Intestinal Protozoan Infections Research Articles

A Study of Prevalence of Intestinal Protozoan Infections and Associated Risk Factors Among the School Children of Itahari, Eastern Region of Nepal

Intestinal parasites, notably the protozoa are among the most common infections of school age children where they cause morbidity in developing countries.The objective of the study was to measure the prevalence of intestinal protozoan infec­tion and to identify risk factors associated with protozoan infection among the school children of Itahari.The cross sectional study was conducted in Grade VI, VII and VIII in schools of Itahari Municipality. Stratified random sampling method was applied to choose the schools and the study subjects. Semi-structured questionnaire was administered to the study subjects and microscopic examination of stool was done.The Chi-square test was used to measure the association of risk factors and intestinal protozoan infections.Overall intestinal protozoan infection was found to be 18.5 percent. Giardia lamblia was found high (10.5%) in comparison to Entamoeba histolytica (8%). Almost (18.4%) of male and (18.6%) of female were infected with protozoan parasites. The use of soap and water after defecation had lower prevalence of protozoan infections (16%) than only use of water (28.9%). The protozoan infection was significantly lower among having clean nail (6%) in comparison to having not clean (24.8%) respectively. We conclude that the prevalence of intestinal protozoan infection was found to be high in school children of Itahari and those having unhygienic skin, nail and clothes, and the habit of nail biting and thumb sucking was found to have significant relationship in the causation of intestinal protozoan infection. Journal of Chitwan Medical College 2013; 3(1): 32-36 DOI: http://dx.doi.org/10.3126/jcmc.v3i1.8463

Intestinal protozoan infections in the immunocompromised host

Intestinal protozoa are becoming increasingly recognized as significant pathogens in immunocompromised hosts. However, pathogenesis of infection is still poorly understood, diagnostic tests remain insensitive, and management continues to pose a challenge. Invasion by intestinal protozoa can be facilitated by impaired host T-cell immune response, although the exact pathogenesis at the cellular level is unclear. HIV-infected and transplant patients have been reported to have the highest risk for developing severe disease. Cryptosporidium is the most common parasite encountered in the immunocompromised host, followed by Cyclospora and Isospora. In recent years, Microsporidia and Blastocystis have also emerged as important players, due in part to improved molecular diagnostic assays. Effective drugs against these parasites in immunocompromised patients have not been reported in recent years. When possible, reducing the level of immunosuppression seems to be the most effective treatment strategy in combination with adjunctive antiparasitic therapy. Despite that intestinal protozoan infections cause greater morbidity and mortality in the immunocompromised host, their pathogenesis in the setting of immunosuppression is poorly understood and efforts to develop new therapeutic agents are rather limited. Improving detection and identification of species or subtypes by PCR will result in improved management decisions and a better understanding of the epidemiology of intestinal protozoa. Favorable clinical outcomes can be achieved by early detection and effective treatment of the infection. Further research on key aspects of pathogenesis at the cellular level in humans is needed.

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

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

NTDs in the Heart of Darkness: The Democratic Republic of Congo's Unknown Burden of Neglected Tropical Diseases

NTDs in the Heart of Darkness: The Democratic Republic of Congo's Unknown Burden of Neglected Tropical Diseases

Effects of hygiene and defecation behavior on helminths and intestinal protozoa infections in Taabo, Côte d'Ivoire.

BackgroundMore than 1 billion people are currently infected with soil-transmitted helminths and schistosomes. The global strategy to control helminthiases is the regular administration of anthelmintic drugs to at-risk populations. However, rapid re-infection occurs in areas where hygiene, access to clean water, and sanitation are inadequate.MethodologyIn July 2011, inhabitants from two villages and seven hamlets of the Taabo health demographic surveillance system in south-central Côte d’Ivoire provided stool and urine samples. Kato-Katz and ether-concentration methods were used for the diagnosis of Schistosoma mansoni, soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura, and hookworm), and intestinal protozoa. Urine samples were subjected to a filtration method for the diagnosis of Schistosoma haematobium. A questionnaire was administered to households to obtain information on knowledge, attitude, practice, and beliefs in relation to hygiene, sanitation, and defecation behavior. Logistic regression models were employed to assess for associations between questionnaire data and parasitic infections.Principal FindingsA total of 1,894 participants had complete data records. Parasitological examinations revealed prevalences of hookworm, S. haematobium, T. trichiura, S. mansoni, and A. lumbricoides of 33.5%, 7.0%, 1.6%, 1.3% and 0.8%, respectively. Giardia intestinalis and Entamoeba histolytica/E. dispar were detected in 15.0% and 14.4% of the participants, respectively. Only one out of five households reported the presence of a latrine, and hence, open defecation was common. Logistic regression analysis revealed that age, sex, socioeconomic status, hygiene, and defecation behavior are determinants for helminths and intestinal protozoa infections.Conclusions/SignificanceWe found that inadequate sanitation and hygiene behavior are associated with soil-transmitted helminths and intestinal protozoa infections in the Taabo area of south-central Côte d’Ivoire. Our data will serve as a benchmark to monitor the effect of community-led total sanitation and hygiene education to reduce the transmission of helminthiases and intestinal protozoa infections.

Intestinal Parasite Prevalence in an Area of Ethiopia after Implementing the SAFE Strategy, Enhanced Outreach Services, and Health Extension Program

BackgroundThe SAFE strategy aims to reduce transmission of Chlamydia trachomatis through antibiotics, improved hygiene, and sanitation. We integrated assessment of intestinal parasites into large-scale trachoma impact surveys to determine whether documented environmental improvements promoted by a trachoma program had collateral impact on intestinal parasites.MethodologyWe surveyed 99 communities for both trachoma and intestinal parasites (soil-transmitted helminths, Schistosoma mansoni, and intestinal protozoa) in South Gondar, Ethiopia. One child aged 2–15 years per household was randomly selected to provide a stool sample of which about 1 g was fixed in sodium acetate-acetic acid-formalin, concentrated with ether, and examined under a microscope by experienced laboratory technicians.Principal FindingsA total of 2,338 stool specimens were provided, processed, and linked to survey data from 2,657 randomly selected children (88% response). The zonal-level prevalence of Ascaris lumbricoides, hookworm, and Trichuris trichiura was 9.9% (95% confidence interval (CI) 7.2–12.7%), 9.7% (5.9–13.4%), and 2.6% (1.6–3.7%), respectively. The prevalence of S. mansoni was 2.9% (95% CI 0.2–5.5%) but infection was highly focal (range by community from 0–52.4%). The prevalence of any of these helminth infections was 24.2% (95% CI 17.6–30.9%) compared to 48.5% as found in a previous study in 1995 using the Kato-Katz technique. The pathogenic intestinal protozoa Giardia intestinalis and Entamoeba histolytica/E. dispar were found in 23.0% (95% CI 20.3–25.6%) and 11.1% (95% CI 8.9–13.2%) of the surveyed children, respectively. We found statistically significant increases in household latrine ownership, use of an improved water source, access to water, and face washing behavior over the past 7 years.ConclusionsImprovements in hygiene and sanitation promoted both by the SAFE strategy for trachoma and health extension program combined with preventive chemotherapy during enhanced outreach services are plausible explanations for the changing patterns of intestinal parasite prevalence. The extent of intestinal protozoa infections suggests poor water quality or unsanitary water collection and storage practices and warrants targeted intervention.

Prevalence and risk factors for intestinal protozoa infection in elderly residents at Long Term Residency Institutions in Southeastern Brazil

This study determined the prevalence of intestinal protozoa in Long Term Residency Institutions for the Elderly (ILPI) in elders, nurses and food handlers, identifying the risk factors associated with the infections. Stool samples taken from the elderly (n = 293), nurses (63) and food handlers (19) were studied. Questionnaires were used with questions related to sociodemographic variables, health, behavior and health characteristics. Stool samples were examined using the techniques of Faust and Ziehl Neelsen, and the prevalence of G. duodenalis, Cryptosporidium spp., E. histolytica/dispar in the elderly was 4.0%, 1.0% and 0.3% respectively. Nurses and food handlers showed 4.8% and 5.2% positivity only for G. duodenalis, respectively. The origin of the individuals and contact with domestic animals has been associated with infection by G. duodenalis in the elderly, and contact with domestic animals was considered a risk factor for infection. The last stool examinations were related to Cryptosporidium spp.. None of the variables were associated with E. histolytica/dispar. The frequency of hand washing was significantly associated with G. duodenalis among nurses. The frequency of positive samples of G. duodenalis, Cryptosporidium spp., E. histolytica/dispar showed that ILPIs environments are conducive to this occurring due to contact between the elderly, nurses and food handlers, which are often poorly trained in hygiene procedures and food handling.

Prevalence of intestinal protozoa infection among school-aged children on Pemba Island, Tanzania, and effect of single-dose albendazole, nitazoxanide and albendazole-nitazoxanide

BackgroundPathogenic intestinal protozoa infections are common in school-aged children in the developing world and they are frequently associated with malabsorption syndromes and gastrointestinal morbidity. Since diagnosis of these parasites is difficult, prevalence data on intestinal protozoa is scarce.MethodsWe collected two stool samples from school-aged children on Pemba Island, Tanzania, as part of a randomized controlled trial before and 3 weeks after treatment with (i) single-dose albendazole (400 mg); (ii) single-dose nitazoxanide (1,000 mg); (iii) nitazoxanide-albendazole combination (1,000 mg–400 mg), with each drug given separately on two consecutive days; and (iv) placebo. Formalin-fixed stool samples were examined for the presence of intestinal protozoa using an ether-concentration method to determine the prevalence and estimate cure rates (CRs).ResultsAlmost half (48.7%) of the children were diagnosed with at least one of the (potentially) pathogenic protozoa Giardia intestinalis, Entamoeba histolytica/E. dispar and Blastocystis hominis. Observed CRs were high for all treatment arms, including placebo. Nitazoxanide showed a significant effect compared to placebo against the non-pathogenic protozoon Entamoeba coli.ConclusionsIntestinal protozoa infections might be of substantial health relevance even in settings where they are not considered as a health problem. Examination of a single stool sample with the ether-concentration method lacks sensitivity for the diagnosis of intestinal protozoa, and hence, care is indicated when interpreting prevalence estimates and treatment effects.

Molecular and Clinical Characterization ofGiardia duodenalisInfection in Preschool Children from Lisbon, Portugal

Giardia duodenalis is the most prevalent intestinal protozoan infection especially in children. In Portugal scarce data are available relative to this infection in preschoolers. The present study was conducted from April to July 2009 in public preschools in Lisbon enrolling 316 children. Stool examination was performed through microscopy. Molecular analysis was conducted in all positive samples for G. duodenalis in order to determine the assemblage and subassemblage of this parasite. Eight of the preschoolers studied children (2.5%, 8/316) were infected with G. duodenalis. Additionally the brother of one of the infected children was also infected. Genotyping analysis targeting ssu-rRNA and β-giardin loci revealed six infections with assemblage A and 3 with assemblage B. Sub-assemblage determination was possible in four of the samples, with three A2 and one A3. The limited number of cases precluded an association of a determined symptom with an assemblage. The data presented here show the relevance of considering G. duodenalis analysis in children with intestinal complaints even in developed countries.

A Study of Prevalence of Intestinal Protozoan Infections and associated Risk Factors among the School Children of Dharan, Eastern Region of Nepal

A Study of Prevalence of Intestinal Protozoan Infections and associated Risk Factors among the School Children of Dharan, Eastern Region of Nepal

Neglected tropical diseases: operational research for elimination and control.

Neglected tropical diseases (NTDs) are the common denominator for infectious diseases that occur almost exclusively in poor populations in developing countries. The main NTDs include schistosomiasis, filariasis, intestinal helminth infections, leprosy, Buruli ulcer and protozoan infections such as trypanosomiasis (causing sleeping sickness in Africa or Chagas disease in South America) and leishmaniasis.1 While biologically diverse, they share a number of characteristics: all are strongly associated with poverty and flourish best in tropical areas, where they often coexist. Taken together, they are a leading cause of disability, comparable to tuberculosis and malaria, with over a billion people affected.1 Many predominantly target children, compromising physical growth and cognitive development. These ancient ‘companions of poverty’ undermine the wellbeing and productivity of already destitute populations, and severely impede meeting the United Nations 2015 Millennium Development Goals. By definition, NTDs have not ranked high on the national and international political agendas. For most, there are no or few adequate diagnostics, tools or vaccines, the local health systems are deficient and overburdened and financial resources scarce. In terms of research and development, these diseases are also truly neglected; less than 1% of new therapeutic developments over the past decades have concerned tropical diseases.2 The treatment of Chagas disease and African trypanosomiasis still relies on drugs that were developed more than 40–60 years ago. NTDs have fortunately received increased attention more recently from funders, global philanthropists, policy makers and researchers. A number of new global international networks have been established, and several ambitious initiatives have been launched, including some directed at the elimination of a range of NTDs.3 A major new initiative aims for the integrated control and elimination of lymphatic filiariasis, onchocerciasis, schistosomiasis, intestinal helminthiases and trachoma through the use of mass drug treatment (preventive chemotherapy) with a combination of drugs.4 However, huge knowledge gaps currently exist on how to widely implement this strategy in the most acceptable, (cost-) effective and sustainable way. Its global health impact and its interaction with and effect on already overburdened health systems remain to be better defined.5 Issues such as safety and the emergence of drug resistance also need to be carefully assessed. For other diseases, early diagnosis and treatment constitute key control measures. Although improved diagnostic tools and drugs have been developed, for example for visceral leishmaniasis, their large-scale implementation has proved challenging. While India, Nepal and Bangladesh have committed to eliminating visceral leishmaniasis by 2015, they struggle to make timely diagnosis and treatment widely accessible.6 Monitoring and surveillance systems are suboptimal. Additional operational research will need to be conducted to enhance the effectiveness of current strategies and to evaluate novel approaches. The same applies to East Africa, where treatment for visceral leishmaniasis is still predominantly provided by non-governmental organisations.6 For diseases such as African trypanosomiasis and Chagas disease, there are no easy to use, reliable tests for diagnosis and/or test of cure. Therapy is lengthy, complicated and/or often poorly tolerated. Efforts of not-for-profit research and development organisations such as the Drugs for Neglected Diseases initiative (DNDi) and the Foundation for Innovative New Diagnostics (FIND) will hopefully help fill this gap. As most NTDS are vector-borne or zoonotic in nature, efforts directed towards the control of the vector, intermediate host or animal reservoir will also be key.1 Successful control of NTDs will ultimately hinge on the concerted efforts of all stakeholders, within a multi-disciplinary approach. How to maximise the impact of these efforts will have to be carefully assessed, and innovative strategies will have to be explored. Operational research will have its role to play.7 Research findings will need to be easibly accessible, widely disseminated and able to reach decision makers and programme managers. Public Health Action is a new, open-access journal ‘disseminating new knowledge on health systems and health services for vulnerable groups’, and aiming to provide a ‘voice for operational research’. Hopefully, we can expect many operational research studies on NTDs from the field in the years to come, including in this journal.

Intestinal parasitic infections in schoolchildren in different settings of Côte d’Ivoire: effect of diagnostic approach and implications for control

BackgroundSocial-ecological systems govern parasitic infections in humans. Within the frame of assessing the accuracy of a rapid diagnostic test for Schistosoma mansoni in Côte d’Ivoire, three different endemicity settings had to be identified and schoolchildren’s intestinal parasitic infection profiles were characterized.MethodsIn September 2010, a rapid screening was conducted in 11 schools in the Azaguié district, south Côte d’Ivoire. In each school, 25 children were examined for S. mansoni and S. haematobium. Based on predefined schistosome endemicity levels, three settings were selected, where schoolchildren aged 8–12 years were asked to provide three stool and three urine samples for an in-depth appraisal of parasitic infections. Triplicate Kato-Katz thick smears were prepared from each stool sample for S. mansoni and soil-transmitted helminth diagnosis, whereas urine samples were subjected to a filtration method for S. haematobium diagnosis. Additionally, a formol-ether concentration method was used on one stool sample for the diagnosis of helminths and intestinal protozoa. Multivariable logistic regression models were employed to analyse associations between schoolchildren’s parasitic infections, age, sex and study setting.ResultsThe prevalences of S. mansoni and S. haematobium infections in the initial screening ranged from nil to 88% and from nil to 56%, respectively. The rapid screening in the three selected areas revealed prevalences of S. mansoni of 16%, 33% and 78%. Based on a more rigorous diagnostic approach, the respective prevalences increased to 33%, 53% and 92% S. haematobium prevalences were 0.8%, 4% and 65% (rapid screening results: 0.0%, 0.0% and 54%). Prevalence and intensity of Schistosoma spp., soil-transmitted helminths and intestinal protozoan infections showed setting-specific patterns. Infections with two or more species concurrently were most common in the rural setting (84%), followed by the peri-urban (28%) and urban setting (18%).ConclusionsMore sensitive diagnostic tools or rigorous sampling approaches are needed to select endemicity settings with high fidelity. The observed small-scale heterogeneity of helminths and intestinal protozoan infections has important implications for control.

NovelChlamydiaceaeDisease in Captive Salamanders

To the Editor: Although 2 major diseases of amphibians, chytridiomycosis and ranavirosis, have been relatively well studied, enigmatic amphibian disease and death not attributable to any of the known amphibian diseases frequently occur (1). We describe an apparently new disease in salamanders that is associated with a novel genus within the family Chlamydiaceae. The salamanders seen in our clinic belonged to 1 of the following species: Salamandra corsica, the Corsican fire salamander (5 animals from 1 collection); Neurergus crocatus, the yellow spotted newt (11 animals from 3 collections); or N. strauchii, Strauch’s spotted newt (6 animals from 2 collections). All salamanders were captive bred; housed in breeding colonies in private collections in Elsloo and Eindhoven, the Netherlands, Munich, Germany, and Brugge, Belgium; and 1–3 years of age. Disease was characterized by anorexia, lethargy, edema, and markedly abnormal gait. Mortality rate was 100%. Animals in these collections had no histories of disease. All animals were in good nutritional condition. Necropsy did not yield any macroscopic lesions. All animals had mild intestinal nematode or protozoan infections. Results of real-time PCRs for iridoviruses in liver and skin (2) or Batrachochytrium dendrobatidis fungus of skin (3) were negative for all animals. We placed liver suspensions from the dead salamanders on Columbia agar with 5% sheep blood and tryptic soy agar and then incubated the samples up to 14 days at 20°C. No consistent bacterial growth was observed. Histologic examination of 2 Corsican fire salamanders and 1 yellow spotted newt revealed hepatitis in 1 of the Corsican fire salamanders and the yellow spotted newt. Hepatitis was characterized by high numbers of melanomacrophages and a marked infiltration of granulocytic leukocytes. Immunohistochemical staining for chlamydia (IMAGEN Chlamydia; Oxoid, Basingstone, UK) showed cell-associated fluorescently stained aggregates in liver tissue, suggestive of Chlamydiales bacteria. Transmission electron microscopic examination of the liver of a yellow spotted newt revealed intracellular inclusions containing particles matching the morphology of reticulate or elementary bodies of Chlamydiaceae (Technical Appendix). A PCR (4) to detect the 16S rRNA of all Chlamydiales bacteria, performed on liver tissue samples from all animals, yielded positive results in all 5 Corsican fire salamanders; in 4/7, 1/3, and 1/1 yellow spotted newts; and in 4/5 and 1/1 Strauch’s spotted newts. For taxon identification, the 16S rRNA gene of the Chlamydiales bacteria was amplified and sequenced from the livers from 2 yellow spotted newts (1 from the collection in Elsloo, the Netherlands and 1 from the collection in Munich, Germany), 1 Strauch’s spotted newt, and 5 Corsican fire salamanders. The sequences shared >90% nt identity with the 16S rRNA gene of C. abortus B577 (GenBank accession no. {type:entrez-nucleotide,attrs:{text:D85709,term_id:2114161,term_text:D85709}}D85709) and therefore can be identified as a member of the family Chlamydiaceae (5). The closest 16S rRNA similarity (92%) was observed with C. psittaci strain CPX0308 ({type:entrez-nucleotide,attrs:{text:AB285329,term_id:148537245,term_text:AB285329}}AB285329). The sequence obtained from all spotted newt species specimens was identical (GenBank accession no. {type:entrez-nucleotide,attrs:{text:JN392920,term_id:358009359,term_text:JN392920}}JN392920) but differed slightly (1%) from that obtained from the fire salamander species specimens (GenBank accession no. {type:entrez-nucleotide,attrs:{text:JN392919,term_id:358009358,term_text:JN392919}}JN392919). These sequence differences point to the existence of multiple strains with possible host adaptation. We determined the phylogenetic position of the novel taxon, named Candidatus Amphibiichlamydia salamandrae (Technical Appendix), identified by using neighbor-joining analysis with Kodon software (Applied Maths, Sint-Martens-Latem, Belgium). The novel Chlamydiales forms a distinct branch in the well-supported monophyletic clade with the genera Chlamydia and Candidatus Clavochlamydia salmonicola (family Chlamydiaceae) (Figure). Maximum parsimony and unweighted pair group with arithmetic mean analyses yielded cladograms with the same topology (results not shown). Previous reports of members of the family Chlamydiaceae in amphibians concerned species occurring in other vertebrate taxa as well: C. psittaci, C. pneumoniae, C. abortus, and C. suis (6–10). To our knowledge, this member of the family Chlamydiaceae has been seen in amphibians, but not in other vertebrate hosts. The 16S rRNA analysis showed this taxon to belong to a clade with Candidatus Clavochlamydia salmonicola, a taxon found in fish. The phylogenetic position of the novel taxon in the family Chlamydiaceae thus roughly reflects the phylogenetic relation between the host species, providing evidence for host–bacterium co-evolution in the family Chlamydiaceae. Figure Topology of the novel amphibian Chlamydiaceae (Candidatus Amphibiichlamydia salamandrae) within the phylogenetic tree obtained by neighbor-joining and based on 16S rRNA gene data from representative species. Numbers show the percentage of times each branch ... Although the results obtained are not conclusive with regard to the pathogenic potential of this novel genus and species of Chlamydiales, we were not able to attribute the clinical signs to any known disease. We therefore suggest that we discovered a novel bacterial taxon with possible considerable impact on amphibian health.

Prevalence and risk factors of helminths and intestinal protozoa infections among children from primary schools in western Tajikistan

BackgroundIntestinal parasitic infections represent a public health problem in Tajikistan, but epidemiological evidence is scarce. The present study aimed at assessing the extent of helminths and intestinal protozoa infections among children of 10 schools in four districts of Tajikistan, and to make recommendations for control.MethodsA cross-sectional survey was carried out in early 2009. All children attending grades 2 and 3 (age: 7-11 years) from 10 randomly selected schools were invited to provide a stool sample and interviewed about sanitary situation and hygiene behaviour. A questionnaire pertaining to demographic and socioeconomic characteristics was addressed to the heads of households. On the spot, stool samples were subjected to duplicate Kato-Katz thick smear examination for helminth diagnosis. Additionally, 1-2 g of stool was fixed in sodium acetate-acetic acid-formalin, transferred to a specialised laboratory in Europe and examined for helminths and intestinal protozoa. The composite results from both methods served as diagnostic 'gold' standard.ResultsOut of 623 registered children, 602 participated in our survey. The overall prevalence of infection with helminths and pathogenic intestinal protozoa was 32.0% and 47.1%, respectively. There was pronounced spatial heterogeneity. The most common helminth species was Hymenolepis nana (25.8%), whereas the prevalences of Ascaris lumbricoides, hookworm and Enterobius vermicularis were below 5%. The prevalence of pathogenic intestinal protozoa, namely Giardia intestinalis and Entamoeba histolytica/E. dispar was 26.4% and 25.9%, respectively. Almost half of the households draw drinking water from unimproved sources, such as irrigation canals, rivers and unprotected wells. Sanitary facilities were pit latrines, mostly private, and a few shared with neighbours. The use of public tap/standpipe as a source of drinking water emerged as a protective factor for G. intestinalis infection. Protected spring water reduced the risk of infection with E. histolytica/E. dispar and H. nana.ConclusionsOur data obtained from the ecological 'lowland' areas in Tajikistan call for school-based deworming (recommended drugs: albendazole and metronidazole), combined with hygiene promotion and improved sanitation. Further investigations are needed to determine whether H. nana represents a public health problem.

Asymptomatic intestinal protozoan infections among inhabitants in Mexico City, Mexico

Intestinal protozoan is still an important public health problem. We aimed to gain insight into the dynamics of intestinal protozoan infection with a view to describing the prevalence of intestinal protozoan in asymptomatic individuals in Mexico City, Mexico. The study population was primarily both in and out patients from four different hospitals who were referred for routine stool examination. Faecal specimens (510) were collected over a 3-weeks period from asymptomatic individuals. Specimens were tested for a range of protozoan infection using microscopic and partly Enzyme-Linked ImmunoSorbent Assay (ELISA) method. Seven known intestinal protozoan were identified from 54 faecal specimens, a total carriage rate of 10.6%. Blastocystis hominiswere present in 22 specimens (4.31%), Entamoeba coli in 18(3.53%), Entamoeba disper in 8(1.57%), Entamoeba hartomanni in 2(0.39%), Giargia lambia in 2(0.39%),Iodoamoeba in 2(0.39%), and Endolimax nana in 1(0.2%). 10(2%) person were infected with two or more protozoa concurrently. These protozoa were all non-pathogenic, but are capable of discharging their cysts thus placing these asymptomatic carriers as potential distributors of intestinal protozoan infection. Considering the public health implication of asymptomatic carriers of intestinal protozoan infection, establishment of sustainable and regular de-worming programme in Mexico City coupled with health education messages on good hygienic practices are strongly recommend. Key words: Blastocystis hominis, Mexico, Entamoeba, protozoan fecal.

Factors associated with high prevalence of intestinal protozoan infections among patients in Sana'a City, Yemen.

BackgroundIntestinal protozoan diseases in Yemen are a significant health problem with prevalence ranging from 18% to 27%. The present study is a cross-sectional study aimed at determining the factors associated with the high prevalence of intestinal protozoan infections among patients seeking health care in Sana'a City, the capital of Yemen.Methodology/Principal FindingsStool samples were collected from 503 patients aged between 1 and 80 years old; 219 were males and 284 females. Biodata were collected via pretested standard questionnaire. Faecal samples were processed and examined for (oo)cysts or ova using a wet mount preparation after formal-ether concentration technique. Cryptosporidium oocysts were detected using the Ziehl-Neelsen staining technique. The overall prevalence of intestinal protozoan infections was 30.9%. Infection rates of Giardia duodenalis, Entamoeba histolytica/dispar and Cryptosporidium were 17.7%, 17.1% and 1%, respectively. Other parasites detected included Ascaris lumbricoides (2.4%), Schistosoma mansoni (0.3%), Hymenolepis nana (1.4%) and Enterobius vermicularis (0.4%). Multivariate analysis using forward stepwise logistic regression based on intestinal protozoan infections showed that contact with animals (OR = 1.748, 95% CI = 1.168–2.617) and taking bath less than twice a week (OR = 1.820, 95% CI = 1.192–2.779) were significant risk factors of protozoan infections.Conclusions/SignificanceThis present study indicated that intestinal protozoan infections are still a public health problem in Yemen, with Giardia and Entamoeba infections being most common. Statistical analysis indicated that low personal hygiene and contact with animals were important predictors for intestinal protozoan infections. As highlighted in this study, in order to effectively reduce these infections, a multi-sectoral effort is needed. Preventive measures should include good hygienic practices, good animal husbandry practices, heightened provision of educational health programs, health services in all governorates including rural areas. Furthermore, it is also essential to find radical solutions to the recent water crises in Yemen.

Helminth and intestinal protozoa infections, multiparasitism and risk factors in Champasack province, Lao People's Democratic Republic.

BackgroundDetailed investigations of multiparasitism are scarce in the Mekong River basin. We assessed helminth (trematode, nematode, and cestode), and intestinal protozoa infections, and multiparasitism in random population samples from three different eco-epidemiological settings in Champasack province, southern Lao People's Democratic Republic (Lao PDR), and determined underlying risk factors.MethodologyTwo stool samples were collected from 669 individuals aged ≥6 months over consecutive days and examined for helminth infections using the Kato-Katz method. Additionally, one stool sample per person was subjected to a formalin-ethyl acetate concentration technique for diagnosis of helminth and intestinal protozoa infections. Questionnaires were administered to obtain individual and household-level data pertaining to behavior, demography and socioeconomic status. Risk factors for hepato-biliary and intestinal parasitic infections and multiparasitism were determined using multiple logistic regressions analyses.Principal FindingsMultiple species intestinal parasite infections were common: 86.6% of the study participants harbored at least two and up to seven different parasites concurrently. Regarding nematode infections, hookworm was the most prevalent species (76.8%), followed by Ascaris lumbricoides (31.7%) and Trichuris trichiura (25.0%). Regarding trematodes, Opisthorchis viverrini and Schistosoma mekongi infections were found in 64.3% and 24.2% of the participants, respectively. Infections with intestinal protozoa were rare.Conclusions/SignificanceThere is a pressing need to intensify and sustain helminth control interventions in the southern part of Lao PDR. Given the high prevalence with nematode and trematode infections and the extent of multiparasitism, preventive chemotherapy is warranted. This intervention should be coupled with health education and improved access to clean water and adequate sanitation to consolidate morbidity control and enhance sustainability.

Intestinal helminth and protozoan infections in patients withchronic dermatoses

According to the statistics reports for 2005-2008, a reliable reduction in the intensive indices of lambliasis incidence rate in the Sverdlovsk region as well as tendency towards a reduction in opisthorchosis and enterobiasis incidence rate was revealed. An examination of 262 patients in the clinics of FGU UrNIIDViI revealed that the incidence of helminthic and protozoal invasions in psoriatic patients was 44.1% while the incidence of allergic dermatoses was 32.3%. Blastocysts, intestinal amoebas, seatworms as well as opisthorchid flukes in case of psoriasis dominated in terms of incidence. High prevalence of seatworms in adolescent males and women of childbearing potential was discovered.

Prevalence of intestinal parasites in patients with gastrointestinal symptoms by focus on soil-transmitted helminthes infection

Aim : The aim of this study was to determine the prevalence of soil-transmitted helminth infections (STHs) infection and other intestinal parasites in patients with gastrointestinal (GI) symptoms in Tehran Province, Iran. Background : The World Health Organization (WHO) suggests that many people in the world are chronically affected by STHs and intestinal parasites. Furthermore infection is closely correlated with poverty, poor environmental hygiene and impoverished health services. Patients and methods : In this cross-sectional study, random stool samples from 912 patients with GI symptoms were collected and examined using light microscopy and the formalin-ether concentration method for detection of protozoa and of STH eggs. Also modified acid-fast staining was used to identify Cryptosporidium parvum . Agar plate cultures were used for the recovery of Strongyloides stercoralis larvae. Results : STH infections found in these patients were Ascaris lumbricoides 5(0.5%), hookworm 3(0.3%), Hymenolepis nana 14(1.5%), Enterobius vermicularis 3(0.3%). The prevalence of protozoan parasites were 46 (5.1%), for Entamoeba coli, 31 (3.4%) for Blastosystis hominis, 27 (3%) for Giardia lamblia, 25 (2.74%) for Endolimax nana, 20 (2.2%) for Entamoeba histolytica/Entamoeba dispar complex, 12 (1.31%) for Iodomoeba butchelii 9, (1%) for Chilomastix mesenelli, and 7 (0.8%) Cryptosporidium parvum . Conclusion : A significant relationship was found between age group, location and educational achievement with STH infection but no statistical correlation was seen between demographic parameters and GI symptoms with intestinal protozoan parasites. The result of this study showed that, even in Tehran Province with a relatively high level of social hygiene, it is possible to find a high level of STH and intestinal protozoan infections.

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