested positive for at least one type of fecal endoparasite (protozoan and/or helminth and/or pentastomid) stage, of which 180 (29.9 %, 95 % CI 26.3-33.7) and 129 (21.9 %, 95 % CI 18.2-24.9) tested positive for protozoan or nematode endoparasites, respectively. Fecal forms of at least 14 endoparasites were identified. The most frequently identified stages were those of Giardia (26.4 %), Trichuris (9.5 %), Toxocara (8.0 %), hookworms (7.1 %), Cystoisospora ohioensis (4.3 %), and Cystoisospora canis (3 %). For the first time for dogs in Albania, fecal examination indicated the occurrence of Hammondia/Neospora-like (0.2 %), Angiostrongylus lungworm (0.3 %), capillariid (2.8 %), and Linguatula (0.2 %) infections. Single and multiple infections with up to seven parasites concurrently were found in 152 (25.2 %, 95 % CI 21.8-28.9) and 93 dogs (15.4 %, 95 % CI 12.7-18.6), respectively. On univariate analysis, the dog's age, the dog's purpose (pet, hunting dog, working dog), the dog's habitat (city, suburban, rural), and environment (mainly indoors, indoors with regular outside walking, yard, kennel/run), presence/absence of other dogs and/or cats, history of anthelmintic use, and season of examination were identified as significant (p < 0.05) factors predisposing dogs to various types of endoparasitism while the variables breed (pure breed dogs vs. mixed-breed dogs), gender, and type of food were not significant predictors. Multivariate logistic regression analysis for factors associated with overall endoparasitism revealed that dogs >1 year of age (odds ratio [OR] = 0.64), dogs dewormed at least once per year (OR = 0.35), and dogs tested during spring, summer, and autumn (OR = 0.51, 0.15, and 0.20, respectively) had a significantly lower risk compared with ≤1 year old dogs, dogs not dewormed, or dogs tested during winter. The odds of a dog to be diagnosed positive for endoparasites was 1.56 times higher for dogs living together with other pets than that for a dog without other dogs or cats.

Giardiasis as a neglected disease in Brazil: Systematic review of 20 years of publications.

PubMed

Coelho, Camila Henriques; Durigan, Maurício; Leal, Diego Averaldo Guiguet; Schneider, Adriano de Bernardi; Franco, Regina Maura Bueno; Singer, Steven M

2017-10-01

Giardiasis is an intestinal infection that affects more than two hundred million people annually worldwide; it is caused by the flagellated protozoan Giardia duodenalis. In tropical countries and in low or middle-income settings, like Brazil, its prevalence can be high. There is currently no systematic review on the presence of G. duodenalis in patients, animals or water sources in Brazil. This systematic review was performed according to recommendations established by Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). As databases for our searches, we have used PubMed, Embase, Scopus and the Brazilian database SciELO using the keywords «Giardia*» and «Brazil». This systematic review identified research studies related to G. duodenalis in water, giardiasis in animals, prevalence of giardiasis across Brazilian regions, genotyping of strains isolated in humans, and giardiasis in indigenous populations. We also propose a network of G. duodenalis transmission in Brazil based on genotypes analyses. This is the first time within the last twenty years that a review is being published on the occurrence of G. duodenalis in Brazil, addressing relevant issues such as prevalence, molecular epidemiology and analytical methods for parasite detection.

Giardiasis as a neglected disease in Brazil: Systematic review of 20 years of publications

PubMed Central

Durigan, Maurício; Leal, Diego Averaldo Guiguet; Schneider, Adriano de Bernardi; Franco, Regina Maura Bueno; Singer, Steven M.

2017-01-01

Introduction Giardiasis is an intestinal infection that affects more than two hundred million people annually worldwide; it is caused by the flagellated protozoan Giardia duodenalis. In tropical countries and in low or middle-income settings, like Brazil, its prevalence can be high. There is currently no systematic review on the presence of G. duodenalis in patients, animals or water sources in Brazil. Methods This systematic review was performed according to recommendations established by Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). As databases for our searches, we have used PubMed, Embase, Scopus and the Brazilian database SciELO using the keywords Giardia* and Brazil. Results This systematic review identified research studies related to G. duodenalis in water, giardiasis in animals, prevalence of giardiasis across Brazilian regions, genotyping of strains isolated in humans, and giardiasis in indigenous populations. We also propose a network of G. duodenalis transmission in Brazil based on genotypes analyses. Conclusion This is the first time within the last twenty years that a review is being published on the occurrence of G. duodenalis in Brazil, addressing relevant issues such as prevalence, molecular epidemiology and analytical methods for parasite detection. PMID:29065126

Investigation into potential transmission sources of Giardia duodenalis in a threatened marsupial (Petrogale penicillata).

PubMed

Vermeulen, Elke T; Ashworth, Deborah L; Eldridge, Mark D B; Power, Michelle L

2015-07-01

Assemblages of the protozoan parasite Giardia duodenalis common in humans and domestic species are increasingly identified in wildlife species, raising concern about the spill-over of pathogens from humans and domestic animals into wildlife. Here, the identity and prevalence of G. duodenalis in populations of a threatened marsupial, the brush-tailed rock-wallaby (Petrogale penicillata), was investigated. Identification of G. duodenalis isolates, across three loci (18S rRNA, β-giardin and gdh), from rock-wallaby fecal samples (n = 318) identified an overall detection rate of 6.3%. No significant difference in G. duodenalis detection was found among captive, wild and supplemented populations. Isolates were assigned to the zoonotic assemblages A and B at 18S rRNA, with sub-assemblages AI and BIV identified at the β-giardin and gdh loci, respectively. Assemblages AI and BIV have previously been identified in human clinical cases, but also in domestic animals and wildlife. The identification of these assemblages in brush-tailed rock-wallabies suggests there are transmission routes of G. duodenalis from humans or other animals to Australian wildlife, both in captivity and in the wild. Copyright © 2015 Elsevier B.V. All rights reserved.

microRNAs in parasites and parasite infection

PubMed Central

Zheng, Yadong; Cai, Xuepeng; Bradley, Janette E.

2013-01-01

miRNAs, a subclass of small regulatory RNAs, are present from ancient unicellular protozoans to parasitic helminths and parasitic arthropods. The miRNA-silencing mechanism appears, however, to be absent in a number of protozoan parasites. Protozoan miRNAs and components of their silencing machinery possess features different from other eukaryotes, providing some clues on the evolution of the RNA-induced silencing machinery. miRNA functions possibly associate with neoblast biology, development, physiology, infection and immunity of parasites. Parasite infection can alter host miRNA expression that can favor both parasite clearance and infection. miRNA pathways are, thus, a potential target for the therapeutic control of parasitic diseases. PMID:23392243

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.

Dramatic Decrease in Prevalence of Soil-Transmitted Helminths and New Insights Into Intestinal Protozoa in Children Living in the Chaco Region, Bolivia

PubMed Central

Macchioni, Fabio; Segundo, Higinio; Gabrielli, Simona; Totino, Valentina; Gonzales, Patricia Rojas; Salazar, Esteban; Bozo, Ricardo; Bartoloni, Alessandro; Cancrini, Gabriella

2015-01-01

We assessed the prevalence of intestinal parasites among 268 2–12-year-old children living in rural areas, small villages, and semi-urban areas of the Chaco region, south-eastern Bolivia. The overall parasitism was 69%. Only protozoa, helminths, or co-infections were observed in 89.2%, 5.9%, or 4.9% of the positive children, respectively. A significant progressive increase in overall parasite prevalence was found when passing from rural areas to small villages and semi-urban areas. The most commonly found species were Entamoeba coli (38.4%), Giardia intestinalis (37.7%), and Blastocystis spp. (16%). Hymenolepis nana was the most prevalent helminth (5.6%), followed by Ascaris lumbricoides and hookworms (1.5% and 0.4%) evidenced only in rural areas and in villages. Molecular diagnostics identified Blastocystis subtypes 9 and 2, and 5 infections by Entamoeba histolytica and 4 by Entamoeba dispar. The dramatic decrease in prevalence of soil-transmitted helminths with respect to that observed about 20 years ago (> 40%) evidences the success of the preventive chemotherapy intervention implemented in 1986. Health education and improved sanitation should be intensified to control protozoan infections. PMID:25711609

Crystal structure of a macrophage migration inhibitory factor from Giardia lamblia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buchko, Garry W.; Abendroth, Jan; Robinson, Howard

2013-06-15

Macrophage migration inhibitory factor (MIF) is a eukaryotic cytokine that affects a broad spectrum of immune responses and its activation/inactivation is associated with numerous diseases. During protozoan infections MIF is not only expressed by the host, but, has also been observed to be expressed by some parasites and released into the host. To better understand the biological role of parasitic MIF proteins, the crystal structure of the MIF protein from Giardia lamblia (Gl-MIF), the etiological agent responsible for giardiasis, has been determined at 2.30 Å resolution. The 114-residue protein adopts an α/β fold consisting of a four-stranded β-sheet with twomore » anti-parallel α-helices packed against a face of the β-sheet. An additional short β-strand aligns anti-parallel to β4 of the β-sheet in the adjacent protein unit to help stabilize a trimer, the biologically relevant unit observed in all solved MIF crystal structures to date, and form a discontinuous β-barrel. The structure of Gl-MIF is compared to the MIF structures from humans (Hs-MIF) and three Plasmodium species (falciparum, berghei, and yoelii). The structure of all five MIF proteins are generally similar with the exception of a channel that runs through the center of each trimer complex. Relative to Hs-MIF, there are differences in solvent accessibility and electrostatic potential distribution in the channel of Gl-MIF and the Plasmodium-MIFs due primarily to two “gate-keeper” residues in the parasitic MIFs. For the Plasmodium MIFs the gate-keeper residues are at positions 44 (Y==>R) and 100 (V==>D) and for Gl-MIF it is at position 100 (V==>R). If these gate-keeper residues have a biological function and contribute to the progression of parasitemia they may also form the basis for structure-based drug design targeting parasitic MIF proteins.« less

sequence of Gl-MIF and the other Crystal structure of a macrophage migration inhibitory factor from Giardia lamblia

PubMed Central

Abendroth, Jan; Robinson, Howard; Zhang, Yanfeng; Hewitt, Stephen N.; Edwards, Thomas E.; Van Voorhis, Wesley C.; Myler, Peter J.

2013-01-01

Macrophage migration inhibitory factor (MIF) is a eukaryotic cytokine that affects a broad spectrum of immune responses and its activation/inactivation is associated with numerous diseases. During protozoan infections MIF is not only expressed by the host, but, has also been observed to be expressed by some parasites and released into the host. To better understand the biological role of parasitic MIF proteins, the crystal structure of the MIF protein from Giardia lamblia (Gl-MIF), the etiological agent responsible for giardiasis, has been determined at 2.30 Å resolution. The 114-residue protein adopts an α/β fold consisting of a four-stranded β-sheet with two anti-parallel α-helices packed against a face of the β-sheet. An additional short β-strand aligns anti-parallel to β4 of the β-sheet in the adjacent protein unit to help stabilize a trimer, the biologically relevant unit observed in all solved MIF crystal structures to date, and form a discontinuous β-barrel. The structure of Gl-MIF is compared to the MIF structures from humans (Hs-MIF) and three Plasmodium species (falciparum, berghei, and yoelii). The structure of all five MIF proteins are generally similar with the exception of a channel that runs through the center of each trimer complex. Relative to Hs-MIF, there are differences in solvent accessibility and electrostatic potential distribution in the channel of Gl-MIF and the Plasmodium-MIFs due primarily to two “gate-keeper” residues in the parasitic MIFs. For the Plasmodium MIFs the gate-keeper residues are at positions 44 (Y⇒R) and 100 (V⇒D) and for Gl-MIF it is at position 100 (V⇒R). If these gate-keeper residues have a biological function and contribute to the progression of parasitemia they may also form the basis for structure-based drug design targeting parasitic MIF proteins. PMID:23709284

Molecular systematics of the parasitic protozoan Giardia intestinalis.

PubMed

Monis, P T; Andrews, R H; Mayrhofer, G; Ey, P L

1999-09-01

The long-standing controversy regarding whether Giardia intestinalis is a single species prevalent in both human and animal hosts or a species complex consisting of morphologically similar organisms that differ in host range and other biotypic characteristics is an issue with important medical, veterinary, and environmental management implications. In the past decade, highly distinct genotypes (some apparently confined to particular host groups) have been identified by genetic analysis of samples isolated from different host species. The aim of this study was to undertake a phylogenetic analysis of G. intestinalis that were representative of all known major genetic groups and compare them with other Giardia species, viz. G. ardeae, G. muris, and G. microti. Segments from four "housekeeping" genes (specifying glutamate dehydrogenase, triose phosphate isomerase, elongation factor 1 alpha, and 18S ribosomal RNA) were examined by analysis of 0.48-0.69-kb nucleotide sequences determined from DNA amplified in polymerase chain reactions from each locus. In addition, isolates were compared by allozymic analysis of electrophoretic data obtained for 21 enzymes representing 23 gene loci. The results obtained from these independent techniques and different loci were essentially congruous. Analyses using G. ardeae and/or G. muris as outgroups supported the monophyly of G. intestinalis and also showed that this species includes genotypes that represent at least seven deeply rooted lineages, herein designated assemblages A-G. Inclusion of G. microti in the analysis of 18S rRNA sequence data demonstrated the monophyly of Giardia with the same median body morphology but did not support the monophyly of G. intestinalis, instead placing G. microti within G. intestinalis. The findings support the hypothesis that G. intestinalis is a species complex and suggest that G. microti is a member of this complex.

Diagnosis of AIDS-Related Intestinal Parasites

DTIC Science & Technology

1990-06-20

previously in ELISA tests to detect antigens of either Giardia lamblia or Entamoeba histolytica in human fecal specimens (67,68), the mean optical...techniques. Eight other intestinal parasites were idtritified Giardia lamblia (67 specimens), Endoimax nana (38 specimens), Entamoeba coli (34 specimens...tests to detect antigens of Entamoeba histolytica or Giardia lamblia in fecal specimens are now truly well-established and have been developed by at

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.

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

Development of a quantitative PCR (qPCR) for Giardia and analysis of the prevalence, cyst shedding and genotypes of Giardia present in sheep across four states in Australia.

PubMed

Yang, Rongchang; Jacobson, Caroline; Gardner, Graham; Carmichael, Ian; Campbell, Angus J D; Ryan, Una

2014-02-01

A novel quantitative PCR (qPCR) for Giardia at the glutamate dehydrogenase (gdh) locus was developed and validated. The qPCR was used to screen a total of 3412 lamb faecal samples collected from approximately 1189 lambs at three sampling periods (weaning, post-weaning and pre-slaughter) from eight farms across South Australia (SA), New South Wales (NSW), Victoria (Vic) and Western Australia (WA). The overall prevalence was 20.2% (95% CI 18.9-21.6) and of the 690 positives, 473 were successfully typed. In general, the prevalence of Giardia varied widely across the different farms with the highest prevalence in one WA farm (42.1%) at pre-slaughter sampling and the lowest prevalence in one Victorian farm (7.2%) at weaning. The range of cyst shedding at weaning, post-weaning and pre-slaughter overall across all states was 63-1.3×10(9) cysts g(-1) (median=1.7×10(4)), 63-1.1×10(9) cysts g(-1) (median=9.6×10(3)), 63-4.7×10(9) cysts g(-1) (median=8.1×10(4)) respectively. Assemblage specific primers at the triose phosphate isomerase (tpi) locus identified assemblage A in 22.4% (106/473) of positive samples typed, assemblage E in 75.9% (359/473) and mixed A and E assemblages in 1.7% (8/473) of samples. A subset of representative samples from the 8 farms (n=32) were typed at both the gdh and beta-giardin loci and confirmed these results and identified sub-assemblage AII in 16 representative assemblage A isolates across the 8 farms. This demonstrates a prevalence of Giardia previously not recognised in Australian sheep, highlighting a need for further research to quantify the production impacts of this protozoan parasite. Copyright © 2013 Elsevier Inc. All rights reserved.

Lectin Activation in Giardia lamblia by Host Protease: A Novel Host-Parasite Interaction

NASA Astrophysics Data System (ADS)

Lev, Boaz; Ward, Honorine; Keusch, Gerald T.; Pereira, Miercio E. A.

1986-04-01

A lectin in Giardia lamblia was activated by secretions from the human duodenum, the environment where the parasite lives. Incubation of the secretions with trypsin inhibitors prevented the appearance of lectin activity, implicating proteases as the activating agent. Accordingly, lectin activation was also produced by crystalline trypsin and Pronase; other proteases tested were ineffective. When activated, the lectin agglutinated intestinal cells to which the parasite adheres in vivo. The lectin was most specific to mannose-6-phosphate and apparently was bound to the plasma membrane. Activation of a parasite lectin by a host protease represents a novel mechanism of hostparasite interaction and may contribute to the affinity of Giardia lamblia to the infection site.

[Measuring resistant forms of two pathogenic protozoa (Giardia spp and Cryptosporidium spp) in two aquatic biotopes in Yaoundé (Cameroon)].

PubMed

Gideon, Aghaindum Ajeagah; Njiné, Thomas; Nola, Moïse; Menbohan, Samuel Foto; Ndayo, Marguerite Wouafo

2007-01-01

Organisms of the genera Cryptosporidium and Giardia are enteric parasites that are responsible for cryptosporidiosis and giardiasis respectively. They are characterised by profuse diarrhoea, abdominal pain and cramping. The symptoms can be fatal for immunodepressed subjects and children because these are opportunistic pathogens. These pathogenic infections are rampant in developing countries due to the unhygienic and improper disposal of wastewater and the use of surface water as the major sources of potable water. Little information is available about the resistant forms of these microorganisms in the hydrosystems of Cameroon in particular and other sub-Saharan ecosystems in general. The aim of this research was to isolate, identify, and measure these forms of these emerging protozoa in the waste and surface waters of Yaoundé, Cameroon. Giardia spp cysts were identified by Lugol iodine staining, and the Cryptosporidium spp oocysts by the Ziehl-Neelsen technique. The cysts were oval in structure and varied in length from 7 um to 12.0 um. Axostyles were visible along the median line and nuclei were present. The oocysts were round in structure and varied in diameter from 4 um to 6 um. A double cell wall was seen in the apicomplexa. The highest concentrations of Giardia spp cysts were 560 cysts/L in the surface water and 650 cysts/L in the residual effluent, while the corresponding figures for Cryptosporidium spp were 1,110 oocysts/L in the stream and 1,500 oocysts/L in the effluent. The cyst and oocyst counts were higher in the direct effluent because they are released directly into the wastewater by feces, while they are diluted in the surface water, reducing their abundance. Turbidity has a significant effect (p<0.05) on the population dynamics of these microorganisms, thereby indicating the importance of suspended or colloidal particles in the dissemination of these pathogens in aquatic media. The suspended particles in the wastewater adsorb the oocysts and cysts, probably because of the interactions between the electric charges carried by suspended particles and those present at the surface of the parasites. The positive correlation observed between these parasites and ammonia may account for some of the die-off of these resistant forms, because ammonium ions in water are known to inactivate trophozoites and sporozoites present in cysts and oocysts. This may be due to the permeability of the protozoan membrane to the ammonium ion and other alkaline earth metals present in aqueous form in the biotope. These parasite forms in these media represent a considerable health risk to the inhabitants of the study zone who depend on this surface water for drinking. The small size of these parasitic forms, the nonfunctional water purification stations and ineffective water treatment systems expose the community to outbreaks of giardiasis and cryptosporidiosis.

Factors related to occurrence and distribution of selected bacterial and protozoan pathogens in Pennsylvania streams

USGS Publications Warehouse

Duris, Joseph W.; Reif, Andrew G.; Donna A. Crouse,; Isaacs, Natasha M.

2013-01-01

The occurrence and distribution of fecal indicator bacteria (FIB) and bacterial and protozoan pathogens are controlled by diverse factors. To investigate these factors in Pennsylvania streams, 217 samples were collected quarterly from a 27-station water-quality monitoring network from July 2007 through August 2009. Samples were analyzed for concentrations of Escherichia coli (EC) and enterococci (ENT) indicator bacteria, concentrations of Cryptosporidium oocysts and Giardia cysts, and the presence of four genes related to pathogenic types of EC (eaeA, stx2, stx1, rfbO157) plus three microbial source tracking (MST) gene markers that are also associated with pathogenic ENT and EC (esp, LTIIa, STII). Water samples were concurrently analyzed for basic water chemistry, physical measures of water quality, nutrients, metals, and a suite of 79 organic compounds that included hormones, pharmaceuticals, and antibiotics. For each sample location, stream discharge was measured by using standardized methods at the time of sample collection, and ancillary sample site information, such as land use and geological characteristics, was compiled. Samples exceeding recreational water quality criteria were more likely to contain all measured pathogen genes but notCryptosporidium or Giardia (oo)cysts. FIB and Giardia density and frequency of eaeA gene occurrence were significantly related to season. When discharge at a sampling location was high (>75th percentile of daily mean discharge), there were greater densities of FIB and Giardia, and the stx2, rfbO157, STII, and esp genes were found more frequently than at other discharge conditions. Giardia occurrence was likely related to nonpoint sources, which are highly influential during seasonal overland transport resulting from snowmelt and elevated precipitation in late winter and spring in Pennsylvania. When MST markers of human, swine, or bovine origin were present, samples more frequently carried the eaeA, stx2, stx1, and rfbO157 genes, but no genes were related exclusively to an individual MST marker. The human source pharmaceuticals (HSPs) acetaminophen and caffeine were correlated with Giardia, and the presence of HSPs proved to be more useful than MST markers in distinguishing the occurrence of Giardia. The HSPs caffeine and carbamazepine were correlated with the sum total of pathogen genes detected in a sample, demonstrating the value of using HSPs as an indicator of fecally derived pathogens. Sites influenced by urban land use with less forest were more likely to have greater FIB and Giardia densities and sum of the array of pathogen genes. Sites dominated by shallow carbonate bedrock in the upstream catchment were likely to have greater FIB densities and higher sum totals of pathogen genes but no correlation with Giardia detection. Our study provides a range of specific environmental, chemical, geologic, and land-use variables related to occurrence and distribution of FIB and selected bacterial and protozoan pathogens in Pennsylvania streams. The information presented could be useful for resource managers in understanding bacterial and protozoan pathogen occurrence and their relation to fecal indicator bacteria in similar settings.

Evolution of apoptosis-like programmed cell death in unicellular protozoan parasites.

PubMed

Kaczanowski, Szymon; Sajid, Mohammed; Reece, Sarah E

2011-03-25

Apoptosis-like programmed cell death (PCD) has recently been described in multiple taxa of unicellular protists, including the protozoan parasites Plasmodium, Trypanosoma and Leishmania. Apoptosis-like PCD in protozoan parasites shares a number of morphological features with programmed cell death in multicellular organisms. However, both the evolutionary explanations and mechanisms involved in parasite PCD are poorly understood. Explaining why unicellular organisms appear to undergo 'suicide' is a challenge for evolutionary biology and uncovering death executors and pathways is a challenge for molecular and cell biology. Bioinformatics has the potential to integrate these approaches by revealing homologies in the PCD machinery of diverse taxa and evaluating their evolutionary trajectories. As the molecular mechanisms of apoptosis in model organisms are well characterised, and recent data suggest similar mechanisms operate in protozoan parasites, key questions can now be addressed. These questions include: which elements of apoptosis machinery appear to be shared between protozoan parasites and multicellular taxa and, have these mechanisms arisen through convergent or divergent evolution? We use bioinformatics to address these questions and our analyses suggest that apoptosis mechanisms in protozoan parasites and other taxa have diverged during their evolution, that some apoptosis factors are shared across taxa whilst others have been replaced by proteins with similar biochemical activities.

Evolution of apoptosis-like programmed cell death in unicellular protozoan parasites

PubMed Central

2011-01-01

Apoptosis-like programmed cell death (PCD) has recently been described in multiple taxa of unicellular protists, including the protozoan parasites Plasmodium, Trypanosoma and Leishmania. Apoptosis-like PCD in protozoan parasites shares a number of morphological features with programmed cell death in multicellular organisms. However, both the evolutionary explanations and mechanisms involved in parasite PCD are poorly understood. Explaining why unicellular organisms appear to undergo 'suicide' is a challenge for evolutionary biology and uncovering death executors and pathways is a challenge for molecular and cell biology. Bioinformatics has the potential to integrate these approaches by revealing homologies in the PCD machinery of diverse taxa and evaluating their evolutionary trajectories. As the molecular mechanisms of apoptosis in model organisms are well characterised, and recent data suggest similar mechanisms operate in protozoan parasites, key questions can now be addressed. These questions include: which elements of apoptosis machinery appear to be shared between protozoan parasites and multicellular taxa and, have these mechanisms arisen through convergent or divergent evolution? We use bioinformatics to address these questions and our analyses suggest that apoptosis mechanisms in protozoan parasites and other taxa have diverged during their evolution, that some apoptosis factors are shared across taxa whilst others have been replaced by proteins with similar biochemical activities. PMID:21439063

Genomic minimalism in the early diverging intestinal parasite Giardia lamblia.

PubMed

Morrison, Hilary G; McArthur, Andrew G; Gillin, Frances D; Aley, Stephen B; Adam, Rodney D; Olsen, Gary J; Best, Aaron A; Cande, W Zacheus; Chen, Feng; Cipriano, Michael J; Davids, Barbara J; Dawson, Scott C; Elmendorf, Heidi G; Hehl, Adrian B; Holder, Michael E; Huse, Susan M; Kim, Ulandt U; Lasek-Nesselquist, Erica; Manning, Gerard; Nigam, Anuranjini; Nixon, Julie E J; Palm, Daniel; Passamaneck, Nora E; Prabhu, Anjali; Reich, Claudia I; Reiner, David S; Samuelson, John; Svard, Staffan G; Sogin, Mitchell L

2007-09-28

The genome of the eukaryotic protist Giardia lamblia, an important human intestinal parasite, is compact in structure and content, contains few introns or mitochondrial relics, and has simplified machinery for DNA replication, transcription, RNA processing, and most metabolic pathways. Protein kinases comprise the single largest protein class and reflect Giardia's requirement for a complex signal transduction network for coordinating differentiation. Lateral gene transfer from bacterial and archaeal donors has shaped Giardia's genome, and previously unknown gene families, for example, cysteine-rich structural proteins, have been discovered. Unexpectedly, the genome shows little evidence of heterozygosity, supporting recent speculations that this organism is sexual. This genome sequence will not only be valuable for investigating the evolution of eukaryotes, but will also be applied to the search for new therapeutics for this parasite.

[Distribution of entero-parasitic infections in the Peruvian Highland: study carried out in six rural communities of the department of Puno, Peru].

PubMed

Maco Flores, Vicente; Marcos Raymundo, Luis A; Terashima Iwashita, Angélica; Samalvides Cuba, Frine; Gotuzzo Herencia, Eduardo

2002-01-01

A prevalence study was carried out in six rural communities in the Peruvian Highlands with the purpose of achieving a better understanding of the distribution of entero-parasites. The communities were located along the banks of Lake Titicaca, in the provinces of Puno and El Collao, Department of Puno, Peru, at 3,800 m.a.s.l. To that effect, a total of 91 feces samples of adults and children from the following communities were analyzed: Conchaca, Puñutani, Capalla, Culta, Maraesqueña, and Jaillihuaya. Analysis techniques included Direct Examination, Kato Technique, Technique of Spontaneous Sedimentation in a Test Tube and the Lumbreras Rapid Sedimentation Technique. The general prelavence of intestinal parasitosis was found to be 91.2%. The pathogenic entero-parasites found were, in order of frequency, as follows: Hymenolepis nana 6.6%, Entamoeba histolytica 5.5%, Giardia lamblia 3.3%, Taenia sp. 2.2%, Ascaris lumbricoides 2.2%, Trichuris trichiura 1.1%, and Enterobius vermicularis 1.1%. The frequency of the non-pathogenic entero-parasites was as follows: Entamoeba coli 78%, Endolimax nana 39.6%, Iodamoeba butschlii 14.3%, Blastocystis hominis 9.9%, and Chilomastix mesnili 2.2%. Most of the patients had poly parasitism (58.2%), and protozoan infections prevailed over helminthic infection. From the total number of patients infected, 41.8% had one parasite, 33.0% had two parasites, 11.0% had three parasites, 4.4% had four parasites, and 1.1% had five parasites. These results show the high rates of parasitism in the rural population on the banks of Lake Titicaca, which would be associated with socioeconomic factors and the poor environmental sanitation conditions in this area.

Clinical and subclinical infections with Giardia and Cryptosporidium in animals

USDA-ARS?s Scientific Manuscript database

Giardia and Cryptosporidium are frequent parasites of livestock, companion animals, and wildlife, raising questions about the clinical significance of such infections. Infections with both parasites have a wide spectrum of symptoms that can vary between asymptomatic infections to serious infection ...

A retrospective investigation of feline gastrointestinal parasites in western Canada

PubMed Central

Hoopes, Jessica H.; Polley, Lydden; Wagner, Brent; Jenkins, Emily J.

2013-01-01

Between 1998 and 2008, feline fecal specimens were submitted to provincial veterinary diagnostic laboratories in Regina and Saskatoon, Saskatchewan, for sucrose centrifugation-flotation (n = 635), parasite identification (n = 17), and/or Giardia (n = 283) or Cryptosporidium (n = 266) commercial direct immunofluorescence assay (IFA). The most commonly detected parasites on flotation were Toxocara cati (4.7%), Isospora (3.8%), and taeniid eggs (Echinococcus or Taenia) (1.3%). Cats less than 2 years of age were twice as likely to have a positive parasite test as cats older than 2 years. Using IFA, Giardia was detected in 9.9% of samples, and Cryptosporidium in 2.3% of samples. Relative to IFA, flotation had sensitivity values of 39% and 50% for detection of Giardia and Cryptosporidium, respectively. Giardia and Isospora were detected in a higher proportion of samples in our study population than reported in the general cat population in western Canada. This study highlights the importance of sensitivity when interpreting diagnostic tests and provides information to guide region-specific recommendations for helminth parasite prevention and treatment. PMID:24082162

Foodborne Protozoans

USDA-ARS?s Scientific Manuscript database

Identification of the human pathogens Cryptosporidium and Giardia can be grouped into general morphology by microscopy, chemical and immunofluorescent staining methods aiding microscopy, and biochemical and molecular tests. Microscopic observations can be made using brightfield with or without spec...

A novel in vitro image-based assay identifies new drug leads for giardiasis.

PubMed

Hart, Christopher J S; Munro, Taylah; Andrews, Katherine T; Ryan, John H; Riches, Andrew G; Skinner-Adams, Tina S

2017-04-01

Giardia duodenalis is an intestinal parasite that causes giardiasis, a widespread human gastrointestinal disease. Treatment of giardiasis relies on a small arsenal of compounds that can suffer from limitations including side-effects, variable treatment efficacy and parasite drug resistance. Thus new anti-Giardia drug leads are required. The search for new compounds with anti-Giardia activity currently depends on assays that can be labour-intensive, expensive and restricted to measuring activity at a single time-point. Here we describe a new in vitro assay to assess anti-Giardia activity. This image-based assay utilizes the Perkin-Elmer Operetta ® and permits automated assessment of parasite growth at multiple time points without cell-staining. Using this new approach, we assessed the "Malaria Box" compound set for anti-Giardia activity. Three compounds with sub-μM activity (IC 50 0.6-0.9 μM) were identified as potential starting points for giardiasis drug discovery. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system, Paraná, Southern Brazil.

PubMed

Almeida, Jonatas Campos; Martins, Felippe Danyel Cardoso; Ferreira Neto, José Maurício; Santos, Maíra Moreira Dos; Garcia, João Luis; Navarro, Italmar Teodorico; Kuroda, Emília Kiyomi; Freire, Roberta Lemos

2015-01-01

The purpose of this study was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system. Samples of raw and treated water were collected and concentrated using the membrane filtration technique. Direct Immunofluorescence Test was performed on the samples. DNA extraction using a commercial kit was performed and the DNA extracted was submitted to a nested-PCR reaction (n-PCR) and sequencing. In the immunofluorescence, 2/24 (8.33%) samples of raw water were positive for Giardia spp.. In n-PCR and sequencing, 2/24 (8.33%) samples of raw water were positive for Giardia spp., and 2/24 (8.33%) samples were positive for Cryptosporidium spp.. The sequencing showed Cryptosporidium parvum and Giardia duodenalis DNA. In raw water, there was moderate correlation among turbidity, color and Cryptosporidium spp. and between turbidity and Giardia spp.. The presence of these protozoans in the water indicates the need for monitoring for water-treatment companies.

COMPARISON OF MICROSCOPIC VERSUS MOLECULAR DIAGNOSIS OF CYCLOSPORA CAYETANENSIS

EPA Science Inventory

Objective: to investigate several ways to diagnose the food and waterborne protozoan parasite Cyclospora cayetanensis. Cyclospora cayetanensis is a protozoan parasite that infects human beings and causes gastroenteritis. Diagnosis of this parasite is complicated by the fact th...

Molecular diversity and frequency of the diarrheagenic enteric protozoan Giardia duodenalis and Cryptosporidium spp. in a hospital setting in Northern Spain.

PubMed

Azcona-Gutiérrez, José Manuel; de Lucio, Aida; Hernández-de-Mingo, Marta; García-García, Concepción; Soria-Blanco, Luis Miguel; Morales, Lucía; Aguilera, María; Fuentes, Isabel; Carmena, David

2017-01-01

Human giardiosis and cryptosporidiosis are caused by the enteric protozoan parasites Giardia duodenalis and Cryptosporidium spp. Both pathogens are major contributors to the global burden of diarrhoeal disease, affecting primarily children and immunodebilitated individuals in resource-poor settings. Giardiosis and cryptosporidiosis also represent an important, often underestimate, public health threat in developed countries. In Spain only limited information is currently available on the epidemiology of these infections. Molecular data on the diversity, frequency, geographical distribution, and seasonality of G. duodenalis assemblages/sub-assemblages and Cryptosporidium species/sub-genotypes are particularly scarce. A longitudinal molecular epidemiological survey was conducted between July 2015 to September 2016 in patients referred to or attended at the Hospital San Pedro (La Rioja, Northern Spain) that tested positive for G. duodenalis (N = 106) or Cryptosporidium spp. (N = 103) by direct microscopy and/or a rapid lateral flow immunochromatographic assay. G. duodenalis infections were subsequently confirmed by real-time PCR and positive isolates assessed by multi-locus sequence genotyping of the glutamate dehydrogenase and β-giardin genes of the parasite. Cryptosporidium species and sub-genotypes were investigated at the 60 kDa glycoprotein or the small subunit ribosomal RNA genes of the parasite. Sociodemographic and clinical parameters of infected patients were also gathered and analysed. Out of 90 G. duodenalis-positive isolates by real-time PCR a total of 16 isolates were successfully typed. AII (44%, 7/16) was the most prevalent sub-assemblage found, followed by BIV (31%, 5/16) and BIII (19%, 3/16). A discordant genotype result AII/AIII was identified in an additional (6%, 1/16) isolate. No mixed infections A+B were detected. Similarly, a total of 81 Cryptosporidium spp. isolates were successfully typed, revealing the presence of C. hominis (81%, 66/81) and C. parvum (19%, 15/81). Obtained GP60 sequences were assigned to sub-type families Ib (73%, 59/81) within C. hominis, and IIa (7%, 6/81) and IId (2%, 2/81) within C. parvum. A marked inter-annual variation in Cryptosporidium cases was observed. Human giardiasis and cryptosporidiosis are commonly identified in patients seeking medical care in Northern Spain and represent a more important health concern than initially thought. Assemblage A within G. duodenalis and sub-genotype IbA10G2 within C. hominis were the genetic variants of these parasite species more frequently found circulating in the population under study. Molecular data presented here seem to suggest that G. duodenalis and Cryptosporidium infections arise through anthroponotic rather than zoonotic transmission in this Spanish region.

Transcriptomic Profiling of High-Density Giardia Foci Encysting in the Murine Proximal Intestine.

PubMed

Pham, Jonathan K; Nosala, Christopher; Scott, Erica Y; Nguyen, Kristofer F; Hagen, Kari D; Starcevich, Hannah N; Dawson, Scott C

2017-01-01

Giardia is a highly prevalent, understudied protistan parasite causing significant diarrheal disease worldwide. Its life cycle consists of two stages: infectious cysts ingested from contaminated food or water sources, and motile trophozoites that colonize and attach to the gut epithelium, later encysting to form new cysts that are excreted into the environment. Current understanding of parasite physiology in the host is largely inferred from transcriptomic studies using Giardia grown axenically or in co-culture with mammalian cell lines. The dearth of information about the diversity of host-parasite interactions occurring within distinct regions of the gastrointestinal tract has been exacerbated by a lack of methods to directly and non-invasively interrogate disease progression and parasite physiology in live animal hosts. By visualizing Giardia infections in the mouse gastrointestinal tract using bioluminescent imaging (BLI) of tagged parasites, we recently showed that parasites colonize the gut in high-density foci. Encystation is initiated in these foci throughout the entire course of infection, yet how the physiology of parasites within high-density foci in the host gut differs from that of cells in laboratory culture is unclear. Here we use BLI to precisely select parasite samples from high-density foci in the proximal intestine to interrogate in vivo Giardia gene expression in the host. Relative to axenic culture, we noted significantly higher expression (>10-fold) of oxidative stress, membrane transporter, and metabolic and structural genes associated with encystation in the high-density foci. These differences in gene expression within parasite foci in the host may reflect physiological changes associated with high-density growth in localized regions of the gut. We also identified and verified six novel cyst-specific proteins, including new components of the cyst wall that were highly expressed in these foci. Our in vivo transcriptome data support an emerging view that parasites encyst early in localized regions in the gut, possibly as a consequence of nutrient limitation, and also impact local metabolism and physiology.

Transcriptomic Profiling of High-Density Giardia Foci Encysting in the Murine Proximal Intestine

PubMed Central

Pham, Jonathan K.; Nosala, Christopher; Scott, Erica Y.; Nguyen, Kristofer F.; Hagen, Kari D.; Starcevich, Hannah N.; Dawson, Scott C.

2017-01-01

Giardia is a highly prevalent, understudied protistan parasite causing significant diarrheal disease worldwide. Its life cycle consists of two stages: infectious cysts ingested from contaminated food or water sources, and motile trophozoites that colonize and attach to the gut epithelium, later encysting to form new cysts that are excreted into the environment. Current understanding of parasite physiology in the host is largely inferred from transcriptomic studies using Giardia grown axenically or in co-culture with mammalian cell lines. The dearth of information about the diversity of host-parasite interactions occurring within distinct regions of the gastrointestinal tract has been exacerbated by a lack of methods to directly and non-invasively interrogate disease progression and parasite physiology in live animal hosts. By visualizing Giardia infections in the mouse gastrointestinal tract using bioluminescent imaging (BLI) of tagged parasites, we recently showed that parasites colonize the gut in high-density foci. Encystation is initiated in these foci throughout the entire course of infection, yet how the physiology of parasites within high-density foci in the host gut differs from that of cells in laboratory culture is unclear. Here we use BLI to precisely select parasite samples from high-density foci in the proximal intestine to interrogate in vivo Giardia gene expression in the host. Relative to axenic culture, we noted significantly higher expression (>10-fold) of oxidative stress, membrane transporter, and metabolic and structural genes associated with encystation in the high-density foci. These differences in gene expression within parasite foci in the host may reflect physiological changes associated with high-density growth in localized regions of the gut. We also identified and verified six novel cyst-specific proteins, including new components of the cyst wall that were highly expressed in these foci. Our in vivo transcriptome data support an emerging view that parasites encyst early in localized regions in the gut, possibly as a consequence of nutrient limitation, and also impact local metabolism and physiology. PMID:28620589

Intestinal parasites among young children in the interior of Guyana.

PubMed

Lindo, J F; Validum, L; Ager, A L; Campa, A; Cuadrado, R R; Cummings, R; Palmer, C J

2002-03-01

Intestinal parasites contribute greatly to morbidity in developing countries. While there have been several studies of the problem in the Caribbean, including the implementation of control programmes, this has not been done for Guyana. The aim of this study was to determine the prevalence of intestinal parasites among young children in a town located in the interior of Guyana. Eighty-five children under the age of 12 years were studied prospectively for intestinal parasites in Mahdia, Guyana. Stool samples were transported in formalin to the Department of Microbiology, The University of the West Indies, Jamaica, for analysis using the formalin-ether concentration and Ziehl-Neelsen techniques. Data on age and gender of the children were recorded on field data sheets. At least one intestinal parasite was detected in 43.5% (37/85) of the children studied and multiple parasitic infections were recorded in 21.2% (18/85). The most common intestinal helminth parasite was hookworm (28.2%; 24/85), followed by Ascaris lumbricoides (18.8%; 16/85) and then Trichuris trichuria (14.1%; 12/85). Among the protozoan infections Giardia lamblia was detected in 10.5% (9/85) of the study population while Entamoeba histolytica appeared rarely. All stool samples were negative for Cryptosporidium and other intestinal Coccidia. There was no predilection for gender with any of the parasites. The pattern of distribution of worms in this area of Guyana was unlike that seen in other studies. Hookworm infection was the most common among the children and a large proportion had multiple infections. The study established the occurrence and prevalence of a number of intestinal parasites in the population of Guyana. This sets the stage for the design and implementation of more detailed epidemiological studies.

Human intestinal parasites in non-biting synanthropic flies in Ogun State, Nigeria.

PubMed

Adenusi, Adedotun Adesegun; Adewoga, Thomas O Sunday

2013-01-01

Filth-feeding and breeding, non-biting synanthropic flies have been incriminated in the dissemination of human enteropathogens in the environment. This study determined the species of non-biting synanthropic flies associated with four filthy sites in Ilishan, Ogun State, southwest Nigeria, and assessed their potentials for mechanical transmission of human intestinal parasites. 7190 flies identified as Musca domestica (33.94%), Chrysomya megacephala (26.01%), Musca sorbens (23.23%), Lucilia cuprina (8.76%), Calliphora vicina (4.59%), Sarcophaga sp. (2.78%) and Fannia scalaris (0.70%) were examined for human intestinal parasites by the formol-ether concentration and modified Ziehl-Neelsen techniques. Eggs of the following parasites: Ascaris lumbricoides (34.08%), Trichuris trichiura (25.87%), hookworms (20.45%), Taenia sp. (2.36%), Hymenolepis nana (1.11%), Enterobius vermicularis (0.56%), Strongyloides stercoralis (larvae; 3.89%) and cysts of Entamoeba histolytica/dispar (27.26%), Entamoeba coli (22.67%), Giardia lamblia (3.34%) and Cryptosporidium sp. (1.81%) were isolated from the body surfaces and or gut contents of 75.24% of 719 pooled fly batches. The helminths A. lumbricoides and T. trichiura and the protozoans, E. histolytica/dispar and E. coli were the dominant parasites detected, both on body surfaces and in the gut contents of flies. C. megacephala was the highest carrier of parasites (diversity and number). More parasites were isolated from the gut than from body surfaces (P < 0.05). Flies from soiled ground often carried more parasites than those from abattoir, garbage or open-air market. Synanthropic fly species identified in this study can be of potential epidemiological importance as mechanical transmitters of human intestinal parasites acquired naturally from filth and carried on their body surfaces and or in the gut, because of their vagility and feeding mechanisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mechanisms for parasites removal in a waste stabilisation pond.

PubMed

Reinoso, Roberto; Blanco, Saúl; Torres-Villamizar, Linda A; Bécares, Eloy

2011-04-01

A waste stabilisation pond (WSP) system formed by two anaerobic ponds, a facultative pond and a maturation pond was studied from December 2003 to September 2004 in north-western Spain in order to evaluate its efficiency in the removal of faecal indicator bacteria (total coliforms, Escherichia coli, faecal streptococci), coliphages, helminth eggs and protozoan (oo)cysts (Cryptosporidium and Giardia). Furthermore, sediment samples were collected from the bottom of the ponds to assess the settling rates and thus determine the main pathogen removal mechanisms in the WSPs system. The overall removal ranged from 1.4 log units for coliphages in the cold period to 5.0 log units for E. coli in the hot period. Cryptosporidium oocysts were reduced by an average of 96%, Giardia cysts by 98% and helminth eggs by 100%. The anaerobic ponds showed significantly higher surface removal rates (4.6, 5.2 and 3.7 log (oo)cysts/eggs removed m(-2) day(-1), respectively) than facultative and maturation ponds. Sunlight and water physicochemical conditions were the main factors influencing C. parvum oocysts removal both in the anaerobic and maturation ponds, whereas other factors like predation or natural mortality were more important in the facultative pond. Sedimentation, the most commonly proposed mechanism for cyst removal had, therefore, a negligible influence in the studied ponds.

Multiple identification of most important waterborne protozoa in surface water used for irrigation purposes by 18S rRNA amplicon-based metagenomics.

PubMed

Moreno, Y; Moreno-Mesonero, L; Amorós, I; Pérez, R; Morillo, J A; Alonso, J L

2018-01-01

Understanding waterborne protozoan parasites (WPPs) diversity has important implications in public health. In this study, we evaluated a NGS-based method as a detection approach to identify simultaneously most important WPPs using 18S rRNA high-throughput sequencing. A set of primers to target the V4 18S rRNA region of WPPs such as Cryptosporidium spp., Giardia sp., Blastocystis sp., Entamoeba spp, Toxoplasma sp. and free-living amoebae (FLA) was designed. In order to optimize PCR conditions before sequencing, both a mock community with a defined composition of representative WPPs and a real water sample inoculated with specific WPPs DNA were prepared. Using the method proposed in this study, we have detected the presence of Giardia intestinalis, Acanthamoeba castellanii, Toxoplasma gondii, Entamoeba histolytica and Blastocystis sp. at species level in real irrigation water samples. Our results showed that untreated surface irrigation water in open fields can provide an important source of WPPs. Therefore, the methodology proposed in this study can establish a basis for an accurate and effective diagnostic of WPPs to provide a better understanding of the risk associated to irrigation water. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

Gastrointestinal parasites of feral cats from Christmas Island.

PubMed

Adams, P J; Elliot, A D; Algar, D; Brazell, R I

2008-01-01

To investigate the gastrointestinal parasites present in feral cats on Christmas Island, with particular interest in the protozoan parasite Toxoplasma gondii. Faecal and serum samples were collected from 28 and 25 cats respectively that were trapped as part of an ongoing eradication program being run on Christmas Island by the Department of Environment and Conservation. Faecal samples were screened microscopically for helminth and protozoan parasites. Serum samples were screened for antibodies to T gondii using a commercial indirect immunofluorescence assay (IFA) and a latex agglutination test (LAT). The most common helminth parasites detected were Toxocara cati (present in 15 of 28 faecal samples), Strongyloides sp (13/28), Aelurostrongylus abstrusus, (7/28), an unidentified capillarid (6/28) and Ancylostoma sp (4/28). Based on serology, T gondii was the most common parasite detected (protozoan or otherwise) with antibodies detected in 24 serum samples by IFA and 23 serum samples by LAT. Cats on Christmas Island harbour many of the helminth and protozoan parasites reported from feral cats elsewhere in Australia. The high seroprevalence of T gondii in these cats indicates a high level of exposure to the parasite in this environment.

Dramatic decrease in prevalence of soil-transmitted helminths and new insights into intestinal protozoa in children living in the Chaco region, Bolivia.

PubMed

Macchioni, Fabio; Segundo, Higinio; Gabrielli, Simona; Totino, Valentina; Gonzales, Patricia Rojas; Salazar, Esteban; Bozo, Ricardo; Bartoloni, Alessandro; Cancrini, Gabriella

2015-04-01

We assessed the prevalence of intestinal parasites among 268 2-12-year-old children living in rural areas, small villages, and semi-urban areas of the Chaco region, south-eastern Bolivia. The overall parasitism was 69%. Only protozoa, helminths, or co-infections were observed in 89.2%, 5.9%, or 4.9% of the positive children, respectively. A significant progressive increase in overall parasite prevalence was found when passing from rural areas to small villages and semi-urban areas. The most commonly found species were Entamoeba coli (38.4%), Giardia intestinalis (37.7%), and Blastocystis spp. (16%). Hymenolepis nana was the most prevalent helminth (5.6%), followed by Ascaris lumbricoides and hookworms (1.5% and 0.4%) evidenced only in rural areas and in villages. Molecular diagnostics identified Blastocystis subtypes 9 and 2, and 5 infections by Entamoeba histolytica and 4 by Entamoeba dispar. The dramatic decrease in prevalence of soil-transmitted helminths with respect to that observed about 20 years ago (> 40%) evidences the success of the preventive chemotherapy intervention implemented in 1986. Health education and improved sanitation should be intensified to control protozoan infections. © The American Society of Tropical Medicine and Hygiene.

World Association for the Advancement of Veterinary Parasitology (WAAVP): Guideline for the evaluation of drug efficacy against non-coccidial gastrointestinal protozoa in livestock and companion animals.

PubMed

Geurden, T; Olson, M E; O'Handley, R M; Schetters, T; Bowman, D; Vercruysse, J

2014-08-29

The current guideline was written to aid in the design, implementation and interpretation of studies for the assessment of drug efficacy against non-coccidial gastrointestinal protozoan parasites, with Giardia spp. as the leading example. The information provided in this guideline deals with aspects of how to conduct controlled studies using experimental infection models (dose determination and dose confirmation) and efficacy studies in commercial facilities (field effectiveness studies). Furthermore, the selection of suitable animals, housing, infection procedure, choice of diagnostic technique and data analysis are discussed. This guideline is intended to assist investigators in conducting specific studies, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new drugs and to facilitate the worldwide adoption of uniform procedures. The primary parameter for drug efficacy is the reduction in either parasite excretion or parasite counts and a minimum efficacy of 90% is required against non-coccidial gastrointestinal protozoa. A supporting efficacy parameter is a significant difference in the proportion of infected animals between treated and non-treated groups. Persistent efficacy is considered as an additional claim to therapeutic efficacy. Copyright © 2014 Elsevier B.V. All rights reserved.

Disinfection efficacy of sodium dichloroisocyanurate (NADCC) against common food-borne intestinal protozoa.

PubMed

El Zawawy, Lobna A; El-Said, Doaa; Ali, Safia M; Fathy, Fouad M

2010-04-01

The present study was conducted to investigate the efficacy of sodium dichloroisocyanurate (NaDCC) on the infective stages of common food-borne intestinal protozoa; Entamoeba histolytica (E. histolytica), Giardia lamblia (G. lamblia), Cryptosporidium, Cyclospora and Microsporidia; beside its effect on raw green vegetables and fruits. Parasites, isolated from stool of patients with diarrhea or dysentery, were exposed to NaDCC solution (1g/l) for one and two hours. Disinfection effect of NaDCC was assessed by in-vitro viability, using trypan blue stain, and infectivity bioassay in laboratory animals as indicated by fecal and intestinal parasitic counts. Raw vegetables and fruits were dipped in NaDCC solution in the same concentration and exposure time as used for treatment of the parasites. Results revealed statistically significant reductions in viability and infectivity of all examined parasites indicating their susceptibility to NaDCC. Relative variations in susceptibility were revealed; E. histolytica and G. lamblia were most susceptible (100% reduction) followed by Microsporidia then Cryptospridium and Cyclospora. NaDCC did not affect the consistency, color, taste or flavor of raw green vegetables and fruits. The proved efficacy of NaDCC, in cheap and convenient dry tablet form, makes it a promising tool in decontaminating raw vegetables and fruits from food-borne protozoan parasites at household and restaurant levels as well as in catering and fresh produce industry. It is also recommended for disinfection of food preparation surfaces and equipment.

Low sensitivity of the ImmunocardSTAT® Crypto/Giardia Rapid Assay test for the detection of Giardia and Cryptosporidium in fecal samples from children living in Libreville, Central Africa.

PubMed

Bouyou-Akotet, M K; Owono-Medang, M; Moussavou-Boussougou, M N; Mamfoumbi, M Mabika; Mintsa-Nguema, R; Mawili-Mboumba, D P; Kombila, M

2016-12-01

Giardiasis and cryptosporidiosis are now recognized as neglected tropical parasitic diseases. The risk of their dissemination  in developing countries, such as Gabon, is increasing, due to urban crowding and poor sanitation. Accurate, simple and rapid diagnosis tools are thus necessary for the estimation of their real burden. The aim of this study was to evaluate the performances of the ImmunocardSTAT ® Crypto/Giardia Rapid Assay test for the detection of Cryptosporidium ( C. ) spp. and Giardia ( G. ) duodenalis in children living in Libreville, Gabon. Stool samples of 173 healthy children were screened by routine microscopic using the merthiolate iodine formol concentration technique for Giardia , the modified Ziehl Neelsen (ZN) staining for Cryptosporidium and the ImmunocardSTAT ® Crypto/Giardia RDT for the detection of Giardia and Cryptosporidium parasite forms and antigens respectively. G. duodenalis was detected with microscopy and the ImmunocardSTAT ® Crypto/Giardia in 27 (15.6 %) and 22 (13.3 %) fecal samples respectively. C. spp. oocysts were found in 18 (10.4 %) ones, whereas only one sample was positive with the immunochromatographic assay. When microscopic examination was considered as the reference method, sensitivity and specificity of the ImmunocardSTAT ® Crypto/Giardia Rapid Assay were found to be 63.0 %, 96.6 and 5.5 %, 99.3 % for G. duodenalis and C. spp. respectively. The prevalence of G. duodenalis and C. spp. carriage is high in children from Libreville. A low sensitivity of the ImmunocardSTAT ® Crypto/Giardia for the detection of both parasites is observed. It is thus inappropriate as a diagnostic tool for detecting asymptomatic carriers.

ADEQUACY OF DISINFECTION FOR CONTROL OF NEWLY RECOGNIZED WATERBORNE PATHOGENS

EPA Science Inventory

Agents recently recognized as causes or potential causes of waterborne outbreaks include pathogenic bacteria (Campylobacter jejuni, Yersinia enterocoliticia), viruses (rotavirus, Norwalk virus and other poorly defined viral agents) and Giardia lamblia, a protozoan agent. Although...

Evidence for the bacterial origin of genes encoding fermentation enzymes of the amitochondriate protozoan parasite Entamoeba histolytica.

PubMed

Rosenthal, B; Mai, Z; Caplivski, D; Ghosh, S; de la Vega, H; Graf, T; Samuelson, J

1997-06-01

Entamoeba histolytica is an amitochondriate protozoan parasite with numerous bacterium-like fermentation enzymes including the pyruvate:ferredoxin oxidoreductase (POR), ferredoxin (FD), and alcohol dehydrogenase E (ADHE). The goal of this study was to determine whether the genes encoding these cytosolic E. histolytica fermentation enzymes might derive from a bacterium by horizontal transfer, as has previously been suggested for E. histolytica genes encoding heat shock protein 60, nicotinamide nucleotide transhydrogenase, and superoxide dismutase. In this study, the E. histolytica por gene and the adhE gene of a second amitochondriate protozoan parasite, Giardia lamblia, were sequenced, and their phylogenetic positions were estimated in relation to POR, ADHE, and FD cloned from eukaryotic and eubacterial organisms. The E. histolytica por gene encodes a 1,620-amino-acid peptide that contained conserved iron-sulfur- and thiamine pyrophosphate-binding sites. The predicted E. histolytica POR showed fewer positional identities to the POR of G. lamblia (34%) than to the POR of the enterobacterium Klebsiella pneumoniae (49%), the cyanobacterium Anabaena sp. (44%), and the protozoan Trichomonas vaginalis (46%), which targets its POR to anaerobic organelles called hydrogenosomes. Maximum-likelihood, neighbor-joining, and parsimony analyses also suggested as less likely E. histolytica POR sharing more recent common ancestry with G. lamblia POR than with POR of bacteria and the T. vaginalis hydrogenosome. The G. lamblia adhE encodes an 888-amino-acid fusion peptide with an aldehyde dehydrogenase at its amino half and an iron-dependent (class 3) ADH at its carboxy half. The predicted G. lamblia ADHE showed extensive positional identities to ADHE of Escherichia coli (49%), Clostridium acetobutylicum (44%), and E. histolytica (43%) and lesser identities to the class 3 ADH of eubacteria and yeast (19 to 36%). Phylogenetic analyses inferred a closer relationship of the E. histolytica ADHE to bacterial ADHE than to the G. lamblia ADHE. The 6-kDa FD of E. histolytica and G. lamblia were most similar to those of the archaebacterium Methanosarcina barkeri and the delta-purple bacterium Desulfovibrio desulfuricans, respectively, while the 12-kDa FD of the T. vaginalis hydrogenosome was most similar to the 12-kDa FD of gamma-purple bacterium Pseudomonas putida. E. histolytica genes (and probably G. lamblia genes) encoding fermentation enzymes therefore likely derive from bacteria by horizontal transfer, although it is not clear from which bacteria these amebic genes derive. These are the first nonorganellar fermentation enzymes of eukaryotes implicated to have derived from bacteria.

The Occurrence of Some Nonblood Protozoan Parasites in Wild and Domestic Mammals in South Africa.

PubMed

Lukášová, Radka; Halajian, Ali; Bártová, Eva; Kobédová, Kateřina; Swanepoel, Lourens H; O'Riain, M Justin

2018-04-01

Relatively little is known about protozoan parasites in African animals. Here we investigated the occurrence of protozoan parasites in mammals from South Africa. Oocysts of protozoan parasites were detected in 13 of 56 (23%) fecal samples using conventional microscopic examination methods. Cryptosporidium spp. and Cystoisospora spp. were detected in eight (14%) and five (9%) samples, respectively. Mixed parasitic infection of Cryptosporidium spp. and Cystoisospora spp. was recorded in banded mongoose ( Mungos mungo). Cryptosporidium spp. was detected for the first time in cheetah ( Acinonyx jubatus), spotted hyena ( Crocuta crocuta), and African polecat ( Ictonyx striatus). Antibodies to Toxoplasma gondii and Neospora caninum were not detected by enzyme-linked immunosorbent assay in any of 32 sera tested. We detected T. gondii by PCR in tissues of five of 243 (2%) animals: domestic dog ( Canis lupus familiaris), gerbil ( Gerbilliscus spp.), greater kudu ( Tragelaphus strepsiceros), honey badger ( Mellivora capensis), and white-tailed mongoose ( Ichneumia albicauda). Our isolation of T. gondii from white-tailed mongoose and honey badger was a unique finding. All tissue samples were negative for N. caninum. The study increases our knowledge on the occurrence of protozoan parasites in populations of wild and domestic animals in South Africa.

Identification of Giardia lamblia DHHC Proteins and the Role of Protein S-palmitoylation in the Encystation Process

PubMed Central

Merino, María C.; Zamponi, Nahuel; Vranych, Cecilia V.; Touz, María C.; Rópolo, Andrea S.

2014-01-01

Protein S-palmitoylation, a hydrophobic post-translational modification, is performed by protein acyltransferases that have a common DHHC Cys-rich domain (DHHC proteins), and provides a regulatory switch for protein membrane association. In this work, we analyzed the presence of DHHC proteins in the protozoa parasite Giardia lamblia and the function of the reversible S-palmitoylation of proteins during parasite differentiation into cyst. Two specific events were observed: encysting cells displayed a larger amount of palmitoylated proteins, and parasites treated with palmitoylation inhibitors produced a reduced number of mature cysts. With bioinformatics tools, we found nine DHHC proteins, potential protein acyltransferases, in the Giardia proteome. These proteins displayed a conserved structure when compared to different organisms and are distributed in different monophyletic clades. Although all Giardia DHHC proteins were found to be present in trophozoites and encysting cells, these proteins showed a different intracellular localization in trophozoites and seemed to be differently involved in the encystation process when they were overexpressed. dhhc transgenic parasites showed a different pattern of cyst wall protein expression and yielded different amounts of mature cysts when they were induced to encyst. Our findings disclosed some important issues regarding the role of DHHC proteins and palmitoylation during Giardia encystation. PMID:25058047

Guide to the identification of fish protozoan and metazoan parasites in stained tissue sections

USGS Publications Warehouse

Bruno, D.W.; Nowak, B.; Elliott, D.G.

2006-01-01

The identification of protozoan and metazoan parasites is traditionally carried out using a series of classical keys based upon the morphology of the whole organism. However, in stained tissue sections prepared for light microscopy, taxonomic features will be missing, thus making parasite identification difficult. This work highlights the characteristic features of representative parasites in tissue sections to aid identification. The parasite examples discussed are derived from species affecting finfish, and predominantly include parasites associated with disease or those commonly observed as incidental findings in disease diagnostic cases. Emphasis is on protozoan and small metazoan parasites (such as Myxosporidia) because these are the organisms most likely to be missed or mis-diagnosed during gross examination. Figures are presented in colour to assist biologists and veterinarians who are required to assess host/parasite interactions by light microscopy.

Blood parasites of penguins: a critical review.

PubMed

Vanstreels, Ralph Eric Thijl; Braga, Érika Martins; Catão-Dias, José Luiz

2016-07-01

Blood parasites are considered some of the most significant pathogens for the conservation of penguins, due to the considerable morbidity and mortality they have been shown to produce in captive and wild populations of these birds. Parasites known to occur in the blood of penguins include haemosporidian protozoans (Plasmodium, Leucocytozoon, Haemoproteus), piroplamid protozoans (Babesia), kinetoplastid protozoans (Trypanosoma), spirochete bacteria (Borrelia) and nematode microfilariae. This review provides a critical and comprehensive assessment of the current knowledge on these parasites, providing an overview of their biology, host and geographic distribution, epidemiology, pathology and implications for public health and conservation.

Preventing Giardia Infection.

ERIC Educational Resources Information Center

Beer, W. Nicholas

1993-01-01

Outdoor recreationists are at risk for developing giardia infection from drinking contaminated stream water. Giardia is the most common human parasite found in contaminated water that causes gastrointestinal illness. Describes medical treatment and ways of preventing infection through water treatment, including heat, filtration, and chemical…

Giardia spp. and Cryptosporidium spp. In the Ivaí Indigenous Land, Brazil.

PubMed

Nishi, Letícia; Bergamasco, Rosângela; Toledo, Max Jean de Ornelas; Falavigna, Dina Lúcia Morais; Gomes, Mônica Lúcia; Mota, Lúcio Tadeu; Falavigna-Guilherme, Ana Lúcia

2009-10-01

The objective of this study was to investigate the occurrence of cysts of Giardia spp. and oocysts of Cryptosporidium spp. in waters of the Ivaí Indigenous Land, Brazil. Samples of river and spring water and of treated water were filtered and analyzed by direct immunofluorescence (Merifluor kit, Meridian Bioscience, Cincinnati, Ohio). Of 21 samples, 7 from each locality, 3 (3/7, 42.8%) from a river were positive for Giardia (mean concentration 2.57 cysts/L), and 1 (1/7, 14.3%) was positive for Cryptosporidium (6 oocysts/L). From springs, 1 sample (1/7, 14.3%) was positive for Cryptosporidium (6 oocysts/L). One sample (1/7, 14.3%) from treated water was positive for both, with 4 oocysts/L and 2 cysts/L. Giardia was the more frequent protozoan present.

Intestinal Parasites in Children from a Day Care Centre in Matanzas City, Cuba

PubMed Central

Cañete, Roberto; Díaz, Mariuska Morales; Avalos García, Roxana; Laúd Martinez, Pedro Miguel; Manuel Ponce, Félix

2012-01-01

Background Intestinal parasitic infections are widely distributed throughout the world and children are the most affected population. Day care centres are environments where children have proven to be more susceptible to acquiring IP. Methods and Principal Findings A cross-sectional study was carried to determine the prevalence of intestinal parasites in stool samples among children who attend to a day care centre in an urban area of Matanzas city, Cuba, from March to June 2012. 104 children under five years old were included on the study after informed consent form was signed by parents or legal guardians. Three fresh faecal samples were collected from each child in different days and were examined by direct wet mount, formalin-ether, and Kato- Katz techniques. Data relating to demography, socioeconomic status, source of drinking water, and personal hygiene habits were also collected using a standardized questionnaire. In total, 71.1% of children harbored at least one type of intestinal parasite and 47 (45.2%) were infected by more than one species. Giardia duodenalis and Blastocystis sp. were the most common parasites found, with prevalence rates of 54.8% and 38.5% respectively. Conclusions Despite public health campaigns, improvement in the level of education, and the availability of and access to medical services in Cuba infections by intestinal protozoan is high in this centre. Almost nothing is published regarding intestinal parasites in Matanzas province during the last 40 years so this work could also be the initial point to carry out other studies to clarify the IP status in this region. PMID:23236493

Human behaviour and the epidemiology of parasitic zoonoses.

PubMed

Macpherson, Calum N L

2005-10-01

The behaviour of Homo sapiens has a pivotal role to play in the macro and microepidemiology of emerging or re-emerging parasitic zoonoses. Changing demographics and the concomitant alterations to the environment, climate, technology, land use and changes in human behavior, converge to favour the emergence and spread of parasitic zoonoses. The recent unprecedented movements of people, their animals and their parasites around the world, introduce and mix genes, cultural preferences, customs, and behavioral patterns. The increasing proclivity for eating meat, fish, crabs, shrimp, molluscs raw, undercooked, smoked, pickled or dried facilitates a number of protozoan (Toxoplasma), trematode (Fasciola sp., Paragonimus spp., Clonorchis sp., Opisthorchis spp., Heterophyes sp., Metagonimus sp., Echinostoma spp., Nanophyetus sp.) cestode (Taenia spp, Diphyllobothrum sp.) and nematode (Trichinella spp., Capillaria spp., Gnathostoma spp., Anisakis sp., Parastrongylus spp.) caused zoonoses. The increasing world population and the inability to keep pace with the provision of adequate sanitation and clean, safe drinking water, has led to an increased importance of waterborne zoonoses, such as those caused by Giardia, Cryptosporidium and Toxoplasma. Our close relationship with and the numerous uses to which we put companion animals and their ubiquitous distribution has resulted in dogs and cats unwitting participation in sharing over 60 parasite species including: Giardia, Cryptosporidium, Toxoplasma, most foodborne trematode species, Diphyllobothrum, Echinococcus spp., Ancylostoma and Toxocara. Changing human behaviour through education, to encourage the proper cooking of food, which may have cultural and social significance, will remain as challenging as controlling stray and feral pet populations, improving hygiene levels and the provision of safe drinking water and the proper use of sanctuary facilities. Long pre-patent periods and the normally insidious sub-clinical nature of most zoonoses makes advice requiring behavioural change for their control a difficult task. Our clearer understanding of the heterogeneity of susceptibility to infection, the complex genetic variations of people and parasite species and the development of molecular epidemiological tools is shedding more light on transmission routes and the spectrum of disease that is observed. Improved and new serological, molecular and imaging diagnostic tests and the development of broad spectrum chemotherapeutic agents has led to the attenuation of morbidity and mortality due to parasitic zoonoses in economically advantaged regions. Such advancements, in partnership with supportive behavioural change, has the potential for a sustainable global reduction in the burden of ill health due to parasitic zoonoses. Whether this will materialise is a challenge for us all.

ANTIOXIDANT ENZYMES, POTENTIAL VIRULENT FACTORS, IN DIFFERENT STRAINS OF THE OYSTER PROTOZOAN PARASITE, PERKINSUS MARINUS

EPA Science Inventory

The oyster protozoan parasite, Perkinsus marinus, is one of the two important parasites causing severe mortality in the eastern oysters (Crassostrea virginica) on the US east coast. Our recent study suggests that P. marinus cells and its extracellular products (ECP) could scaveng...

Comparative analysis of the 5S rRNA and its associated proteins reveals unique primitive rather than parasitic features in Giardia lamblia.

PubMed

Feng, Jin-Mei; Sun, Jun; Xin, De-Dong; Wen, Jian-Fan

2012-01-01

5S rRNA is a highly conserved ribosomal component. Eukaryotic 5S rRNA and its associated proteins (5S rRNA system) have become very well understood. Giardia lamblia was thought by some researchers to be the most primitive extant eukaryote while others considered it a highly evolved parasite. Previous reports have indicated that some aspects of its 5S rRNA system are simpler than that of common eukaryotes. We here explore whether this is true to its entire system, and whether this simplicity is a primitive or parasitic feature. By collecting and confirming pre-existing data and identifying new data, we obtained almost complete datasets of the system of three isolates of G. lamblia, two other parasitic excavates (Trichomonas vaginalis, Trypanosoma cruzi), and one free-living one (Naegleria gruberi). After comprehensively comparing each aspect of the system among these excavates and also with those of archaea and common eukaryotes, we found all the three Giardia isolates to harbor a same simplified 5S rRNA system, which is not only much simpler than that of common eukaryotes but also the simplest one among those of these excavates, and is surprisingly very similar to that of archaea; we also found among these excavates the system in parasitic species is not necessarily simpler than that in free-living species, conversely, the system of free-living species is even simpler in some respects than those of parasitic ones. The simplicity of Giardia 5S rRNA system should be considered a primitive rather than parasitically-degenerated feature. Therefore, Giardia 5S rRNA system might be a primitive system that is intermediate between that of archaea and the common eukaryotic model system, and it may reflect the evolutionary history of the eukaryotic 5S rRNA system from the archaeal form. Our results also imply G. lamblia might be a primitive eukaryote with secondary parasitically-degenerated features.

Cryptosporidium and Giardia in Africa: current and future challenges.

PubMed

Squire, Sylvia Afriyie; Ryan, Una

2017-04-20

Cryptosporidium and Giardia are important causes of diarrhoeal illness. Adequate knowledge of the molecular diversity and geographical distribution of these parasites and the environmental and climatic variables that influence their prevalence is important for effective control of infection in at-risk populations, yet relatively little is known about the epidemiology of these parasites in Africa. Cryptosporidium is associated with moderate to severe diarrhoea and increased mortality in African countries and both parasites negatively affect child growth and development. Malnutrition and HIV status are also important contributors to the prevalence of Cryptosporidium and Giardia in African countries. Molecular typing of both parasites in humans, domestic animals and wildlife to date indicates a complex picture of both anthroponotic, zoonotic and spill-back transmission cycles that requires further investigation. For Cryptosporidium, the only available drug (nitazoxanide) is ineffective in HIV and malnourished individuals and therefore more effective drugs are a high priority. Several classes of drugs with good efficacy exist for Giardia, but dosing regimens are suboptimal and emerging resistance threatens clinical utility. Climate change and population growth are also predicted to increase both malnutrition and the prevalence of these parasites in water sources. Dedicated and co-ordinated commitments from African governments involving "One Health" initiatives with multidisciplinary teams of veterinarians, medical workers, relevant government authorities, and public health specialists working together are essential to control and prevent the burden of disease caused by these parasites.

Cryptosporidium spp. and Giardia duodenalis as pathogenic contaminants of water in Galicia, Spain: the need for safe drinking water.

PubMed

Castro-Hermida, José Antonio; González-Warleta, Marta; Mezo, Mercedes

2015-01-01

The objectives of this cross-sectional study were to detect the presence of Cryptosporidium spp. and Giardia duodenalis in drinking water treatments plants (DWTPs) in Galicia (NW Spain) and to identify which species and genotype of these pathogenic protozoans are present in the water. Samples of untreated water (surface or ground water sources) and of treated drinking water (in total, 254 samples) were collected from 127 DWTPs and analysed by an immunofluorescence antibody test (IFAT) and by PCR. Considering the untreated water samples, Cryptosporidium spp. were detected in 69 samples (54.3%) by IFAT, and DNA of this parasite was detected in 57 samples (44.8%) by PCR, whereas G. duodenalis was detected in 76 samples (59.8%) by IFAT and in 56 samples (44.0%) by PCR. Considering the treated drinking water samples, Cryptosporidium spp. was detected in 52 samples (40.9%) by IFAT, and the parasite DNA was detected in 51 samples (40.1%) by PCR, whereas G. duodenalis was detected in 58 samples (45.6%) by IFAT and in 43 samples (33.8%) by PCR. The percentage viability of the (oo)cysts ranged between 90.0% and 95.0% in all samples analysed. Cryptosporidium andersoni, C. hominis, C. parvum and assemblages A-I, A-II, E of G. duodenalis were identified. The results indicate that Cryptosporidium spp. and G. duodenalis are widespread in the environment and that DWTPs are largely ineffective in reducing/inactivating these pathogens in drinking water destined for human and animal consumption in Galicia. In conclusion, the findings suggest the need for better monitoring of water quality and identification of sources of contamination. Copyright © 2014 Elsevier GmbH. All rights reserved.

Infection rate and genetic diversity of Giardia duodenalis in pet and stray dogs in Henan Province, China.

PubMed

Qi, Meng; Dong, Haiju; Wang, Rongjun; Li, Junqiang; Zhao, Jinfeng; Zhang, Longxian; Luo, Jianxun

2016-04-01

Giardia duodenalis is an important protozoan parasite that is known to be zoonotic. To assess the potential zoonotic transmission of giardiasis from dogs and to identify genetic diversity of G. duodenalis in dog populations, we examined the infection rate and genotypes of G. duodenalis in both pet dogs (from pet dog farms, pet shops, pet hospitals, pet markets) and stray dogs of different ages in Henan Province, China. A total of 940 fresh fecal specimens were collected from 2007 to 2013 in Henan Province. The overall infection rate of G. duodenalis was 14.3% (134/940) as determined by microscopy, with the highest infection rate (17.3%) observed in dogs from shelters. Young dogs were more likely to be infected with G. duodenalis than adult dogs, and G. duodenalis cysts were found more frequently in diarrheic dogs. All G. duodenalis-positive isolates were characterized at the triose phosphate isomerase (tpi), glutamate dehydrogenase (gdh), and β-giardin (bg) loci, and 37, 51, and 48 sequences were obtained, respectively. The dog-specific assemblages C and D were identified using multi-locus sequence analysis. Six novel sequences of the tpi locus, one novel sequence of the gdh locus and two novel sequences of the bg locus were detected among the G. duodenalis assemblage C isolates, while two novel sequences of the gdh locus were found among the G. duodenalis assemblage D isolates. Our data indicate that G. duodenalis is a common parasite and cause of diarrheal disease in dogs in Henan Province. However, there was no evidence for zoonotic G. duodenalis assemblages in the study population. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

First report of Toxoplasma gondii sporulated oocysts and Giardia duodenalis in commercial green-lipped mussels (Perna canaliculus) in New Zealand.

PubMed

Coupe, Alicia; Howe, Laryssa; Burrows, Elizabeth; Sine, Abigail; Pita, Anthony; Velathanthiri, Niluka; Vallée, Emilie; Hayman, David; Shapiro, Karen; Roe, Wendi D

2018-05-01

Pollution of marine ecosystems with the protozoan parasites Toxoplasma gondii, Cryptosporidium spp. and Giardia duodenalis can be studied using bivalve shellfish as biosentinels. Although evidence suggests that these parasites are present in New Zealand coastal waters, the extent of protozoal pollution has not been investigated. This study used optimised molecular methods to detect the presence of Cryptosporidium spp., G. duodenalis and T. gondii in commercially sourced green-lipped mussel (Perna canaliculus), an endemic species found throughout coastal New Zealand. A nested polymerase chain reaction was validated for detection of T. gondii DNA and applied to 104 commercially sourced mussels. Thirteen mussels were positive for T. gondii DNA with an estimated true prevalence of 16.4% using Bayesian statistics, and the presence of T. gondii in mussels was significantly associated with collection during the summer compared with that in the winter (P = 0.003). Consumption of contaminated shellfish may also pose a health risk for humans and marine wildlife. As only sporulated T. gondii oocysts can be infectious, a reverse transcriptase-polymerase chain reaction was used to confirm presence of a sporozoite-specific marker (SporoSAG), detected in four mussels. G. duodenalis assemblage B, known to be pathogenic in humans, was also discovered in 1% mussels, tested by polymerase chain reaction (n = 90). Cryptosporidium spp. was not detected in the sampled mussel haemolymph. Results suggest that New Zealand may have high levels of coastal contamination with T. gondii, particularly in summer months, and that naturally exposed mussels can ingest and retain sporulated oocysts, further establishing shellfish consumption as a health concern.

Diagnosis of AIDS-Related Intestinal Parasites

DTIC Science & Technology

1989-01-20

other intestinal parasites: Giardia lamblia (65), Endolimax nana (35), Entamoeba coli (33), Chilomastix mesnili (25), Ascaris lumbricoides (8...likely at risk for infection. ELISA Testing for Entamoeba histolytica, Giardia lamblia, Cryptosporidium 7. Taylor DN, Houston R, Shlim DR, Echeverria P...Assn 260:1245-1248, 1988. Significance: ELISA testing for Entamoeba histolytica antigen in fecal specimens is a viable alternative to traditional

[Occurrence of Giardia species and genotypes in humans and animals in Wielkopolska region, Poland].

PubMed

Solarczyk, Piotr

2009-01-01

Giardia is the most common intestinal protozoan parasite found in humans and animals worldwide. Although it has been known for three hundred years, the nomenclature, taxonomy, host specificity, and pathogenicity of Giardia still arouse numerous controversies and ambiguities. Giardia is classified into six species, that are characterised by various ranges of hosts. The most dubious species is G. intestinalis, which includes a dozen or so genotypes, and only two of them (genotype A and B) have wide ranges of hosts, including humans. Moreover, in some genotype assemblages of G. intestinalis certain subgenotypes were distinguished and it was proven that in the same host species various subgenotypes of this parasite may occur. Bearing in mind the significant genetic heterogeneity of G. intestinalis and the fact that various genotypes and subgenotypes of this parasite are characterised by the broad or narrow host specificity, the data concerning the frequency of giardiosis occurrence are insufficient. It is necessary to use molecular biology techniques in order to define the genotype and/or the subgenotype of G. intestinalis that are found in humans and in certain animal species. Furthermore, since more and more pieces of evidence connected with a possibility of the sexual recombination of Giardia are gathered, it is unknown if genotypes and subgenotypes of this parasite are stable in time. The aim of this thesis was to define the frequency of Giardia occurrence in humans and animals in Wielkopolska region, to identify species and genotypes of Giardia that occur in humans and animals, as well as to obtain an axenic culture of the chosen isolates of Giardia from animals and to compare the sequence of the beta-giardin gene fragment obtained from the DNA isolated from cysts and trophozoites in order to check if the axenisation of G. intestinalis leads to the selection of genotypes or if Giardia genotypes are stable in time. Altogether, 2183 faecal samples were examined for the presence of Giardia cysts; 447 faecal samples were taken from 232 persons coming from 5 cities situated in Wielkopolska, and 1736 faecal samples were obtained from 123 animal species, including: 266 faecal samples from 113 species of animals kept in the Zoological Garden in Poznań, 1286 samples from 4 species of breeding animals, 118 samples from dogs, and 66 samples from 5 species of wild animals. Faecal samples were taken from animals coming from 25 places in Wielkopolska. Moreover, seven isolates of G. intestinalis were used in the studies, which were obtained from various species of hosts and kept in an axenic in vitro culture. Microscopic, molecular and bio-informative methods were used in the studies. From each faecal sample fresh smears were made in a 0.6% solution of physiological salt and in Lugol's solution, as well as a permanent smear stained with trichrome was made. Moreover, the following molecular techniques were implemented in the studies: DNA extraction and purification, the PCR technique (two molecular markers), electrophoresis and visualisation of PCR products, and sequencing. A fragment of the beta-giardin gene was used as a molecular marker in order to define the genotype and subgenotype of Giardia. Only in the case of genotyping of two Giardia isolates obtained from Peromyscus eremicus another molecular marker (SSU rRNA)was additionally used. Some widely available computer programmes (Chromas, CAP 3, BioEdit, BLASTn, MEGA version 4.0) were utilised in the analysis of the sequence of the beta-giardin gene fragment and in the phylogenetic analysis. The culture of Giardia trophozoites was established to compare the sequence of the partial beta-giardin gene from cysts and trophozoites. Concentration and purification of Giardia cysts in the saccharose gradient, and the excystation technique were applied in the studies to obtaining an axenic in vitro culture. In this study, Giardia cysts were found in 12 faecal samples obtained from 3 persons and 5 animal species. Giardia cysts were found only in faecal samples from humans living in Poznań and the samples obtained from animals coming from Poznań and around Puszczykowo. The highest frequency of infection was stated in domestic animals (2.5%) and in animals kept in the Zoological Garden (2.0%), whereas a slightly lower frequency was noticed in wild animals (1.5%) and in humans (1.3%). No Giardia cysts were found in the faecal samples collected from breeding animals. Two new species of Giardia hosts were identified, namely Rhinella marina and Peromyscus eremicus; however, due to a minimal amount of faecal samples supplied for the study it was impossible to define the species and genotype of this parasite. PCR products (the partial of beta-giardin gene) were obtained in seven faecal samples out of the ten studied, including three samples from people and four faecal samples derived from three animal species (i.e. dog, tamandua, red deer). Moreover, molecular characterization of seven Giardia isolates from three persons and four animal species (red-bellied monkey, silver marmoset, Thomson's gazelle, and sheep) kept in an axenic in vitro culture was performed. Based on the beta-giardin sequence fragment analysis, four assemblages of G. intestinalis genotypes were identified (A, B, C and D). In humans, A and B G. intestinalis genotypes and three subgenotypes, including a cosmopolitan subgenotype A2 and two new subgenotypes A and B were detected. Furthermore, four G. intestinalis genotypes were found in animals, including three genotypes which are non-infectious to humans, namely: genotypes C and D in dogs and a cervids-specific genotype A in red deer (Cervus elaphus), which indicate that these animals do not constitute the source of infection to humans. On the other hand, in a tamandua from the Zoological Garden in Poznań a new subgenotype B of G. intestinalis was identified, which due to a close relationship with Giardia isolates obtained from humans is potentially infectious to man. In none of the studied faecal samples a mixed infection of Giardia was found. To date, nine sequences of the partial beta-giardin gene have been deposited in the National Center for Biotechnology Information (NCBI), including two sequences of Giardia isolates obtained from humans (GenBank accession numbers FJ009207, FJ009208), three sequences of isolate obtained from red deer (GenBank accession numbers EU621373, EU626198, EU216429), two sequences of both Giardia isolates obtained from dogs (GenBank accession numbers FJ009205, FJ009206), and the single sequences obtained from tamandua (GenBank accession number FJ009209) and from Thomson's gazelle (GenBank accession number EU626199). According to the literature, an axenic in vitro culture of G. intestinalis was obtained from a red deer for the first time. Based on the analysis of the sequence of the beta-giardin gene fragment obtained from the DNA isolated from cysts and trophozoites it was proven that the red deer was infected with a single population of Giardia and that during the axenisation of the culture no mutation in the DNA of the parasite's trophozoites took place. Probably the time distance that the DNA was isolated from the trophozoites kept in the culture was too short to cause the mutation. This suggestion is confirmed by the results of the genotyping of seven G. intestinalis isolates obtained from various host species and kept in an axenic in vitro culture for at least a number of years. Based on the molecular characteristics it was stated that all the studied isolates from the axenic culture were identical and belonged to the same assemblage B. The comparision with the sequences from GenBank database revealed that all mentioned isolates were 99% similar to the sequence of Giardia Nij5 isolate obtained from a person from the Netherlands and characterised as genotype B1. Due to the sameness of the molecular marker sequences it seems improbable that the identical G. intestinalis genotype occurred in various time periods (the largest difference was 14 years) in humans and in a number of animal species in diverse areas of Wielkopolska region. Quite opposite, the long-term keeping of these isolates in the homogenous conditions of an axenic in vitro culture leads to the selection of a genotype or proves the instability of genotypes of this parasite. Long-term studies need to be conducted in order to verify these hypothesis. Their results will have a key meaning in explaining the genetic structure of the Giardia population and in understanding the molecular epidemiology of giardiosis.

Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries

PubMed Central

Tussupova, Kamshat; Berndtsson, Ronny; Sharapatova, Kulyash

2018-01-01

Improved water, sanitation and hygiene (WASH) are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people’s health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries. PMID:29534511

Cryptosporidium parvum Among Coprolites from La Cueva de los Muertos Chiquitos (600-800 CE), Rio Zape Valley, Durango, Mexico.

PubMed

Morrow, Johnica J; Reinhard, Karl J

2016-08-01

:  In the present study, 90 coprolites from La Cueva de los Muertos Chiquitos (CMC) were subjected to enzyme-linked immunosorbent assay (ELISA) tests for 3 diarrhea-inducing protozoan parasites, Entamoeba histolytica , Giardia duodenalis , and Cryptosporidium parvum , to determine whether these parasites were present among the people who utilized this cave 1,200-1,400 yr ago. These people, the Loma San Gabriel, developed as a culture out of the Archaic Los Caracoles population and lived throughout much of present-day Durango and Zacatecas in Mexico. The Loma San Gabriel persisted through a mixed subsistence strategy of hunting-gathering and agricultural production. The results of ELISA testing were negative for both E. histolytica and G. duodenalis across all coprolites. A total of 66/90 (∼73% prevalence) coprolites tested positive or likely positive for C. parvum . The high prevalence of C. parvum among CMC coprolites contributes to our growing knowledge of the pathoecology among the Loma San Gabriel who utilized CMC. Herein, we report the successful recovery of C. parvum coproantigens from prehistoric coprolites. The recovery of these coproantigens demonstrates the existence of C. parvum in Mesoamerica before European contact in the 1400s.

Protozoan Parasites in Drinking Water: A System Approach for Improved Water, Sanitation and Hygiene in Developing Countries.

PubMed

Omarova, Alua; Tussupova, Kamshat; Berndtsson, Ronny; Kalishev, Marat; Sharapatova, Kulyash

2018-03-12

Improved water, sanitation and hygiene (WASH) are significant in preventing diarrhea morbidity and mortality caused by protozoa in low- and middle-income countries. Due to the intimate and complex relationships between the different WASH components, it is often necessary to improve not just one but all of these components to have sustainable results. The objective of this paper was to review the current state of WASH-related health problems caused by parasitic protozoa by: giving an overview and classification of protozoa and their effect on people's health, discussing different ways to improve accessibility to safe drinking water, sanitation services and personal hygiene behavior; and suggesting an institutional approach to ensure improved WASH. The findings indicate that Giardia and Cryptosporidium are more often identified during waterborne or water-washed outbreaks and they are less sensitive than most of the bacteria and viruses to conventional drinking water and wastewater treatment methods. There are various institutions of control and prevention of water-related diseases caused by protozoa in developed countries. Unfortunately, the developing regions do not have comparable systems. Consequently, the institutional and systems approach to WASH is necessary in these countries.

Prevalence of intestinal parasites in companion dogs with diarrhea in Beijing, China, and genetic characteristics of Giardia and Cryptosporidium species.

PubMed

Yu, Zhongjia; Ruan, Yang; Zhou, Mengjie; Chen, Siyuan; Zhang, Yinxin; Wang, Liya; Zhu, Guan; Yu, Yonglan

2018-01-01

Companion animals including dogs are one of the important components in One Health. Parasites may cause not only diseases in pet animals but also many zoonotic diseases infecting humans. In this study, we performed a survey of intestinal parasites in fecal specimens (n = 485) collected from outpatient pet dogs with diarrhea in Beijing, China, for the entire year of 2015 by microscopic examination (all parasites) and SSU rRNA-based nested PCR detection (Giardia and Cryptosporidium). We observed a total of 124 (25.6%) parasite-positive specimens that contained one or more parasites, including Giardia duodenalis (12.8%), Cryptosporidium spp. (4.9%), Cystoisospora spp. (4.3%), trichomonads (4.3%), Toxocara canis (3.5%), Trichuris vulpis (0.6%), and Dipylidium caninum (0.2%). Among the 55 dog breeds, infection rates were significantly higher in border collies and bulldogs, but lower in poodles (p < 0.05). Risk factor analysis suggested that age was negatively correlated with the infection rate (p < 0.00001), while vaccination and deworming in the past 12 months could significantly reduce the parasite infections (p < 0.01). Among the 62 Giardia-positive specimens, 21 were successfully assigned into assemblages using glutamate dehydrogenase (gdh) and/or beta-giardin (bg) genes, including assemblage D (n = 15), C (n = 5), and F (n = 1). Among the 24 Cryptosporidium-positive specimens by SSU rRNA PCR, 20 PCR amplicons could be sequenced and identified as Cryptosporidium canis (n = 20). Collectively, this study indicates that parasites are a significant group of pathogens in companion dogs in Beijing, and companion dogs may potentially transmit certain zoonotic parasites to humans, particularly those with weak or weakened immunity.

Greater intensity and frequency of Cryptosporidium and Giardia oocyst shedding beyond the neonatal period is associated with reductions in growth, carcase weight and dressing efficiency in sheep.

PubMed

Jacobson, Caroline; Williams, Andrew; Yang, Rongchang; Ryan, Una; Carmichael, Ian; Campbell, Angus J; Gardner, Graham E

2016-09-15

Associations between intensity and frequency of Cryptosporidium and Giardia shedding with growth, carcase weight and dressing% were investigated using a longitudinal study of 1182 lambs on eight Australian farms. Live weight was recorded and faecal samples were collected on three sampling occasions; weaning (approximately 12 weeks of age), post-weaning (approximately 19 weeks) and pre-slaughter (approximately 29 weeks). Hot standard carcase weight (HSCW) and dressing% were measured at slaughter. Faecal samples were screened for presence and concentration of Cryptosporidium, Giardia and Haemonchus oocysts using a quantitative PCR. Trichostrongylid eggs were quantified with modified McMaster faecal worm egg count (WEC). Protozoan shedding intensity was categorised as high (above median oocyst concentration in positive sheep), low (below median oocyst concentration in positive sheep) or not detected. Shedding was also categorised for shedding type (no shedding, single Giardia infection, single Cryptosporidium infection, concurrent Giardia and Cryptosporidium infection) and lambs were categorised for frequency of shedding (shedding identified on 0, 1, 2 or 3 occasions). Associations of parasite shedding intensity category, shedding type, shedding frequency, WEC and Haemonchus status (positive or negative) with lamb production were assessed using general linear models (HSCW and dressing%) and linear mixed effects models (live weight). High Cryptosporidium parvum shedding was associated with lower live weight, ranging 2.31-4.52kg over the 3 sampling occasions. Cryptosporidium parvum shedding was associated with less HSCW in high (3.22kg less) and low (3.22kg less) shedding lambs post-weaning, and high (2.21kg less) and low (2.60kg less) shedding lambs pre-slaughter as well as lower dressing% (2.7% lower in high shedding lambs post-weaning). Cryptosporidium (all species) shedding pre-slaughter was associated with reduced dressing% in both high (1.25% lower) and low (1.21% lower) shedding lambs. Giardia shedding pre-slaughter was associated with 0.59kg less HSCW in high shedding lambs. Increased frequency of C. parvum and Giardia shedding in a specific animal (repeated detection) were associated with reduced HSCW and dressing%. Concurrent Giardia and Cryptosporidium shedding pre-slaughter was associated with reduced dressing%. No statistically significant main effects for either WEC (P>0.05) or Haemonchus status (P>0.05) were identified for any of the sheep meat productivity measures (live weight, HSCW and dressing%). The findings suggest naturally acquired Cryptosporidium and Giardia infections in grazing sheep are associated with depressed growth, carcase weight and dressing efficiency beyond the neonatal period in sheep representing a range of genetic backgrounds and different sheep production environments. Copyright © 2016 Elsevier B.V. All rights reserved.

Differences in staining intensities affect reported occurrences and concentrations of Giardia spp. in surface drinking water sources.

PubMed

Alderisio, K A; Villegas, L F; Ware, M W; McDonald, L A; Xiao, L; Villegas, E N

2017-12-01

USEPA Method 1623, or its equivalent, is currently used to monitor for protozoan contamination of surface drinking water sources worldwide. At least three approved staining kits used for detecting Cryptosporidium and Giardia are commercially available. This study focuses on understanding the differences among staining kits used for Method 1623. Merifluor and EasyStain labelling kits were used to monitor Cryptosporidium oocyst and Giardia cyst densities in New York City's raw surface water sources. In the year following a change to the approved staining kits for use with Method 1623, an anomaly was noted in the occurrence of Giardia cysts in New York City's raw surface water. Specifically, Merifluor-stained samples had higher Giardia cyst densities as compared with those stained with EasyStain. Side by side comparison revealed significantly lower fluorescence intensities of Giardia muris as compared with Giardia duodenalis cysts when labelled with EasyStain. This study showed very poor fluorescence intensity signals by EasyStain on G. muris cysts resulting in lower cyst counts, while Merifluor, with its broader Giardia cyst staining specificity, resulted in higher cyst counts, when using Methods 1623. These results suggest that detected Giardia cyst concentrations are dependent on the staining kits used, which can result in a more or less conservative estimation of occurrences and densities of zoonotic Giardia cysts by detecting a broader range of Giardia species/Assemblages. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Apo And Calcium-Bound Crystal Structures of Alpha-11 Giardin, An Unusual Annexin From 'Giardia Lamblia'

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pathuri, P.; Nguyen, E.T.; Svard, S.G.

2007-07-12

Alpha-11 giardin is a member of the multi-gene alpha-giardin family in the intestinal protozoan, Giardia lamblia. This gene family shares an ancestry with the annexin super family, whose common characteristic is calcium-dependent binding to membranes that contain acidic phospholipids. Several alpha giardins are highly expressed during parasite-induced diarrhea in humans. Despite being a member of a large family of proteins, little is known about the function and cellular localization of alpha-11 giardin, although giardins are often associated with the cytoskeleton. It has been shown that Giardia exhibits high levels of alpha-11 giardin mRNA transcript throughout its life cycle; however, constitutivemore » over-expression of this protein is lethal to the parasite. Determining the three-dimensional structure of an alpha-giardin is essential to identifying functional domains shared in the alpha-giardin family. Here we report the crystal structures of the apo and Ca{sup 2+}-bound forms of alpha-11 giardin, the first alpha giardin to be characterized structurally. Crystals of apo and Ca{sup 2+}-bound alpha-11 giardin diffracted to 1.1 angstroms and 2.93 angstroms, respectively. The crystal structure of selenium-substituted apo alpha-11 giardin reveals a planar array of four tandem repeats of predominantly {alpha}-helical domains, reminiscent of previously determined annexin structures, making this the highest-resolution structure of an annexin to date. The apo alpha-11 giardin structure also reveals a hydrophobic core formed between repeats I/IV and II/III, a region typically hydrophilic in other annexins. Surprisingly, the Ca{sup 2+}-bound structure contains only a single calcium ion, located in the DE loop of repeat I and coordinated differently from the two types of calcium sites observed in previous annexin structures. The apo and Ca{sup 2+}-bound alpha-11 giardin structures assume overall similar conformations; however, Ca2+-bound alpha-11 giardin crystallized in a lower-symmetry space group with four molecules in the asymmetric unit. Vesicle-binding studies suggest that alpha-11 giardin, unlike most other annexins, does not bind to vesicles composed of acidic phospholipids in a calcium-dependent manner.« less

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 infections may be an important cause of infertility. Given the widespread prevalence of parasitic protozoa diseases worldwide, we suggest further studies to better understanding of relationship between such infections and infertility.

Detection and multilocus genotyping of Giardia duodenalis in dogs in Sichuan province, China.

PubMed

Zhang, Yue; Zhong, Zhijun; Deng, Lei; Wang, Maoqing; Li, Wei; Gong, Chao; Fu, Hualin; Cao, Suizhong; Shi, Xianpeng; Wu, Kongju; Peng, Guangneng

2017-01-01

Giardia duodenalis (also known as G. intestinalis) is a flagellated protozoan that parasitizes the small intestine and is a common causal agent of zoonotic infections in humans and animals. To assess the genetic diversity and zoonotic transmission potential of G. duodenalis in stray dogs, 159 fecal specimens were collected from dogs in Chengdu, Yaan, and Leshan in Sichuan province, China. Of the 159 fecal samples from stray dogs, 18 (11.3%) were G. duodenalis-positive based on nested PCR amplification of the beta giardin (bg) gene, and the occurrence varied from 1.8% to 35% in different cities. Dog-specific assemblages C (n = 9) and D (n = 9) were identified. The glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi) genes of all bg-positive isolates were characterized. A total of 16 and 8 isolates were positive for the gdh and tpi genes, respectively. Two novel sequences of the bg locus were detected among genetic assemblage D isolates, and one novel gdh sequence and four novel tpi sequences were identified among genetic assemblage C isolates. Mixed infections of assemblages C and D were also detected. Assemblages A and B, which have high zoonotic potential, were not detected. Our results show that G. duodenalis is prevalent and a cause of diarrhea in dogs in Sichuan province, China. © Y. Zhang et al., published by EDP Sciences, 2017.

Giardia: a pathogen or commensal for children in high prevalence settings?

PubMed Central

Bartelt, Luther A.

2016-01-01

Purpose of review Giardia is a common intestinal parasite worldwide, and infection can be associated with clear and sometimes persistent symptomatology. However, in children in high prevalence settings, it is not associated with or is perhaps even protective against acute diarrhea, and the association with long-term outcomes has been difficult to discern. Recent findings Recent studies have made progress in helping us disentangle this apparent paradox. First, prospective, well-characterized cohort studies have added to the data on the association between Giardia and diarrhea in these settings and have further characterized associations between Giardia infection and nutrition, gut function, and growth. Second, animal models have further characterized the host response to Giardia and helped elucidate mechanisms by which Giardia could impair child development. Finally, new work has shed light on the heterogeneity of human Giardia strains, which may both explain discrepant findings in the literature and help guide higher-resolution analyses of this pathogen in the future. Summary The true clinical impact of endemic pediatric giardiasis remains unclear, but recent prospective studies have confirmed a high prevalence of persistent, subclinical Giardia infections and associated growth shortfalls. Integrating how nutritional, microbial, metabolic, and pathogen-strain variables influence these outcomes could sharpen delineations between pathogenic and potentially beneficial attributes of this enigmatic parasite. PMID:27479025

Giardia: a pathogen or commensal for children in high-prevalence settings?

PubMed

Bartelt, Luther A; Platts-Mills, James A

2016-10-01

Giardia is a common intestinal parasite worldwide, and infection can be associated with clear and sometimes persistent symptomatology. However, in children in high-prevalence settings, it is not associated with or is perhaps even protective against acute diarrhea, and the association with long-term outcomes has been difficult to discern. Recent studies have made progress in helping us disentangle this apparent paradox. First, prospective, well-characterized cohort studies have added to the data on the association between Giardia and diarrhea in these settings and have further characterized associations between Giardia infection and nutrition, gut function, and growth. Second, animal models have further characterized the host response to Giardia and helped elucidate mechanisms by which Giardia could impair child development. Finally, new work has shed light on the heterogeneity of human Giardia strains, which may both explain discrepant findings in the literature and help guide higher-resolution analyses of this pathogen in the future. The true clinical impact of endemic pediatric giardiasis remains unclear, but recent prospective studies have confirmed a high prevalence of persistent, subclinical Giardia infections and associated growth shortfalls. Integrating how nutritional, microbial, metabolic, and pathogen-strain variables influence these outcomes could sharpen delineations between pathogenic and potentially beneficial attributes of this enigmatic parasite.

Vaccination of domestic animals with a novel oral vaccine prevents Giardia infections, alleviates signs of giardiasis and reduces transmission to humans

PubMed Central

Serradell, Marianela C; Saura, Alicia; Rupil, Lucia L; Gargantini, Pablo R; Faya, Marcela I; Furlan, Paulina J; Lujan, Hugo D

2016-01-01

Giardia lamblia is a human intestinal parasite and one of the most frequent enteric pathogen of companion animals. Clinical manifestations of giardiasis, such as diarrhoea, anorexia, weight loss and lethargy, have been associated with Giardia infections in both domestic and farm animals. A few anti-parasitic drugs are routinely used to treat giardiasis, but re-infections are common and drug-resistant strains have already been reported. Unfortunately, efficient vaccines against Giardia are not available. Giardia undergoes antigenic variation; through this mechanism, parasites can avoid the host’s immune defenses, causing chronic infections and/or re-infections. Antigenic variation is characterised by a continuous switch in the expression of members of a homologous family of genes encoding surface antigens. In a previous report, we indicated that in Giardia, the mechanism responsible for the exchange of variant-specific surface proteins (VSPs) involves the RNA interference (RNAi) pathway. From a repertoire of ~200 VSP genes, only one is expressed on the surface of single trophozoites; however, RNAi machinery disruption generates trophozoites that express the complete VSP repertoire. We also demonstrated that gerbils orally immunised with VSPs isolated from these altered parasites showed high levels of protection. Here we tested this vaccine in cats and dogs, and found that it is highly efficient in preventing new infections and reducing chronic giardiasis in domestic animals both in experimental and natural infections. Remarkably, immunisation of dogs in a highly endemic area strongly decreased the percentage of infected children in the community, suggesting that this vaccine would block the zoonotic transmission of the disease. PMID:29263857

Gastrointestinal and ectoparasites from urban stray dogs in Fortaleza (Brazil): high infection risk for humans?

PubMed

Klimpel, Sven; Heukelbach, Jörg; Pothmann, David; Rückert, Sonja

2010-08-01

Dogs are important definite or reservoir hosts for zoonotic parasites. However, only few studies on the prevalence of intestinal parasites in urban areas in Brazil are available. We performed a comprehensive study on parasites of stray dogs in a Brazilian metropolitan area. We included 46 stray dogs caught in the urban areas of Fortaleza (northeast Brazil). After euthanization, dogs were autopsied. Ectoparasites were collected, and the intestinal content of dogs were examined for the presence of parasites. Faecal samples were collected and analysed using merthiolate iodine formaldehyde concentration method. A total of nine different parasite species were found, including five endoparasite (one protozoan, one cestode and three nematode species) and four ectoparasite species (two flea, one louse and one tick species). In the intestinal content, 3,162 specimens of four helminth species were found: Ancylostoma caninum (prevalence, 95.7%), Dipylidium caninum (45.7%), Toxocara canis (8.7%) and Trichuris vulpis (4.3%). A total of 394 ectoparasite specimens were identified, including Rhipicephalus sanguineus (prevalence, 100.0%), Heterodoxus spiniger (67.4%), Ctenocephalides canis (39.1%) and Ctenocephalides felis (17.4%). In the faeces, intestinal parasites were detected in 38 stray dogs (82.6%), including oocysts of Giardia sp. (2.2%) and eggs of the nematode A. caninum (82.6%). Neither eggs nor larval stages of D. caninum, T. canis or T. vulpis were detected in dog faeces. Sensitivity of faecal examination for A. caninum was 86.4% (95% confidence interval, 72.0-94.3) but zero percentage for the other intestinal helminth species. Our data show that stray dogs in northeast Brazil carry a multitude of zoonotic ecto- and endoparasites, posing a considerable risk for humans. With the exception of A. caninum, sensitivity of faecal examination was negligible.

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.

Prevalence of selected zoonotic and vector-borne agents in dogs and cats in Costa Rica.

PubMed

Scorza, Andrea V; Duncan, Colleen; Miles, Laura; Lappin, Michael R

2011-12-29

To estimate the prevalence of enteric parasites and selected vector-borne agents of dogs and cats in San Isidro de El General, Costa Rica, fecal and serum samples were collected from animals voluntarily undergoing sterilization. Each fecal sample was examined for parasites by microscopic examination after fecal flotation and for Giardia and Cryptosporidium using an immunofluorescence assay (IFA). Giardia and Cryptosporidium IFA positive samples were genotyped after PCR amplification of specific DNA if possible. The seroprevalence rates for the vector-borne agents (Dirofilaria immitis, Borrelia burgdorferi, Ehrlichia canis, and Anaplasma phagocytophilum) were estimated based on results from a commercially available ELISA. Enteric parasites were detected in samples from 75% of the dogs; Ancylostoma caninum, Trichuris vulpis, Giardia, and Toxocara canis were detected. Of the cats, 67.5% harbored Giardia spp., Cryptosporidium spp., Ancylostoma tubaeforme, or Toxocara cati. Both Cryptosporidium spp. isolates that could be sequenced were Cryptosporidium parvum (one dog isolate and one cat isolate). Of the Giardia spp. isolates that were successfully sequenced, the 2 cat isolates were assemblage A and the 2 dog isolates were assemblage D. D. immitis antigen and E. canis antibodies were identified in 2.3% and 3.5% of the serum samples, respectively. The prevalence of enteric zoonotic parasites in San Isidro de El General in Costa Rica is high in companion animals and this information should be used to mitigate public health risks. Copyright © 2011. Published by Elsevier B.V.

A survey for potentially zoonotic gastrointestinal parasites in domestic cavies in Cameroon (Central Africa).

PubMed

Meutchieye, Felix; Kouam, Marc K; Miegoué, Emile; Nguafack, Terence T; Tchoumboué, Joseph; Téguia, Alexis; Théodoropoulos, Georgios

2017-06-26

Farm animals are usually suspected to transmit infections to humans. Domestic cavies (Cavia porcellus) are hosts to a variety of pathogens, some of which are zoonotic. Several parasites including the protozoa Giardia spp. and Cryptosporidium spp. may be causative agents of gastrointestinal disorders in domestic cavies and humans. The aim of the study was to investigate the occurrence of potentially zoonotic protozoa as well as any potential zoonotic gastrointestinal parasite in domestic cavies raised under a semi extensive system in the rural areas of Cameroon. Giardia/Cryptosporidium antigens were detected in 12.90% of cavies. Helminthe eggs were found in 1.52% of animals. The prevalence of Paraspidodera uncinata, Heligmosomoides polygyrus (also known as Nematospiroides dubius) and Trichuris sp. was 1% (4/397), 0.3% (1/397), and 0.3% (1/397), respectively. Presence of Giardia/Cryptosporidium was unrelated to the occurrence of diarrhea, as none of the positive samples was from a diarrheic individual. Domestic cavies are hosts of Giardia/Cryptosporidium and appear as potential source of human giardiasis, cryptosporidiosis and infection with H. polygyrus in Cameroon. In keeping with the One Health Initiative, veterinarians and medical doctors should collaborate to address the problem of Giardia and Cryptosporidium infection in cavies and cavy breeders both in Cameroon and other countries with a similar cavy breeding system. Follow-up studies are required to further taxonomically characterize these cavy parasites and to determine their routes of transmission to humans.

Recent Advances in Human Protozoan Parasites of Gastrointestinal Tract

DTIC Science & Technology

1987-02-01

biology of the parasites, the epidemiology , diagnosis, pathogenesis and treatment. Furthermore, protozoan parasites formerly considered of no human...gastrointestinal tract and the epidemiology and pathogenesis of the diseases they cause; in most cases only papers published since 1980 were included. FLAGELLATES...are diarrhea, abdominal pain and occasionally anal pruritis. There have also been several reports of eosinophilia associated with D. fragilis

Comparative Analysis of the 5S rRNA and Its Associated Proteins Reveals Unique Primitive Rather Than Parasitic Features in Giardia lamblia

PubMed Central

Xin, De-Dong; Wen, Jian-Fan

2012-01-01

Background 5S rRNA is a highly conserved ribosomal component. Eukaryotic 5S rRNA and its associated proteins (5S rRNA system) have become very well understood. Giardia lamblia was thought by some researchers to be the most primitive extant eukaryote while others considered it a highly evolved parasite. Previous reports have indicated that some aspects of its 5S rRNA system are simpler than that of common eukaryotes. We here explore whether this is true to its entire system, and whether this simplicity is a primitive or parasitic feature. Methodology/Principal Findings By collecting and confirming pre-existing data and identifying new data, we obtained almost complete datasets of the system of three isolates of G. lamblia, two other parasitic excavates (Trichomonas vaginalis, Trypanosoma cruzi), and one free-living one (Naegleria gruberi). After comprehensively comparing each aspect of the system among these excavates and also with those of archaea and common eukaryotes, we found all the three Giardia isolates to harbor a same simplified 5S rRNA system, which is not only much simpler than that of common eukaryotes but also the simplest one among those of these excavates, and is surprisingly very similar to that of archaea; we also found among these excavates the system in parasitic species is not necessarily simpler than that in free-living species, conversely, the system of free-living species is even simpler in some respects than those of parasitic ones. Conclusion/Significance The simplicity of Giardia 5S rRNA system should be considered a primitive rather than parasitically-degenerated feature. Therefore, Giardia 5S rRNA system might be a primitive system that is intermediate between that of archaea and the common eukaryotic model system, and it may reflect the evolutionary history of the eukaryotic 5S rRNA system from the archaeal form. Our results also imply G. lamblia might be a primitive eukaryote with secondary parasitically-degenerated features. PMID:22685540

Seasonal and biogeographical patterns of gastrointestinal parasites in large carnivores: wolves in a coastal archipelago.

PubMed

Bryan, Heather M; Darimont, Chris T; Hill, Janet E; Paquet, Paul C; Thompson, R C Andrew; Wagner, Brent; Smits, Judit E G

2012-05-01

Parasites are increasingly recognized for their profound influences on individual, population and ecosystem health. We provide the first report of gastrointestinal parasites in gray wolves from the central and north coasts of British Columbia, Canada. Across 60 000 km(2), wolf feces were collected from 34 packs in 2005-2008. At a smaller spatial scale (3300 km(2)), 8 packs were sampled in spring and autumn. Parasite eggs, larvae, and cysts were identified using standard flotation techniques and morphology. A subset of samples was analysed by PCR and sequencing to identify tapeworm eggs (n=9) and Giardia cysts (n=14). We detected ≥14 parasite taxa in 1558 fecal samples. Sarcocystis sporocysts occurred most frequently in feces (43·7%), followed by taeniid eggs (23·9%), Diphyllobothrium eggs (9·1%), Giardia cysts (6·8%), Toxocara canis eggs (2·1%), and Cryptosporidium oocysts (1·7%). Other parasites occurred in ≤1% of feces. Genetic analyses revealed Echinococcus canadensis strains G8 and G10, Taenia ovis krabbei, Diphyllobothrium nehonkaiense, and Giardia duodenalis assemblages A and B. Parasite prevalence differed between seasons and island/mainland sites. Patterns in parasite prevalence reflect seasonal and spatial resource use by wolves and wolf-salmon associations. These data provide a unique, extensive and solid baseline for monitoring parasite community structure in relation to environmental change.

THE INCREASING NEED FOR SURVEILLANCE: WATER SOURCES AND ENVIRONMENTAL FACTORS

EPA Science Inventory

The outbreaks of giardiosis in the 1980's and the outbreak of cryptosporidiosis in Milwaukee, have demonstrated the susceptibility of public water supplies to contamination with protozoan parasites. Many protozoan parasites are resistant to the levels of residual disinfectant re...

Prevalence of endoparasitic infection in children and its relation with cholera prevention efforts in Mexico.

PubMed

Faulkner, Charles T; Garcia, Benito Borrego; Logan, Michael H; New, John C; Patton, Sharon

2003-07-01

To investigate whether increased knowledge and use of public health measures promoted for cholera prevention is reflected in lower prevalence of parasitic infection in households in a community in the state of Tamaulipas, Mexico, that is close to the border with the United States of America. Between 1994 and 1997, fecal samples from 438 children were collected through convenience sampling and then examined for helminth eggs/larvae and protozoan cysts as biologic indicators of household compliance with recommended cholera prevention measures. The suggested measures were to wash hands before meals and after defecation, to drink purified water, to wash fruits and vegetables, and to eat well-cooked food. In addition, information on the knowledge of and the use of cholera preventive measures was collected by interviews with adult informants in 252 households (186 of those households also provided a fecal sample for analysis). Parasitic infections occurred in 131 of the 438 children (30%), who resided in 79 of the 186 households (42%) that provided fecal samples. Giardia lamblia accounted for 12.5% of all infections. Infections with Hymenolepis nana, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Ancylostoma/Necator, Strongyloides stercoralis, Entamoeba coli, Entamoeba hartmanni, Entamoeba histolytica, Endolimax nana, and Iodamoeba bütschlii were also noted. Infected children were older and more often had an infected sibling. Households with three or more children were also more likely to have an infected child. The primary caregivers in the households where at least one child had a parasitic infection were distinguished by their inability to list at least three cholera prevention measures from memory. The 42% household prevalence of parasitic infection was relatively high and indicates that some residents of this community may not have fully embraced the public health education efforts promoted for prevention of cholera. The occurrence of nonpathogenic protozoan parasites such as Endolimax nana, Entamoeba coli, Entamoeba hartmanni, and I. bütschlii are important bioindicators for the persistence of unhygienic behaviors that increase the risk of cholera and other infectious diseases dependent on fecal-oral transmission. Information obtained by similar studies can be useful for monitoring compliance with community health and hygiene programs and may indicate the need to intensify educational efforts for the prevention of diarrhea associated with enteric pathogens that cannot be controlled by drugs alone.

Giardia and Cryptosporidium in cetaceans on the European Atlantic coast.

PubMed

Reboredo-Fernández, Aurora; Ares-Mazás, Elvira; Martínez-Cedeira, José A; Romero-Suances, Rafael; Cacciò, Simone M; Gómez-Couso, Hipólito

2015-02-01

The occurrence of Giardia and Cryptosporidium was investigated in cetacean specimens stranded on the northwestern coast of Spain (European Atlantic coast) by analysis of 65 samples of large intestine from eight species. The parasites were identified by direct immunofluorescence antibody test (IFAT) and by PCR amplification of the β-giardin gene, the ITS1-5.8S-ITS2 region and the SSU-rDNA gene of Giardia and the SSU-rDNA gene of Cryptosporidium. Giardia and Cryptosporidium were detected in 7 (10.8 %) and 9 samples (13.8 %), respectively. In two samples, co-infection with both parasites was observed. Giardia duodenalis assemblages A, C, D and F, and Cryptosporidium parvum were identified. This is the first report of G. duodenalis in Balaenoptera acutorostrata, Kogia breviceps and Stenella coeruleoalba and also the first report of Cryptosporidium sp. in B. acutorostrata and of C. parvum in S. coeruleoalba and Tursiops truncatus. These results extend the known host range of these waterborne enteroparasites.

Comparative Evaluation of Three Methods (Microscopic Examination, Direct Fluorescent Antibody Assay, and Immunochromatographic Method) for the Diagnosis of Giardia intestinalis From Stool Specimens.

PubMed

Karadam, Senem Yaman; Ertuğ, Sema; Ertabaklar, Hatice

2016-03-01

The aim of this study was to compare direct microscopic examination, direct fluorescent antibody assay (DFA), and the immunochromatographic method (IK) and identify the best suitable method for the diagnosis of Giardia intestinalis. In this study, 25 stool samples that had been diagnosed as being infected with G. intestinalis using the native-Lugol and/or formol-ethyl acetate concentration method and 25 non-parasite-infected samples (the control group) were examined. After microscopic examination of stools, they were kept at -20°C for examination using DFA and IK. Stool samples were studied using DFA (CeLLabs, Crypto/Giardia-Cel IF) and IK (RIDA QUICK, Cryptosporidium/Giardia Combi Dipstick), as per the manufacturers' instructions. In our study, using the DFA method, parasites were detected in all 25 stool samples in which G. intestinalis was diagnosed by direct microscopic examination. Using the IK method, a particular band indicative of the parasite was detected in 24 samples. No parasites were detected in all 25 samples in the control group. Thus, when direct microscopic examination is taken as reference, the senstivity and specificity of DFA for the diagnosis of G. intestinalis were found to be 100% each, while those of IK were found to be 96% and 100%, respectively.

Molecular diagnosis of protozoan parasites by Recombinase Polymerase Amplification.

PubMed

Castellanos-Gonzalez, A; White, A C; Melby, P; Travi, B

2018-06-01

Infections caused by protozoan parasites affect millions of people around the world. Traditionally, diagnosis was made by microscopy, which is insensitive and in some cases not specific. Molecular methods are highly sensitive and specific, but equipment costs and personnel training limit its availability only to specialized centers, usually far from populations with the highest risk of infection. Inexpensive methods that can be applied at the point of care (POC), especially in places with limited health infrastructure, would be a major advantage. Isothermal amplification of nucleic acids does not require thermocyclers and is relatively inexpensive and easy to implement. Among isothermal methods, recombinase polymerase amplification (RPA) is sensitive and potentially applicable at POC. We and others have developed RPA diagnostic tests to detect protozoan parasites of medical importance. Overall, our results have shown high specificity with limits of detection similar to PCR. Currently, the optimization of RPA for use at the POC is under development, and in the near future the tests should become available to detect protozoan infections in the field. In this review we discuss the current status, challenges, and future of RPA in the field of molecular diagnosis of protozoan parasites. Copyright © 2018 Elsevier B.V. All rights reserved.

Administration of kefir-fermented milk protects mice against Giardia intestinalis infection.

PubMed

Franco, Mariana Correa; Golowczyc, Marina A; De Antoni, Graciela L; Pérez, Pablo F; Humen, Martín; Serradell, María de los Angeles

2013-12-01

Giardiasis, caused by the protozoan Giardia intestinalis, is one of the most common intestinal diseases worldwide and constitutes an important problem for the public health systems of various countries. Kefir is a probiotic drink obtained by fermenting milk with 'kefir grains', which consist mainly of bacteria and yeasts that coexist in a complex symbiotic association. In this work, we studied the ability of kefir to protect mice from G. intestinalis infection, and characterized the host immune response to this probiotic in the context of the intestinal infection. Six- to 8-week-old C75BL/6 mice were separated into four groups: controls, kefir mice (receiving 1 : 100 dilution of kefir in drinking water for 14 days), Giardia mice (infected orally with 4×10(7) trophozoites of G. intestinalis at day 7) and Giardia-kefir mice (kefir-treated G. intestinalis-infected mice), and killed at 2 or 7 days post-infection. Kefir administration was able to significantly reduce the intensity of Giardia infection at 7 days post-infection. An increase in the percentage of CD4(+) T cells at 2 days post-infection was observed in the Peyer's patches (PP) of mice belonging to the Giardia group compared with the control and kefir groups, while the percentage of CD4(+) T cells in PP in the Giardia-kefir group was similar to that of controls. At 2 days post-infection, a reduction in the percentage of B220-positive major histocompatibility complex class II medium cells in PP was observed in infected mice compared with the other groups. At 7 days post-infection, Giardia-infected mice showed a reduction in RcFcε-positive cells compared with the control group, suggesting a downregulation of the inflammatory response. However, the percentages of RcFcε-positive cells did not differ from controls in the kefir and Giardia-kefir groups. An increase in IgA-positive cells was observed in the lamina propria of the kefir group compared with controls at 2 days post-infection. Interestingly, the diminished number of IgA-positive cells registered in the Giardia group at 7 days post-infection was restored by kefir feeding, although the increase in IgA-positive cells was no longer observed in the kefir group at that time. No significant differences in CXCL10 expression were registered between groups, in concordance with the absence of inflammation in small-intestinal tissue. Interestingly, a slight reduction in CCL20 expression was observed in the Giardia group, suggesting that G. intestinalis might downregulate its expression as a way of evading the inflammatory immune response. On the other hand, a trend towards an increase in TNF-α expression was observed in the kefir group, while the Giardia-kefir group showed a significant increase in TNF-α expression. Moreover, kefir-receiving mice (kefir and Giardia-kefir groups) showed an increase in the expression of IFN-γ, the most relevant Th1 cytokine, at 2 days post-infection. Our results demonstrate that feeding mice with kefir reduces G. intestinalis infection and promotes the activation of different mechanisms of humoral and cellular immunity that are downregulated by parasitic infection, thus contributing to protection.

INVESTIGATION AND EVALUATION OF CRYPTOSPORIDIUM AND GIARDIA IN COMBINED SEWER OVERFLOW (CSO) AND STORMWATER RUNOFF

EPA Science Inventory

Since the first identified Cryptosporidium outbreaks occurred in the 1980s and the massive 1993 Milwaukee, Wisconsin outbreak affected more than 400,000 people (Fox & Lytle 1996), the concern over the public health risks related to protozoan pathogens Cryptosporidium