Ascaris Eggs Research Articles

Molecular identification of Ascaris lumbricoides and Ascaris suum recovered from humans and pigs in Thailand, Lao PDR, and Myanmar.

Ascaris lumbricoides is the largest roundworm known from the human intestine while Ascaris suum is an internal parasite of pigs. Ascariasis, caused by Ascaris lumbricoides, has a worldwide distribution. Here, we have provided the first molecular identification of Ascaris eggs and adults recovered from humans and pigs in Thailand, Lao PDR, and Myanmar. We amplified and sequenced nuclear ribosomal DNA (ITS1 and ITS2 regions) and mitochondrial DNA (cox1 gene). Sequence chromatograms of PCR-amplified ITS1 region revealed a probable hybrid genotype from two human ascariasis cases from Chiang Mai Province, northern Thailand. All complete ITS2 sequences were identical and did not differ between the species. Phylogenetic trees and haplotype analysis of cox1 sequences showed three clusters with 99 haplotypes. Forty-seven samples from the present study represented 14 haplotypes, including 7 new haplotypes. To our knowledge, this is the first molecular confirmation of Ascaris species in Thailand, Lao PDR, and Myanmar. Zoonotic cross-transmission of Ascaris roundworm between pigs and humans probably occurs in these countries.

Effect of the nematophagous fungus Pochonia chlamydosporia on soil content of ascarid eggs and infection levels in exposed hens

BackgroundThe nematophagous fungus Pochonia chlamydosporia can degrade ascarid (e.g. Ascaridia galli) eggs in agar and soil in vitro. However, it has not been investigated how this translates to reduced infection levels in naturally exposed chickens. We thus tested the infectivity of soil artificially contaminated with A. galli (and a few Heterakis gallinarum) eggs and treated with P. chlamydosporia. Sterilised and non-sterilised soils were used to examine any influence of natural soil biota.MethodsUnembryonated eggs were mixed with sterilised (S)/non-sterilised (N) soil, either treated with the fungus (F) or left as untreated controls (C) and incubated (22 °C, 35 days) to allow eggs to embryonate and fungus to grow. Egg number in soil was estimated on days 0 and 35 post-incubation. Hens were exposed to the soil (SC/SF/NC/NF) four times over 12 days by mixing soil into the feed. On day 42 post-first-exposure (p.f.e.), the hens were euthanized and parasites were recovered. Serum A. galli IgY level and ascarid eggs per gram of faeces (EPG) were examined on days -1 and 36 (IgY) or 40 p.f.e. (EPG).ResultsEgg recovery in SF soil was substantially lower than in SC soil, but recovery was not significantly different between NF and NC soils. SF hens had a mean worm count of 76 whereas the other groups had means of 355–453. Early mature/mature A. galli were recovered from SF hens whereas hens in the other groups harboured mainly immature A. galli. Heterakis gallinarum counts were low overall, especially in SF. The SF post-exposure IgY response was significantly lower while EPG was significantly higher compared to the other groups.ConclusionsPochonia chlamydosporia was very effective in reducing ascarid egg numbers in sterilised soil and thus worm burdens in the exposed hens. However, reduced exposure of hens shifted A. galli populations toward a higher proportion of mature worms and resulted in a higher faecal egg excretion within the study period. This highlights a fundamental problem in ascarid control: if not all eggs in the farm environment are inactivated, the resulting low level infections may result in higher contamination levels with associated negative long-term consequences.

‘LaDePa’ process for the drying and pasteurization of faecal sludge from VIP latrines using infrared radiation

This paper studies a faecal sludge treatment process, LaDePa (Latrine Dehydration and Pasteurization), which includes: (i) the characterization of the rheological and plastic behaviour of faecal sludge in the feeding section; (ii) the study of the drying and pasteurization performance of the process using a laboratory-scale prototype; and (iii) an evaluation of the processed faecal sludge for reuse in agriculture or as a biofuel.Experiments conducted using a rheometer show that the faecal sludge exhibits shear thinning behaviour, i.e. viscosity decrease with shear rate increase. Plasticity tests in a cone penetrometer showed that the faecal sludge has a more liquid than plastic behaviour, which may affect extrusion quality, unless a plasticizer is added, as sawdust in this study.The extent of drying and pasteurization of the samples was determined based on moisture content and the presence of viable Ascaris eggs respectively. As the intensity of infrared radiation was increased, drying was faster and more efficient in terms of energy consumption. However, the pellets were thermally degraded at temperatures above 200 °C. After processing in the LaDePa, Ascaris eggs were deactivated or severely damaged so that they would be not able to develop.The last part of the study was conducted by determining the content of nutrients (C, N, P, K) and calorific value. The results showed that the processed pellets have suitable characteristics for reuse in agriculture and as a biofuel: similar nutrient content to manure and compost, and similar calorific value to wood. Drying did not affect the nutrient content and calorific value of the dry bone of faecal sludge.

Biological control of house fly

We determined that Musca domestica L. is the most abundant zoophilous fly in the pig stock complex. Musca domestica has been found to play a leading role in the transfer of exogenous forms of helminths. We also identified the Ascaris and Oesophagostomum eggs in our study. We proved that the Musca stabulans could be the source of environmental pollution of eggs by Trichostrongylidae. Our data concerning the laboratory breeding Hydrotea aenescens testified the possibility of its use as a biological agent that could control the harmful activity of houses fly at livestock farms and complexes. We revealed that one generation of Hydrotea aenescens could grow in 24 days at optimum temperatures of 26-27 °C. Lowering the temperature to 20 °C had prolonged the generation time to 40 days and reduced the age of the imago from 20 to 14 days. Low positive temperatures delayed the development of larvae, but not affected the basic biological characteristics of the species. We also established that the density of 0.5-1.0 larvae/cm 3 per substrate was optimal; when we increased the density, this lead to a decreasing the viability of the species. The consumption of house fly larvae by predator larvae grows with an increase in the prey density. Thus, we registered that the larva can destroy 11 larvae of house fly per day.

Removal of helminth eggs by centralized and decentralized wastewater treatment plants in South Africa and Lesotho: health implications for direct and indirect exposure to the effluents

Wastewater may contain contaminants harmful to human health; hence, there is the need for treatment before discharge. Centralized wastewater treatment systems are the favored treatment options globally, but these are not necessarily superior in reduction of pathogens as compared to decentralized wastewater treatment systems (collectively called DEWATS). This study was therefore undertaken to assess the soil-transmitted helminth (STH) and Taenia sp. egg reduction efficiency of selected anaerobic baffled reactors and planted gravel filters compared to centralized wastewater treatment plants in South Africa and Lesotho. The risk of ascariasis with exposure to effluents from the centralized wastewater treatment plants was also assessed using the quantitative microbial risk assessment (QMRA) approach. Eggs of Ascaris spp., hookworm, Trichuris spp., Taenia spp., and Toxocara spp. were commonly detected in the untreated wastewater. The DEWATS plants removed between 95 and 100% of the STH and Taenia sp. eggs, with centralized plants removing between 67 and 100%. Helminth egg concentrations in the final effluents from the centralized wastewater treatment plants were consistently higher than those in the WHO recommended guideline (≤ 1 helminth egg/L) for agricultural use resulting in higher risk of ascariasis. Therefore, in conclusion, DEWATS plants may be more efficient in reducing the concentration of helminth eggs in wastewater, resulting in lower risks of STH infections upon exposure.

The sanitation of farm animal manure from parasites

Οι κοπροσωροί που συγκeντρώνονται στις κτηνοτροφικές και πτηνοτροφικές eκμeταλλeύσeις μπορeί να αποτeλέσουν eστίeς μeτάδοσης παρασιτικών νοσημάτων και αιτία για την υποβάθμιση του πeριβάλλοντος. Στην παρούσα eργασία παρουσιάζονται οι διάφορeς μέθοδοι διαχeίρισης των κοπροσωρών που τις καθιστούν υγeιονομικά και πeριβαλλοντολογικά ασφαλeίς. Eπί πλέον, παρουσιάζeται το νομικό πλαίσιο σe eθνικό και eυρωπαϊκό eπίπeδο που διέπeι τη διαχeίριση και διάθeση των κοπροσωρών.

Soil Contamination Rate, Prevalence, Intensity of Infection of Geohelminths and Associated Risk Factors among Residents in Bazou (West Cameroon).

Soil-transmitted helminths (STH) infections remain an important public health problem in the tropics. This study aimed to evaluate the soil contamination rate and prevalence of infestations of geohelminth among residents in Bazou. Four hundred (400) soil samples and 182 stool specimens were collected respectively from four sites and from inhabitants aged 1 to 40 years and above in 12 households. A questionnaire was administered to evaluate risk factors of STH-infections. Soil samples were screened using sucrose centrifugal flotation method while stool specimens were analyzed using two techniques. Out of the 400 soil and 182 stool samples examined, 13(3.3%) and 9(4.95%) were positive respectively after analyses. Soil contamination rates were 2%, 1% and 0.3% for Ascaris, Trichuris and hookworm eggs respectively while 4.95% of stool samples were positive to one species nematode (Ascaris lumbricoides). The soil contamination rate observed (5%) in the rainy season was significantly different (p>0.05) from the one observed (1.5%) in the dry season. Irrespectively of the season, the most frequent parasite identified was Ascaris spp. Soils around houses were more contaminated 6(12%) as compared to those collected from markets 5(10%) and roads 2(4%) while those around classrooms were not contaminated. Participants in the age group of 1-10 were more infected. Factors such as no hand washing habit and untrimmed finger nails were found to be important risk factors for STH. These results suggest the necessity to promote measures that could help to reduce STH infections.

The response of common marmoset immunity against cedar pollen extract.

The in vivo model of pollinosis has been established using rodents, but the model cannot completely mimic human pollinosis. We used Callithrix jacchus, the common marmoset (CM), to establish a pollinosis animal model using intranasal weekly administration of cedar pollen extract with cholera toxin adjuvant. Some of the treated CMs exhibited the symptoms of snitching, excess nasal mucus and/or sneezing, but the period was very short, and the symptoms disappeared after several weeks. The CD4+CD25+ cell ratio in the peripheral blood increased in CMs quickly after the nasal administration of cedar pollen extract, but the timing was not parallel with the symptoms. IL-10 mRNA was enhanced in the peripheral blood mononuclear cells (PBMCs), suggesting CM-induced tolerance for cedar pollen administration. Similarly, Foxp3 mRNA was also detected in the PBMC. Additive sensitization of these CMs with Ascaris egg administration did not enhance chronic inflammation of type 1 allergy to induce the symptoms. These results suggest that the environmental immune cells develop transient allergic symptoms and subsequent immune-tolerance in the intranasally sensitized CMs.

Decentralised black water treatment by combined auto-thermal aerobic digestion and ammonia – A pilot study optimising treatment capacity

Partial heating of black water by auto-thermal aerobic digestion was combined with the addition of 1% w/w urea and monitoring of pathogens and indicator organisms over a 21-day period. After initial mixing, the 160 m3 black water (60 m3 heated and 100 m3 non-heated) was left undisturbed. The urea was confirmed to be fully degraded into ammonia (5.1 g N L−1) first after 14 days, while the pH stabilised at around 9.2 after one week. The initial temperature of 17 °C fell by 6 °C during the study. E. coli and Salmonella spp., which are sensitive to ammonia, were inactivated during the first few days of the study, despite the urea only being partly hydrolysed. At day 14, f-RNA bacteriophages could also no longer be detected. The more persistent somatic coliphages, Enterococcus spp. and Ascaris eggs, showed significant but slow inactivation. The treatment proved to be efficient with regards to salmonella, which is a target pathogen in the Swedish context, but for parasite egg inactivation a higher temperature was required. The treatment would benefit from more frequent stirring to speed up the hydrolysis of urea and thus improve treatment efficiency. The alternative treatment scheme could increase capacity by 2.4 times, albeit with a 40% higher cost per volume due to the increased use of urea.

The time-temperature relationship for the inactivation of Ascaris eggs.

A time–temperature plot presenting the inactivation of Ascaris eggs is expanded with additional literature data. The information is of value to designers and operators of sanitation equipment who have Ascaris inactivation as an objective.

Survival of chicken ascarid eggs exposed to different soil types and fungi

The eggs of intestinal ascarid parasites (Ascaridia galli and Heterakis spp.) of chickens can survive long-term in soil and this makes contaminated yards and pastures infective to chickens for years. The fungi Pochonia chlamydosporia Biotype 10 and Metarhizium brunneum KVL04-57 can kill ascarid eggs in agar assays but their efficacy against these eggs in soil is unknown. We therefore initially tested the ovicidal effect of the two fungi in laboratory soil assays. Unembryonated eggs were added to sterilised and non-sterilised soil with or without fungi, and egg recovery was examined before and after incubation (22°C, 30days). Egg recovery was substantially reduced by P. chlamydosporia and M. brunneum in sterilised soil. However, in non-sterilised soil only M. brunneum slightly reduced egg counts. Notably, egg recovery was reduced markedly in non-sterilised soil though no fungi were applied. To test if this is a general characteristic of natural soil, eggs were incubated in similar assays comprising 7 different soils (sterilised and non-sterilised). After incubation, egg recoveries were reduced substantially in all non-sterilised soils whereas there were only minor reductions in sterilised soils. We next isolated and examined if particular egg-degrading fungi occurred in the non-sterilised soil that had exhibited the most extreme ovicidal activity (99%). The fungal isolates belonged to two genera (Metarhizium and Acremonium) with reported egg-degrading properties but when tested in vitro in agar assay, none of the three tested isolates of native fungi degraded >34% eggs, suggesting that these fungi may not individually have caused the reduction in egg survival in the non-sterilised soil. In conclusion, a range of natural soils showed inherent properties related to biotic factors to degrade nematode eggs. The biocontrol efficacy of both P. chlamydosporia Biotype 10 and M. brunneum KVL04-57 was very good in sterilised soil but currently limited in non-sterilised soil, potentially due to competition with natural soil biota in fungal establishment. Further research may determine if efficacy may be increased by changing the formulation.

Retrieving ascarid and taeniid eggs from the biological remains of a Neolithic dog from the late 9th millennium BC in Western Iran.

BACKGROUND Paleoparasitology reveals the status of parasitic infections in humans and animals in ancient times based on parasitic particles found in biological remains from archaeological excavations. This line of research emerged in Iran in 2013.OBJECTIVE The identification of parasites from Neolithic times is an attractive subject that shows the oldest origins of parasitic infections in a given geographical region. From an archaeological point of view, this archaeological site is well-known for animal domestication and agriculture in ancient Iran.METHODS In this study, soil deposited on the surface and in the pores of a dog pelvic bone was carefully collected and rehydrated using trisodium phosphate solution.FINDINGS The results showed ascarid and taeniid eggs retrieved from the biological remains of a dog excavated at the East Chia Sabz archaeological site, which dates back to the Neolithic period (8100 BC).MAIN CONCLUSION The current findings clearly illustrate the natural circulation of nematode and cestode parasites among dogs at that time. These ancient helminth eggs can also be used to track the oldest parasitic infections in the Iranian plateau and contribute to the paleoparasitological documentation of the Fertile Crescent.

Inactivation of Ascaris Eggs in Human Fecal Material Through In Situ Production of Carboxylic Acids.

Discovering new ways to inactivate pathogens in human waste is critical for the improvement of worldwide access to sanitation and for the reduction of the environmental impact of conventional waste treatment processes. Here, we utilized the carboxylate platform and chain elongation to produce n-butyric acid and n-caproic acid via the anaerobic fermentation of human fecal material. Then, we inactivated Ascaris eggs through exposure to these carboxylic acids. Using batch experiments with human fecal material as substrate, we accumulated n-butyric acid and n-caproic acid at total concentrations (uncharged acid plus conjugate base) of 257 and 27.1 mM, respectively. We then showed that carboxylic acids at these concentrations inactivated Ascaris eggs when the pH was below the pKa for the acids, causing them to exist primarily in the uncharged forms. We observed that uncharged carboxylic acids affected viability rather than the pH itself or conjugate bases. In addition, we modeled the viability of Ascaris eggs as a function of uncharged carboxylic acid concentration for n-butyric acid and n-caproic acid at exposure times of 2, 6, 12, and 20 days. The results presented here indicate that in situ biological production of carboxylic acids in HFM provides a promising method of pathogen inactivation and may lead to new developments in sanitation technology and treatment of fecal sludge.

Following the Worms: Detection of Soil-Transmitted Helminth Eggs on Mothers’ Hands and Household Produce in Rural Kenya

.Approximately one-quarter of the world’s population is infected with at least one species of soil-transmitted helminth (STH). The role of produce and hands in STH transmission is not well understood. We collected and processed mother hand rinse and garden-grown produce rinse samples from 116 rural households in Kakamega, Kenya, in an area previously identified to have high STH egg contamination in household soil. Ascaris was the only STH species detected; 0.9% of hand rinse, 3.5% of leafy produce, and 1.8% of root produce samples had Ascaris eggs. Our results indicate produce and hands can carry Ascaris eggs. However, due to the low detected prevalence of eggs on hands and produce, and a high prevalence of cooking the produce items tested, these pathways might have a minor contribution to STH exposure in this setting.

Morpho-pathological description of first record of fatal concurrent intestinal and renal parasitism in Columba livia domestica in India

Out of around 200 pigeons (housed at Mahendra Chaudhury Zoological Park, Chhatbir, Punjab), two pigeons exhibiting signs of depression, lethargy, droopiness and blood tinged greenish diarrhoea were quarantined for detailed examination. The faecal examination revealed a concurrent parasitic egg load of capillarid, ascarid and strongyle eggs. Morphological observations after clearing of retrieved parasites from the deceased pigeons revealed the presence of Ascaridia columbae, Capillaria obsignata, and Ornithostrongylus quadriradiatus. Histopathological studies of the intestines revealed sloughing and hyperplasia of the lining epithelium; whereas kidneys of one of the pigeon exhibited the extensive tubular damage and marked haemorrhages with cut sections of the parasite, Paratanaisia bragai. The other vital organs showed no signs of any significant lesions in both pigeons. This seems to be the first report of fatal concurrent gastrointestinal and renal pathology due to A. columbae, C. obsignata, O. quadriradiatus and P. bragai in pigeons kept at zoological park in India.

Morpho-pathological description of first record of fatal concurrent intestinal and renal parasitism in Columba livia domestica in India

Out of around 200 pigeons (housed at Mahendra Chaudhury Zoological Park, Chhatbir, Punjab), two pigeons exhibiting signs of depression, lethargy, droopiness and blood tinged greenish diarrhoea were quarantined for detailed examination. The faecal examination revealed a concurrent parasitic egg load of capillarid, ascarid and strongyle eggs. Morphological observations after clearing of retrieved parasites from the deceased pigeons revealed the presence of Ascaridia columbae, Capillaria obsignata, and Ornithostrongylus quadriradiatus. Histopathological studies of the intestines revealed sloughing and hyperplasia of the lining epithelium; whereas kidneys of one of the pigeon exhibited the extensive tubular damage and marked haemorrhages with cut sections of the parasite, Paratanaisia bragai. The other vital organs showed no signs of any significant lesions in both pigeons. This seems to be the first report of fatal concurrent gastrointestinal and renal pathology due to A. columbae, C. obsignata, O. quadriradiatus and P. bragai in pigeons kept at zoological park in India.

Segregated settlements present an increased risk for the parasite infections spread in Northeastern Slovakia

Summary The occurrence of parasitic infections among the children, dogs and its association with soil contamination in two villages with different hygiene level standards were analysed. Infections were present in both examined localities, but in the village with higher living standard, a better personal and communal hygiene level and better dogs care a lower occurrence of parasitic germs in soil was detected. High prevalence of protozoa and helminths was observed not only within canine population but also in children throughout the year in the village with lower hygiene and socio-economic standard. We have identified up to 12 taxa of parasites in 127 collected dogs’ excrements and mean prevalence was 71.65 %. The most frequent were eggs of family Ancylostomatidae and Ascaris spp., followed by Toxocara canis, Toxascaris leonina, Giardia duodenalis cysts, Isospora spp. oocysts, eggs of Capillaria aerophila, Trichuris vulpis, Taenia type eggs, Dipylidium caninum, oocysts of Sarcocystis spp. and larvae of Angiostrongylus vasorum. The soil samples collected near dwellings were highly contaminated. Two thirds of samples contained eggs for the most part of family Ancylostomatidae as well as genera Ascaris and Toxocara. Among the kids population helminth ova were present in 53.17 % of stool samples, where the eggs of Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Hymenolepis diminuta and cysts of G. duodenalis were the most frequent. In contrast, parasitic diseases were not seen in children population living in the locality with common hygiene standard.

Study of Biochemical and Microbiological Properties During Co-composting of Spent Mushroom Substrates and Chicken Feather

To study the biochemical and microbiological properties during co-composting of chicken feather and spent mushroom substrates, chicken feather by incubation of multiple microorganisms were co-composted for 28 days with Pleurotus geesteranus-degraded Eucalyptus sawdust (PE), P. geesteranus-degraded weed tree sawdust (PW) and Ganoderma lucidum-degraded weed tree sawdust (GW), respectively. Characteristics of physico-chemical, enzymatic and microbiological parameters during composting were investigated in terms of temperature, pH, moisture, activities of CMCase, and succession of bacteria and fungus. Results showed that the peak temperature in PEC was 59 °C on 5 days. No ascaris egg was detected in the final composts of PEC, PWC and GWC. The pH of compost in PEC and GWC were about 8.5, which was higher than pH of compost in PWC 7.4. The activities of CMCase in PEC were significantly higher than PWC and GWC during composting. The OM and C/N on 28 days decreased compared to the raw materials. The PCR-DGGE profiles showed significant differences in structure of bacteria and fungus after composting. Four prominent species of bacteria were replaced by uncultured bacterium and the prominent species of fungus were thermophiles and cellulolytic strains on 28 days. Correlation properties were similarly shared by the physico-chemical parameter and bacteria as well as fungus.

Monitoring results of soil-transmitted nematodiasis in national surveillance site of Huaiyang County in Henan Province, 2006-2015

To understand the epidemic situation of soil-transmitted nematodiasis in the national surveillance site in Henan Province. Over 1 000 fecal samples from inhabitants in Huaiyang County of Henan Province, which was a national surveillance site, were collected each year from 2006 to 2015, the eggs of soil-transmitted nematodes and other intestinal helminths were examined by Kato-Kats technique. The cellophane swab method was used to detect Enterobius vermicularis eggs in children aged 3 to 12 years. In addition, the soil samples were collected from vegetable fields, lavatories, courtyards and kitchens of 10 families randomly selected in each year to examine Ascaris eggs by a modified saturated sodium nitrate floatation method. From 2006 to 2015, 10 419 persons were investigated, and the eggs of five species of intestinal helminths, Ascaris lumbricoides, Trichuris trichiura, hookworm, E. vermicularis, and Trichostrongylus orientalis, were detected, The average infection rate of soil-transmitted nematodes in residents in Huaiyang County was 3.69%. The intensity of infection was mild and a family clustering was obvious. Both the infection rates of E. vermicularis in children and soil-transmitted nematodes in villagers had no significant differences between different genders (both P＞0.05). The infection rates of soil-transmitted nematodes, A. lumbricoides and E. vermicularis all reached the highest in the age group of 1-10 years. For different education back-ground, the people with primary school education had the highest infection rate, and the infection rate showed a decreasing trend with the increase of the educational level. The infection rate of soil-transmitted nematodes in the national surveillance site in Henan Province showed a decreasing trend from 2006 to 2015. Unfertilized and fertilized A. lumbricoides eggs were detected in the soil samples, but the positive rate was very low. In the recent 10 years, the infection rate of soil-transmitted nematodes in the national surveillance site in Henan Province shows a decreasing trend and maintains at a low level. The infection shows a family clustering. The children, especially those aged 3-9 years are the main infected population, and E. vermicularis infection is the key point of prevention and control.

Reduced efficacy of albendazole against Ascaris lumbricoides in Rwandan schoolchildren

Control of human soil-transmitted helminths (STHs) relies on preventive chemotherapy of schoolchildren applying the benzimidazoles (BZ) albendazole or mebendazole. Anthelmintic resistance (AR) is a common problem in nematodes of veterinary importance but for human STHs, information on drug efficacy is limited and routine monitoring is rarely implemented. Herein, the efficacy of single dose albendazole (400 mg) was evaluated in 12 schools in the Huye district of Rwanda where Ascaris is the predominant STH. Ascaris eggs were detected by wet mount microscopy and the Mini-FLOTAC method to assess cure rate (CR) and faecal egg count reduction (FECR). Blood and faecal samples were analysed for co-infections with Plasmodium sp. and Giardia duodenalis, respectively. Ascaris positive samples collected before and after treatment were analysed for putatively BZ-resistance associated β-tubulin gene single nucleotide polymorphisms. The overall CR was 69.9% by Mini-FLOTAC and 88.6% by wet mount microscopy. The FECR was 75.4% and the 95% calculated confidence intervals were 50.4–87.8% using sample variance, 55.4–88.8% by bootstrapping, and 75.0–75.7% applying a Markov Chain Monte Carlo Bayesian approach. FECR varied widely between 0 and 96.8% for individual schools. No putative BZ-resistance associated polymorphisms were found in the four Ascaris β-tubulin isotype genes examined. Since FECRs <95% indicate reduced efficacy, these findings raise the suspicion of BZ resistance. In the absence of respective molecular evidence, heritable AR in the local Ascaris populations cannot be formally proven. However, since FECRs <95% indicate reduced efficacy, BZ resistance may be suspected which would be alarming and calls for further analyses and routine monitoring in preventive chemotherapy programs.