Formalin-ether Method Research Articles

Molecular characterization of Strongyloides stercoralis in Mazandaran Province, North of Iran

Strongyloides stercoralis is a parasitic nematode that lives in the mucosa of the small intestine and causes strongyloidiasis in humans. Mazandaran is one of the endemic areas of this parasite in Iran. For detecting S. stercoralis larvae in stool samples various types of techniques such as PCR technique have been used. The present study was conducted to determine the molecular characteristics of S. stercoralis collected from residents of Mazandaran, northern Iran. From April to September 2017, a number of 2195 samples of human feces were collected from different regions of Mazandaran province. First, all stool samples were tested using the formalin-ether method. Then, S. stercoralis positive stool samples and 300 random samples were selected for molecular study. A set of primer pairs for conventional PCR was used in a PCR reaction to amplify the mitochondrial cytochrome c oxidase subunit 1 (Cox1) gene. To confirm the results of PCR, positive samples were sent for sequencing. The sequence was compared with reference sequences from GenBank. Phylogenetic relationships of the Cox1 gene of S. stercoralis inferred by the maximum likelihood algorithm. According to our results, in the stool test with the formal ether method, 21 stool samples (0.95%) were found to be positive for S. stercoralis and 162 samples (38.7%) were positive for other parasites . All 21 positive samples were confirmed as S. stercoralis by PCR method. The sequence of the samples overlapped 99% with S. stercoralis in the Genbank. Our results showed that conventional PCR could detect all samples that were microscopically positive.

Prevalence of Intestinal Parasites among Children Accessing Medical Healthcare at the Federal Medical Centre Keffi, Nasarawa State, Nigeria

Aim: This work was conducted between the period of April 2022 and March 2023 to investigate the prevalence and predisposing factors of enteric parasites among children accessing medical healthcare at the Federal Medical Center keffi, Nasarawa State.
 Study Design: The study was a cross-sectional study. 
 Methodology: Fresh stool specimens were collected into sterile bottles from children aged 1-15 (246 males and 194 females) who accessed medical healthcare at the Federal Medical Center keffi, Nasarawa State between the period of April 2022 and March 2023. Information such as age, gender, and drinking water sources were obtained from the subjects through a structured questionnaire. The stool specimens were observed visually for colour, consistency, and presence of blood, pus, and adult worms while the concentration of the eggs, cysts, and larvae of the intestinal parasites was carried out using the formol ether method and viewed with X10 and X40 magnifications of the binocular microscope. Data obtained from this study were analyzed using the chi-square test by the use of Statistical Package for Social Sciences (SPSS) version (21.0). Values obtained were considered significant at 95% probability.
 Results: An overall prevalence of 27.26% was obtained in the study participants with a total of five species of intestinal parasites identified. The parasites include; Entamoeba coli, Entamoeba histolytica, Giardia lamblia, Strongyloides stercoralis, and Trichomonas hominis. Entamoeba. histolytica was the most prevalent (15.45%) while S. stercoralis was the least prevalent (1.36%). In this study, males recorded a higher prevalence of Entamoeba. histolytica (16.49%) than females (14.63%) likewise for E. coli (5.14%) and (4.07%), Strongyloides stercoralis (1.55%) and (1.22%) respectively. In contrast, females recorded a higher prevalence of Giardia lamblia (2.85%) than males (2.58%) and Trichomonas hominis (3.25%) and (1.03%) respectively. The prevalence of intestinal parasites varied significantly among the age groups, with the age group 1-5 years being the most susceptible to E. histolytica (45.71%). Children who drank river water had the highest prevalence of parasitic infection (57.14%) while those who drank borehole water had the lowest majority (14.29%).
 Conclusion: The high prevalence of intestinal parasites observed in this study in relation to the sources of drinking water of the subjects suggests a major predisposing factor to intestinal parasitic infections. Therefore, the provision of potable drinking water and public enlightenment on proper hygiene practices in the study area is of great importance.

Prevalence of Gastrointestinal Parasites in Slum Children of Dhaka City: Comparison of Two Coprological Methods

The present study aimed to measure the prevalence of intestinal parasites among children with gastrointestinal tract infections from different slum areas of Dhaka. Furthermore, a comparison was made of the accuracy of direct smear (DS) and formol-ether concentration (FEC) techniques in the detection of infection. The overall prevalence of parasitic infection was 72.46% with a combined method. By direct smear, 2 species of protozoa (11.59%), 2 species of cestode (5.07%) and 4 species of nematode (18.12%) parasites were detected whereas by formol – ether concentration method, 5 species of protozoa (28.26%), 1 species of Trematode (1.44%), 2 species of cestode (17.39%) and 5 species of nematode (79.71%) parasites were detected. By direct smear (DS) and formol-ether concentration (FEC) the prevalence of intestinal parasites was 42% and 58% respectively. Ascaris lumbricoides was the most common parasite detected by both formol-ether concentration (37.68%) and direct smear method (7.97%). A statistically significant association (P < 0.001) was found between the test methods, age groups and months with parasitic infection. Direct smear showed less sensitivity than formol-ether concentration technique (100%). The diagnostic performance of formol-ether technique for the diagnosis of intestinal parasites in slum children was remarkably higher as related to direct smear in the present study. Therefore, the DS and FEC combined techniques should be used as routine investigative techniques for the identification of intestinal parasites. Henceforth, it is advantageous to use the formol-ether method to complement the direct smear method. Bangladesh J. Zool. 50(3): 353-361, 2022

Toxocara Infection in Dogs and Cats in Isfahan Province of Iran in 2021.

Toxocariasis is an acute or chronic disease caused by parasites of the Ascaridae family, especially Toxocara of dogs and cats. Eggs are excreted out by feces of these animals on soil. Infective eggs develop on soil which can be infective to human. In this study, infection rate of Toxocara spp. in dogs and cats of urban and rural areas of Isfahan province of Iran has been investigated. Three hundred and seventy-five stray dog feces and 230 stray cat feces were collected from the public environment (slaughterhouses, parks, children's playgrounds, student dormitories, university environment, streets and squares) in Isfahan province of Iran. At first, dogs' and cats' feces were examined for the presence of Toxocara spp. eggs using formalin ether method. In the second stage, by using molecular methods, Toxocara eggs spp. (Toxocara canis or Toxocara cati) were identified. From 375 dog fecal samples, 39 (10.40%) and from 230 cat fecal samples, 38 (16.52%) were positive for presence of the Toxocara eggs. Dogs and cats in Isfahan province of Iran were infected with Toxocara parasite. These infections can be potential risk for human toxocariasis.

INTESTINAL PARASITE INFECTIONS AND ASSOCIATED RISK FACTORS IN INHABITANTS OF THE CITY OF YAOUNDÉ, CAMEROON

Intestinal parasite infections are still prevalent in developing countries and in Cameroon where over 90% of the population is at high risk. To assess the distribution of intestinal parasitic infections and risk factors of the city of Yaoundé, both household and parasitological surveys were conducted from October to December 2019 among inhabitants of lowlands aged from 15 years and over. Stools samples were collected and screened for intestinal parasites presence using Kato Katz and Formol-Ether methods. Sociodemographic status, prevention measures against intestinal parasitic diseases and practices with increase exposition to risky environments were then recorded.
 A total of 229 participants (142 females: 62.0%; 87 males: 38.0%) were enrolled for the study, and 24.02% (55/229) were found infected by helminthes (ten species) and/or protozoans (one species). Participant infection rates and risk varied by parasite species and socio-demographic factors. Global risk analysis showed that age (OR ranges: 3.78-15.96), anti-parasitic drug consumption (OR: 2.53), eating behavior,,hygiene (OR: 22.4), occupation (OR ranges: 1.92-3.53) and type of toilets (OR: 3.4) were strongly associated with risk of infection by intestinal parasites. The risk increased in 15-30 years age group for A. lumbricoïdes, T. trichiura and Schistosoma mansoni, unpredictably in those washing their hands before meals for A. lumbricoïdes and H. nana, in respondents using antiparasitic drugs as auto-medication for H. nana and in those using traditional toilets for A. lumbricoïdes. However, other variables with high OR values (> 5.0) might be potential risk factor for the occurrence of specific parasite infections. The study suggests the need for household sensitization and community actions including integrated environmental management as complement strategy to reduce intestinal parasite transmission in the city of Yaoundé.

Gastrointestinal parasites of six large mammals in the Wasgomuwa National Park, Sri Lanka.

Gastrointestinal (GI) parasites may impose detrimental consequences on wildlife populations due to their capacity to cause mortality and reduce fitness. Additionally, wild animals play an important role in the transmission of zoonoses. Despite this importance, information on GI parasites of tropical wild mammals is critically lacking. The present study aimed to document GI parasites of six wild-dwelling large mammal taxa in Sri Lanka: Asian elephant (Elephas maximus), Sloth bear (Melursus ursinus), civet (Paradoxurus sp.), Leopard (Panthera pardus), Grey langur (Semnopithecus priam) and buffalo (Bubalus sp). Fresh faecal samples (n = 56) collected from the Wasgomuwa National Park, Sri Lanka were subjected to coprological examination using faecal smears, and the brine floatation technique followed by microscopic identification; quantitative data were accrued using the formol-ether method. The survey revealed a high prevalence of GI parasites, where 86% (48/56) of faecal samples screened positive for parasitic infections. Faecal samples of the civet, buffalo and Leopard recorded 100% prevalence, while the lowest (40%) was recorded for the Grey langur. Eight types of GI parasites were documented: protozoan cysts, platyhelminth ova (three types of digenean and a single cyclophillidean type), nematode ova (strongyle, strongyloid, ascarid, and trichuroid types) and rhabditiform larvae. The buffaloes and civets had a comparatively high number and diversity of GI parasites (buffalo: 7 types, H’ = 1.02; civet: 6 types, H’ = 1.52), whilst only a single type (digenean) was detected in the Grey langur. Likewise, parasite loads were also highly variable; highest in the bear (486 per g faeces) and lowest in the monkey (10 per g faeces). The outcome of this survey is important on two accounts; i) to fill the knowledge gap on GI parasites of tropical wild mammals, and ii) the revelation of many first-time parasite-host records for some of the threatened wild-dwelling large mammals in Sri Lanka.

Prevalence of Cryptosporidium in Children Under 13 Years of Age With Acute Diarrhea in Tabriz, Iran

Introduction: Cryptosporidium is a coccidian parasite that causes diarrhea in animals and humans, especially children. Although several studies have been done on Cryptosporidium infection in some parts of Iran, this parasite is not examined in routine parasitological tests. Therefore, the aim of this study was to determine the frequency of Cryptosporidium infection in children with diarrhea in Tabriz, Iran. Materials and Methods: In this study, 100 fecal samples of children under 13 years of age with acute diarrhea who referred to medical diagnostic laboratories in Tabriz during 2018 were examined for Cryptosporidium infection. The samples were first concentrated by formalin-ether method and after staining with modified acid fast method, they were examined by light microscope. Results: In this study, 3 children (3%), 2 boys, 3 years old and 5 years old, and a 3-year-old girl had cryptosporidiosis. Conclusion: The results of the present study show the presence of Cryptosporidium infection in children in Tabriz. The very low percentage of infection with this parasite indicates that this parasite is not yet considered as a health problem in this area.

Preliminary Survey of the Intestinal Helminths of Grasscutter and Antelope (Bush Meat) in Omagwa Rivers State

The preliminary investigation on the prevalence of intestinal helminths in two popularly consumed wild games (bushmeat) Thryonomys swinderianus (grasscutter) and Alcelaphinaespp. (antelope) from Omagwa district in River State, Nigeria was carried out using the concentration technique (formalin ether method) and fecal egg count/larvae count technique. A total of 110 slaughtered animals were used, 45 males (40.9%) and 65 females (59.1%), of this total number of the test samples, 60 (54.5%) were grasscutters consisting of 25 (41.7%) males and 35 (58.3%) females and antelopes were 50 (45.5%) consisting of 20 (40.0%) males and 30 (60.0%) females. In general, out of the total number of grasscutters examined, 15 (37.5%) males and 25 (62.5%) females were infected with the intestinal helminths. Also, from the total number of antelopes examined, 10 (38.5%) males and 16 (61.5%) females were infected. And the result from t-Test showed that there were no significant difference (P > 0.05) from the number of samples examined, as both test samples were infected by different intestinal helminths, irrespective of the highest rate of infection shown by the females at 41 (62.1%) as against males at 25 (37.9%). In addition, this result revealed the presence of seven different species of intestinal helminths (Ascarisspp,Strongyloidesspp, Trichurisspp, Fasciolaspp, Taeniaspp, Moniliformisspp, and Hookworm) of which Ascaris spp., Strongyloides spp., Taenia spp., and Hookworm were present in both and Trichuris spp., withMoniliformis spp. being presentin grasscutters, while Fasciola spp. was only foundin antelope. The females from both test samples has the highest count of ova/worm of the intestinal helminthic as at 162 (antelopes) and 81 (grasscutters) against the males at 79 (antelopes) and 40 (grasscutters). But the result from ANOVA shows that there were no statistical significant difference (P > 0.05) in the prevalence of intestinal helminthic ova’s/worm’s between the male and female of both test sample. It is believed that this study will spark further research into the other types of consumable bushmeats and at the same time draw the attention of necessary bodies into the monitoring of the activities of various eateries and outlets where these meats are served, so as to ensure that good hygiene is maintained.

Intestinal protozoan and helminthic infections among hemodialysis and cancer patients.

Intestinal parasitic infections (IPIs) can be a severe threat to immunocompromised patients. This is particularly true for those undergoing chemotherapy and hemodialysis. The present research is aimed at identifying intestinal parasites that might be present in immunocompromised patients. In this cross-sectional study 1040 stool samples were collected from March to September 2017. Six hundred and forty-one stool samples from immunocompromised patients (279 samples from hemodialysis patients and 362 samples from chemotherapy patients) and 399 samples from the control group were collected in Guilan province, Iran. The samples were tested by direct, formalin-ether methods for protozoa and ova of intestinal parasites and Ziehl-Neelsen staining methods for coccidian parasites such as Cryptosporidium species. The overall parasitic infection rate was highest (15%) in hemodialysis patients and 11.3% in chemotherapy patients, whereas the lowest rate was observed (7.3%) in the control group. The infectivity rates were statistically significant (P = 0.008) when compared with the control group. The parasites found were Blastocystis hominis (8.9% of the cases), Entamoeba coli (1.6%), Iodamoeba butschlii (0.8%), Endolimax nana (0.6%), Chilomastix mesnili (0.5%), Strongyloides stercoralis (0.5%), and Taenia species (0.15%), whereas Giardia lamblia was detected only in the control group. There was not a correlation between prevalence of parasites with age or education levels of the infected individuals. Results of the present study suggest that periodic stool examinations in special parasitological laboratories should be included as part of routine and general medical care.

Molecular identification of Echinococcus granulosus sensu lato by mitochondrial COX1 and SSU-rDNA markers in dogs in the west of Iran

Echinococcus granulosus sensu lato (E. granulosus s. l.) is important in terms of the medical and veterinary sciences, especially in the tropical and subtropical regions. Stray and domestic dogs are the most important definitive hosts for this parasite. The aim of this study was to determine the prevalence of E. granulosus s. l. among stray and domestic dogs using copro-nested PCR method in the west of Iran. Accordingly, 605 faecal samples of domestic (n = 424) and stray (n = 181) dogs were collected from Kermanshah (n = 301) and Lorestan (n = 304) Provinces, in the west of Iran. Initially, the samples were concentrated using formalin-ether method and the precipitates were collected for further examination using copro-PCR method using COX1 and SSU-rDNA markers in order to detect taeniid parasites and E. granulosus s. l., respectively. Totally, taeniid parasites were observed in 38 (6.28%) samples, of which 21 (3.47%) samples in domestic dogs and 17 (2.8%) samples in stray dogs were detected. Moreover, of 38 taeniid positive samples, 21 (3.47%) samples were positive for E. granulosus s. l that 13 (2.14%) samples in domestic dogs and 8 (1.32%) samples in stray dogs were detected. In conclusion, the findings of the current study specified that the overall prevalence of echinococcosis was low (3.47%) in domestic and stray dogs in the examined areas. Since western Iran is one of the areas with high potential for transmission of E. granulosus s. l., regular monitoring of the prevalence of this disease in both the final hosts and the intermediate hosts is important at regular intervals.

Prevalence and associated risk factors of intestinal helminthic infections in children from Lorestan province, Western Iran

BackgroundIntestinal helminthic infections are among the most important global socioeconomic and health problems. This study aimed to estimate the frequency of intestinal parasites in 366 children aged 2 to 15 years referred to the main pediatric health center of Lorestan Province, Iran. MethodsMicroscopic analysis was performed on 366 stool samples. We applied direct smear, scotch tape, and formol-ether methods. Moreover, a questionnaire was filled in by parents or guardians of the children. ResultsThe results showed that 36 children (9.8%) were infected with at least one or more intestinal parasites. The most prevalent parasites were Enterobius vermicularis (6.8%), Hymenolepis nana (1.9%), and Ascaris lumbricoides (0.55%), in the order of their appearance. Statistical analysis showed that several risk factors were significantly associated with the prevalence intestinal helminthic parasites, including male sex (OR = 2.9; 95% CI: 1.2–6.2; p < 0.05), residing in rural regions (OR = 4.2; 95% CI: 2.1–10.6; p < 0.001), no handwashing habit before eating (OR = 5.2; 95% CI: 2.2–12.5; p < 0.001), and consuming raw or unwashed vegetables and fruits (OR = 4.8; 95% CI: 2.3–11.2; p < 0.001). ConclusionThe present study showed a high overall frequency of intestinal helminthic infections among the children in Lorestan province, Iran. The results of the risk factor analysis suggest that improving environmental hygiene and health education would be important for effective control of intestinal parasitic infections.

Initial Evidences of Salt and Pepper Retinal Lesions (SPRL) in Patients with Intestinal Protozoan Infections in Iran.

It is made clear that salt and pepper retinal lesion (SPRL) has subsequently associated with the infection with Giardia lamblia (G. lamblia). However, little is known regarding the prevalence of SPRL among patients suffered from parasitic infections in the world. This study aimed to determine the prevalence of SPRL among patients with intestinal protozoan infections, for the first time, in Sari, northern Iran. In this case-control study, a total of 150 subjects participated: 75 were in the patients group diagnosed to have an intestinal parasite and 75 in the control group without any intestinal infection. Fecal samples were obtained from all participants and examined with wet mount and formalin-ether methods. The retina of both groups was examined by an ophthalmologist. Overall, salt and pepper retinal changes were diagnosed in 12 (16 %) patients with at least one parasitic infection (7 females and 5 males). G. lamblia was diagnosed in 6 subjects (50%), Blastocystis hominis in 5 (41.6%), and Entamoeba coli in 1 (8.3 %). Most of the patients (58.3%) had a mild infection. Bilateral retinal involvement was observed in 75% of the patients. Furthermore, macula involvement was observed in 91.7 % with SPRL. Our findings indicated the relatively high prevalence of SPRL in subjects with giardiasis and blastocystosis. It can be concluded that not only G. lamblia but also B. hominis can cause SPRL in Sari, Iran. Further studies are needed to find other etiologic parasites able to cause retinal damages.

Soil-Transmitted Protozoans and Helminths from Market Gardening Sites of Yaounde, Cameroon

Background: In Cameroon, the practice of market gardening exposes both the farmers and consumers to a certain number of health-related hazards. Environmental health risks associated to this activity showed that it was responsible for the increased of transmission risk of the human and animal intestinal worms. Methods: The epidemiology of soil borne diseases associated with urban agriculture was furthermore considered in three market garden sites of the city of Yaounde (Tsinga, Nkolondom, Nkolbisson). From October to December 2016, water and soils from rivers, wells and furrows were analysed for physicochemical characteristics and parasite identification using Kato-Katz and Formol-Ether methods. Results: Means of water parameters and parasite composition varied per locations and environments in the 82 samples analyzed. Ranges of mean temperature, pH, electrical conductivity, turbidity and color of water samples were 25.2-25.5°C (), 6.53-7.01 UC, 308-502 µS.cm-1, 637-1,300 FTU and 2,451-6,422 Co-Pt, respectively. Soil parasites consisted of 3 protozoans (Entamoeba histolytica, Sarcocystis sp. and Giardia intestinalis) and 11 helminths (Fasciola hepatica, Diphyllibotrium latum, Ascaris lumbricoides, Trichuirus trichiura, Ancylostoma sp., Trichostrongylus sp., Schistosoma mansoni, Schistosoma sp., Paragonimus westermanii, Strongyloides stercoralis and Hymenolepis nana). Conclusion: The presence of viable helminths suggests that harmful soil pathogens such as protozoans and helminths can spread through market gardening. This reminds on the need to find better ways to alleviate the control of intestinal parasitic infections which, nevertheless, are classified as neglected tropical diseases.

Diagnostic Performance of Mini Parasep® Solvent-Free Foecal Parasite Concentrator for the Diagnosis of Intestinal Parasitic Infections

AbstractIntroduction: Various stool concentration techniques have been used to increase the microscopic detection of parasites. We assessed the enclosed, single-vial, Mini Parasep® technique in comparison to the currently used coprodiagnosis procedures. Materials and Methods: A total of 150 stool samples were collected. Samples concentrated by formol–ether method (FEM) and Mini Parasep® SF foecal concentrator and unconcentrated samples were subjected to wet mount, iodine mount microscopy and smear examination by modified acid-fast staining. Results: Direct wet mount detected 72 positive samples (48.6%), whereas 77 (51.3%) and 80 (53.3%) samples were detected by FEM and Mini Parasep® SF methods, respectively. The sensitivity of detection of parasites was 98.7%, 95% and 90.1% with Mini Parasep®, FEM and direct microscopy, respectively. A clearer background with less foecal debris and a better yield of Hymenolepis nana, Trichuris trichiura, Entamoeba coli and Giardia lamblia were noted with Mini Parasep®. Conclusion: Mini Parasep® SF technique is simple, rapid and less cumbersome than conventional diagnostics, making it suitable for routine use. In addition, it offers higher sensitivity and better background clearance than both direct stool examination and FEM.

The Prevalence of Intestinal Parasites and Associated risk Factors among Students of Jahrom University of Medical Sciences

Background: Parasitic infections, especially intestinal agents could affect social and personal hygiene and health; and to avoid the spread of pollution, monitoring the infectious sources is critical. Objective: The aim of this study is to estimate the prevalence of intestinal parasites and identify factors associated with intestinal parasitic infections among students of Jahrom University of Medical Sciences between 2013-1014. Materials and Methods: This study was carried out between September 2013and February 2014. A total number of 1293 stool samples were taken from 431 students and were examined by direct wet mounting and formalin-ether methods. A questionnaire for common risk factors was completed for each individual. Results: Overall, the prevalence of intestinal parasitic infections was estimated to be 125 (29%) that infected by pathogenic and non-pathogenic intestinal parasites. Various species of protozoan infections were detected: Entamoeba coli was the most common parasite (9.04%) followed by Blastocystis hominis (8.12%), and Giardia lamblia (4.64%). About 3.2% students were infected with multiple parasites. A significant association was observed between the prevalence of intestinal parasite infections with the type of accommodation (OR=1. 5; 95% CI: 1.1; 1.9), parents’ educational level (OR=1. 5; 95% CI: 1.1; 1.9) and gender (OR=1. 5; 95% CI: 1.1; 1.9). No age association was detected, and a slightly positive prevalence with increasing age was observed (p=0.66). Conclusions: These data showed intestinal parasites were slightly more prevalent than expected, that might be due to interior sources of infection in college, such as carrier students. Hence, performing periodic monitoring among students is a necessity to promote the hygiene of the students.

Malaria and intestinal parasitosis in pregnant woman at Abobo district (Abidjan, Côte d'Ivoire)

A prospective study was carried out from 2010 to 2012 at the Hôpital Général d'Abobo (HGA) in Abidjan, in order to determine the impact of infectious and parasitic diseases on child cognitive development. Blood samples were examined by means of thick drop and blood smear; as for stool by direct examination and concentration by formalin-ether method. We evaluated the prevalence, the parasite load of malaria and gastrointestinal parasites; then we investigated the risk factors for these disorders. Overall, 331 pregnant women in the last trimester of their pregnancy were enrolled. The plasmodic index was 3.9% with infestation specific rates of P. falciparum from 100%. Concerning digestive protozoa, it has been observed 71.3% of nonpathogenic, against 9.7 % of pathogens, either an overall prevalence of 51.4% of digestive parasites. The calculated average parasitic loads revealed 3089.2 tpz/μl of blood (95 % CI: 591.1-5587.3) for malaria, 6.5 eggs per gram of stool (95 % CI: 0.4-13.4) for intestinal helminths and one parasite by microscopic field for protozoa (common infestation). It has been shown that the occurrence of malaria has been linked to the non-use of impregnated mosquito nets (x2 = 0.012; p = 0.018), not to age. No link could be established between the presence of digestive parasites and the age of pregnant women, or socioeconomic conditions (level of education, profession, type of toilet). Malaria is less common in pregnant women while the rate of digestive parasites remains high.

Evaluation of a Real-Time Polymerase Chain Reaction for the Laboratory Diagnosis of Giardia intestinalis in Stool Samples from Schoolchildren from the Centre-Ouest and Plateau Central Regions of Burkina Faso

Objective: Giardiasis, a zoonotic, diarrheal disease with worldwide occurrence, is routinely diagnosed by microscopic examination of stool samples. However, implementation of this method relies on skilled and experienced personal; it is time consuming and relatively low in sensitivity. A superior diagnostic approach to detect the causative agent Giardia intestinalis would, hence, be highly desirable. The current study aimed to assess realtime polymerase chain reaction (PCR) for the detection of G. intestinalis as an alternative to microscopy. Material and methods: Stool samples from healthy schoolchildren aged 8-14 years from eight schools of the Centre-Ouest and Plateau Central regions in Burkina Faso were therefore collected within a cross-sectional study. Microscopic examination was performed on two faecal samples collected over two consecutive days from 441 schoolchildren. Each faecal specimen has been examined using Kato-Katz and formol-ether methods of concentration in addition to the direct examination. Real-time PCR was used to detect G. intestinalis in the 94 microscopy positive and the 53 microscopy negative samples. Results: Microscopic examination demonstrated an overall G.intestinalis prevalence of 27.2%. Using the microscopic examination as the ‘gold standard’, the overall sensitivity of real-time PCR was demonstrated to be 76.6% ranging from 58.3% to 94.1% and the specificity was 96.2% ranging from 96.2% to 100% across the schools assessed. Conclusion: Real-time PCR appears to be a solid detection method for G. intestinalis in this current setting. However, it needs to be further optimized to become a more sensitive tool for G. intestinalis diagnosis in low income settings.

Soil-transmitted Helminth Infections in Schoolchildren of Laguna de Perlas (Nicaragua).

Soil-transmitted helminth (STH) prevalence, intensity, polyparasitism and co-infections in 425 children from 3 schools of Laguna de Perlas (Nicaragua) were investigated. Single stool samples were analysed by the formalin-ether method and the Kato-Katz. A total of 402 (94.6%) children were infected. Trichuris trichiura 308 (72.4%), Ascaris lumbricoides 115 (27.1%) and Hookworms 54 (12.7%) were the most prevalent STHs. Polyparasitism (322; 75.8%) with two species was most prevalent (109; 25.6%). T. trichiura with A. lumbricoides (19.3%) and T. trichiura with Hookworm (6.8%) were the most common combinations. Positive associations were observed between T. trichiura and A. lumbricoides and T. trichiura and Hookworm (p = 0.0001). Highest Hookworm intensities appeared when three STH co-infections occurred. Moderate- heavy STH intensities appear in up to 42.1% in trichuriasis, 57.5% in ascariasis and 11.1% in Hookworm infections. Integrated control interventions covering children need to be implemented mainly in a rural environment.

Intestinal parasites of children and adults in a remote Aboriginal community of the Northern Territory, Australia, 1994-1996.

Parasitic infections can adversely impact health, nutritional status and educational attainment. This study investigated hookworm and other intestinal parasites in an Aboriginal community in Australia from 1994 to 1996. Seven surveys for intestinal parasites were conducted by a quantitative formol-ether method on faecal samples. Serological testing was conducted for Strongyloides stercoralis and Toxocara canis IgG by enzyme-linked immunosorbent assays. Of the 314 participants, infections were as follows: Trichuris trichiura (86%); hookworm, predominantly Ancylostoma duodenale (36%); Entamoeba spp. (E. histolytica complex [E. histolytica, E. dispar and E. moskovski], E. coli and E. hartmanni) (25%); S. stercoralis (19%); Rodentolepis nana (16%); and Giardia duodenalis (10%). Serological diagnosis for 29 individuals showed that 28% were positive for S. stercoralis and 21% for T. canis. There was a decrease in the proportion positive for hookworm over the two-year period but not for the other parasite species. The presence of hookworm, T. trichiura and Entamoeba spp. was significantly greater in 5-14 year olds (n = 87) than in 0-4 year olds (n = 41), while the presence of S. stercoralis, R. nana, G. duodenalis and Entamoeba spp. in 5-14 year olds was significantly greater than 15-69 year olds (n = 91). Faecal testing indicated a very high prevalence of intestinal parasites, especially in schoolchildren. The decrease in percentage positive for hookworm over the two years was likely due to the albendazole deworming programme, and recent evidence indicates that the prevalence of hookworm is now low. However there was no sustained decrease in percentage positive for the other parasite species.

Neglected tropical diseases: prevalence and risk factors for schistosomiasis and soil-transmitted helminthiasis in a region of Minas Gerais State, Brazil

Among the neglected tropical diseases (NTDs), schistosomiasis and the three main soil-transmitted helminthiases (STHs), i.e., ascariasis, trichuriasis and hookworm infection, represent the most common infections in developing countries. In Brazil, there is a lack of epidemiological data in many parts of the country, which favors the unawareness of the real situation concerning these diseases. Due to this, we investigated the occurrence of schistosomiasis and STHs in a region of Minas Gerais State, Brazil. One stool sample was collected from 503 individuals, whose ages ranged from 0.1 to 91.2 years, and screened using both the Kato-Katz and the Formol-Ether methods. In parallel, a malacological survey was carried out in the main water bodies of the district, and Biomphalaria susceptibility assays and kernel-based techniques were also performed. No individual was found infected with Ascaris lumbricoides or hookworm. Schistosoma mansoni was the most common parasite found (1.6%). The prevalence was higher in males and the chance of acquiring the disease increased by 43.35 times with contact with a body of water. None of the Biomphalaria tenagophila and B. glabrata specimens were found naturally infected, but B. glabrata was highly susceptible to infection with Schistosoma mansoni. Using kernel-based techniques, clusters of Biomphalaria were found near the households where the infected individuals lived. Schistosomiasis was the most prevalent parasitic infection found. Our findings show that the occurrence of this disease has been underestimated by the local health care service, and highlight the importance of epidemiological surveillance in areas of low prevalence for schistosomiasis.