Trichuris Species Research Articles

Prevalence and diversity of gastrointestinal parasites in long-tailed macaques at Kosamphi Forest Park, Kumphawapi Monkey Garden, and Dong Ling Don Chao Pu Park, North-east Thailand.

These three parks in North-east Thailand, Kosamphi Forest Park, Kumphawapi Monkey Garden, and Dong Ling Don Chao Pu Park, are internationally recognized for sheltering long-tailed macaques. Overfeeding by tourists and locals significantly increases the frequency of human-macaque encounters. Being close to each other raises the chances of contracting gastrointestinal (GI) parasites. This study was designed to estimate the prevalence and range of GI parasite infections in long-tailed macaques among the three major natural habitats. Three hundred fecal samples were collected from long-tailed macaques, with 100 samples from each of the three study sites. The samples underwent Formalin-ethyl acetate concentration technique examination. Parasites were identified based on their morphology and size as observed under a light microscope. About 66.67% of the population had GI parasitic infection. Balantidium coli had the highest occurrence (41.66%), whereas Strongyloides spp. (24.33%), Trichuris spp. (18.33%), Entamoeba coli (10.33%), and Endolimax nana (2.33%) followed next in prevalence. A higher rate of single infections (41%) was reported compared to mixed infections (25.66%). At Dong Ling Don Chao Pu Park, the prevalence rate of B. coli in long-tailed macaques was 70%, markedly higher than those reported at the other two study sites. In these areas, the first known case of B. coli infection occurred in long-tailed macaques. In the Kumphawapi Monkey Garden, the prevalence of Strongyloides spp. and Trichuris spp. infections was significantly greater (45% and 28%, respectively) compared to the other two areas. In northeast Thailand, long-tailed macaques are predominantly infected with B. coli, causing GI protozoal infections. In this primate population of the region, Strongyloides and Trichuris species are common helminths. This study offers new knowledge on parasitic loads in Thai long-tailed macaques, essential for devising effective One Health approaches to prevent and manage zoonotic diseases.

A combined amplicon approach to nematode polyparasitism occurring in captive wild animals in southern China

BackgroundGastrointestinal tract (GIT) nematodes prefer to live in the intestines of wild animals, causing damage and even death, and posing a zoonotic risk. The polyparasitism of GIT nematodes results in the complex dynamics of the nematode communities that occur naturally in wild animals. However, the nematode community in captive wild animals is poorly understood.MethodsWe combined microscopic examination and amplicon sequencing for community diversity.ResultsWe characterized GIT nematode assemblages to one order, one family, four genera, and ten species, in 512 fecal samples of 121 species from captive wild animals in southern China. The positive rate of GIT nematodes was 20.7% (106/512), including 42.3% (11/26) in reptiles, 26.5% (39/147) in herbivores, 25.0% (25/100) in non-human primates, 20.0% (5/25) in omnivores, 12.2% (9/74) in carnivores, and 12.1% (17/140) in avians. The dominant nematodes were Haemonchus contortus in herbivores and Trichuris species in primates. The nematode communities of arboreal primates differed from their terrestrial counterparts, reflecting both host phylogeny and ecological constraints. Soil-transmitted Strongyloides species were widespread throughout the herbivore, primate, avian, and carnivore communities, and tended to infect omnivorous primates and terrestrial herbivores. In addition, new Trichuris and Heterakis species were found in the nematode communities of captive porcupines and peafowls.ConclusionThis study highlights the variation in the composition of the GIT nematode community and strengthens the attention to the harms induced by zoonotic nematodes and co-infective nematodes with low species richness.Graphical

Prevalence of Parasitic Contamination of Vegetables Sold in Dutsin-Ma Markets, Katsina State, Nigeria

This study was carried out to determine the prevalence of parasitic contamination of vegetables sold in Dustin-Ma markets, Katsina State. A total of 270 vegetables including of lettuce, cabbage, spinach and sesame were obtained from three selected markets (Kasuwann Laraba, Kasuwann Aminu and Kasuwann Kadangaru), and examined for presence of parasitic eggs, cyst, larvae and worms by using using sedimentation method methods. This study found that of 88.9% of the vegetables sold in Dustin-ma markets tested positive for the presence of parasite contamination. The distribution of specific parasites among positive samples reveals the presence of Ascaris species 65(24.1%), hookworm 39(14.4%), Trichuris species 16(5.9%), Taenia species 23(8.5%), Hymenolepsis species 6(2.2%), Enterobius vermicularis 25(9.3%), Fasciola species 13(4.8), Toxocara species 4(1.5%) and Strongyloides stercoralis 49(18.1%). The lettuce, cabbage, spinach and sesame samples were contaminated with helminthic parasites with 27.1%, 28.8%, 27.1% and 17.1% respectively. Vegetable samples from Kasuwann Laraba had the highest prevalence of 85(31.5%), and Kasuwan Aminu with a total prevalence of 78(28.9%), while Kasuwann Kadangaru had the lowest prevalence with a total prevalence of 77(28.5%) at P < 0.05. Vegetables are important constituents of healthy diet and people have been encouraged to eat lots of raw (fresh) vegetables and these can serve as vehicles of transmitting enteric parasitic pathogens throughout the process of planting to consumption. Proper washing of vegetable is imperative, improve Sanitation and Hygiene Practices and Health Education are necessary for managing the prevalence of geohelminth parasites.

Effective removal of Helminths Ova from wastewater and its inactivation from sewage sludge using thermophilic anaerobic digestion

Treated wastewater became a sustainable alternative to reuse for irrigation and household purpose. The presence of pathogens, i.e., viable Helminths Ova (viable HO) might become a serious health issue for the safe use of the treated wastewater. HO represents an important challenge to environmental engineering as they are among the most difficult biological parasites to remove from wastewater and inactivate in sludge. In light of this, the current study thoroughly investigated the presence and destruction of active HO in field full-scale municipal wastewater using pressurized sand filtration (PSF) and lab-scale thermophilic anaerobic digestion (TAD) process. The presence of HO as 16 Ova/L in wastewater and 35 Ova/L in sewage sludge were identified. Upon further species identification, the major species of HO, such as, Ascaris (70.83 %), Trichuris (12.50 %), Hymenolepis (12.50 %), and Toxocara (4.17 %) were detected. The maximum HO removal of 100 % and TSS removal of 97.14 % from the wastewater were noticed with the use of cost-effective PSF technique. Moreover, a significant inactivation efficiency of 51.43 % was observed from sewage sludge using TAD over a period of 60 days. The maximum COD and TSS removal of 34 % and 60.35 %, respectively, was noticed in the TAD process. The study showed that TAD could be an effective pre-treatment step for the destruction of viable HO. The PSF and TAD combined technology could contribute to municipal wastewater treatment in a sustainable way to improve environmental protection, resource recovery and public health protection.

Trichurid nematodes from South American Camelid: an approach to native assemblages through the parasitology of archaeological sites.

To gain insights into the trichurid diversity in pre-Hispanic remains of South American camelids (SACs), as well as into modern SAC populations, a bibliographic search was carried out to find parasitological studies. Results showed that a total of 17 studies were performed at archaeological and paleontological sites, in which a total of 213 samples were examined. The sample set was used as the unit of analysis, and 83% of 52 pre-Hispanic sample sets were positive for parasites. Parasitological studies confirmed the pre-Hispanic presence of diverse trichurids: two Trichuris species and capillariid eggs with morphological differences that allowed them to be assigned to three different species. Currently, the richness of the native trichurid assemblages in SACs has been extended by the inclusion of two species (Trichuris sp. 2 and Capillariinae gen. sp. 1). Modern T. tenuis Chandler, 1930, considered SAC-specific, would have invaded SAC populations during the European colonization. The estimate of regional and temporal trichurid prevalence and paleoecological information allowed us to propose a possible origin for some of them. Although the present analysis is exploratory, it should stimulate future studies about the biogeographic history of SAC helminths, provide relevant information to improve descriptions of the Holocene ecology, and identify threatened helminths.

Morphological and molecular characterization of Trichuris muris (Nematoda: Trichuridae): studies from two commensal rodent species.

In this paper we re-describe Trichuris muris based on morphological data following isolation from two commensal rodent species, Mus musculus from Mexico and Rattus rattus from Argentina. Furthermore, we provide a molecular characterization based on mitochondrial (cytochrome c oxidase subunit 1 mitochondrial gene) and nuclear (internal transcribed spacer 2 region) markers in order to support the taxonomic identification of the studied specimens of T. muris from M. musculus. We distinguished T. muris from 29 species of Trichuris found in American rodents based on morphological and biometrical features, such as the presence of a spicular tube, length of spicule, size of proximal and distal cloacal tube and non-protrusive vulva. We suggest that spicular tube patterns can be used to classify Trichuris species in three groups. Considering that the diagnosis among the species of this genus is mainly based on morphometry, this proposal represents a relevant contribution. We provide molecular studies on two markers, making this the first contribution for T. muris in the Americas. This study makes an important contribution to the integrative taxonomy of cosmopolitan nematode species, and its correct determination from the parasitological study of commensal rodents.

Prevalences and Characteristics of Trichuris Spp. Infection in Sheep in Pastoral Areas of the Tianshan, Xinjiang, China.

Nematodes of the Trichuris genus are commonly reported parasites that can cause trichuriasis in many animals, which leads to inflammation, intestinal bleeding and reductions of productivity in livestock. Knowledge of the prevalence of Trichuris infestation in the Tianshan ovine population and of the nematode species parasitising the population is not exhaustive, and this study aimed to expand the knowledge. A total of 1,216 sheep slaughtered in five pasture areas in the Tianshan Mountains of Xinjiang were investigated and a phylogenetic analysis based on the mitochondrial cox1 gene was performed to clarify the genetic relationships of the various Trichuris species. Sheep totalling 1,047 were infected with Trichuris spp. establishing the rate at 86.1%. Using a morphological protocol, six documented and one undefined species were identified, namely T. gazellae, T. lani, T. ovina, T. longispiculus, T. concolor, T. discolor and Trichuris sp. Among them, T. gazellae and T. lani were the dominant species, accounting for 34.5% and 31.0% of Trichuris spp., respectively. Phylogenetic analysis divided the detected species of Trichuris spp. into two genetic clades (clade I and clade II). The six documented species that can infect sheep and the undefined species were clustered into clade I, with inter- and intra-species genetic diversity apparent. This survey described in detail the morphological characteristics of six known and one undefined species of Trichuris, which not only enriched the taxonomic information on record regarding Trichuris spp., but also provided valuable epidemiological data for the prevention and control of trichuriasis in sheep.

Clostridia isolated from helminth-colonized humans promote the life cycle of Trichuris species.

Soil-transmitted intestinal worms known as helminths colonize over 1.5 billion people worldwide. Although helminth colonization has been associated with altered composition of the gut microbiota, such as increases in Clostridia, individual species have not been isolated and characterized. Here, we isolate and sequence the genome of 13 Clostridia from the Orang Asli, an indigenous population in Malaysia with a high prevalence of helminth infections. Metagenomic analysis of 650 fecal samples from urban and rural Malaysians confirm the prevalence of species corresponding to these isolates and reveal a specific association between Peptostreptococcaceae family members and helminth colonization. Remarkably, Peptostreptococcaceae isolated from the Orang Asli display superior capacity to promote the life cycle of whipworm species, including hatching of eggs from Trichuris muris and Trichuris trichiura. These findings support a model in which helminths select for gut colonization of microbes that support their life cycle.

The Use of MALDI-TOF MS as a Diagnostic Tool for Adult Trichuris Species.

Trichuriasis is considered a neglected tropical disease, being the second most common helminthiasis in humans. Detection of Trichuris in routine diagnosis is usually done by microscopic detection of eggs in fecal samples. Other molecular analyses are more reliable and could be used, but these analyses are not routinely available in clinical microbiology laboratories. The use of matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) is increasing since the last decades due to its recent evidence as a potential role for reliable identification of microorganisms and a few nematodes. But, for parasites detection, normalized protocols and the acquisition and introduction of new species to the database are required. We carried out a preliminary study confirming the usefulness of MALDI-TOF MS for the rapid and reliable identification of Trichuris suis used as control and the creation of an internal database. To create main spectra profiles (MSPs), the different parts of five whipworms (esophagus and intestine) were used, developing different tests to verify the repeatability and reproducibility of the spectra. Thus, to validate the new internal database, 20 whipworms, separating the esophagus and intestine, were used, of which 100% were accurately identified as T. suis, but could not distinguish between both parts of the worm. Log score values ranged between 1.84 and 2.36, meaning a high-quality identification. The results confirmed that MALDI-TOF MS was able to identify Trichuris species. Additionally, a MALDI-TOF MS profile of T. suis proteome was carried out to develop the first internal database of spectra for the diagnosis of trichuriasis and other Trichuris spp.

Epidemiological Risk Factors and Progression of Gastrointestinal Parasitic Infestation among Food Animals of Bangladesh: A Systematic Review and Meta-analysis

The gastrointestinal parasitic infestation seems to have a substantial economic impact on the entire livestock production industry. Because of the parasites' environmental appropriateness, numerous domestic animals in Bangladesh are particularly susceptible to the infestation; however, the extent to which people are aware of the potential risk factors is debatable. Therefore, the current meta-analysis' objective is to determine the precise understanding of potential risk variables and the impact of climatological variations on five important gastrointestinal parasites: Paramphistomum species, Strongyloides species, Trichuris species, Schistosoma species, and Moneizia species. Four globally recognized databases, including Web of Science, Scopus, PubMed, and Google Scholar were screened to choose the studies published in English language from 2000 to 2020. Finally, 29 studies were selected for further analysis and recorded the maximum prevalence in Paramphistomum species (26%; 95% CI: 19-33), followed by Strongyloides species (9%, 95% CI: 5-12), Trichuris species (10%, 95% CI: 4-17), Schistosoma species (19%, 95% CI: 7-31), and Moneizia species (8%, 95% CI: 5-10); besides the overall prevalence was noted as 15% (95% CI: 11-18). Furthermore, subgroup analysis revealed that parasite infestation was most prevalent in females (21%) and the elderly animal population (14%) and the summer season (26%). To sum up, the current meta-analysis visualized the epidemiological risk factors with the overall incidence of five major parasite infestations in livestock animals in Bangladesh; hence, the government and shareholders may employ it as proof before launching any control programs or improving farmers' awareness.

Ectoparasites and endoparasites of goats in Port Harcourt, Rivers State, Nigeria

Parasitological problems can affect goats’ productivity, skin quality and be of zoonotic importance. This study determined the prevalence of ectoparasite and endoparasites in goats in Port Harcourt. A total of 150 animals were examined from four different locations. Ectoparasites were detected by brushing and examining with naked eyes, hand lens, and under the microscope. Endoparasites were detected by standard parasitological technique. Results indicate that ectoparasites were higher (61.3%) in goats than endoparasites (38.6%). Based on location, ectoparasites prevalence was higher in Uniport Agric farm (30.4%), this was followed by Mile 3 with (25.1%) while Rumuosi and Alakahia had 22.8% and 21.6% respectively. Endoparasites were higher (33.2%) at Uniport Agric farm, followed by Mile 3, (24.6%) then Rumuosi and Alakahia had (22.6%) and (19.5%) respectively. Ectoparasites identified were Caliseta species (38.1%), Demodex species (20.6%), while Ixodes species, Damalimia species, and Ctemacephalides species had (16.9%), (14.0%) and (10.3%). Endoparasites identified were Nimatodirus (41.0%), Trichuris species (23.8%), Moneiza species (22.3%), and Ascaris species (12.85). In conclusion, the prevalence of ectoparasites and endoparasites in Port Harcourt is relatively high. An awareness campaign about the importance and control of these parasites is recommended to forestall zoonosis risks.

Characterization of trichuris species from porcupine (Hystrix cristata) at zoological garden of Spain

Population of Trichuris sp. isolated from Hystrix cristata was analyzed based on morphological, biometrical characteristics and mitochondrial (cox1, cob, rrnL) and ribosomal (ITS1) (rDNA) region sequences. Morphological and biometrical results revealed that Trichuris sp. from H. cristata present a high similarity with Trichuris landak from Hystrix javanica and less similarity with other Trichuris species from porcupine species (Trichuris hystricis, Trichuris lenkorani and Trichuris mettami). The lack of molecular data corresponding to Trichuris species that parasitize the porcupine (genus Hystrix and Atelerix) has not allowed a comparative molecular or phylogenetic study. Molecular analyses revealed the existence of two different haplotypes that did not correspond to different morphospecies. Relationships among Trichuris sp. from H. cristata and other Trichuris spp. have been resolved by molecular sequence data in this study. Thus, the combined analysis of one ribosomal and three mitochondrial markers revealed a sister relationship between whipworms parasitizing porcupine and other Trichuris spp. from rodents and canids and separated from the rest of Trichuris spp. from other hosts species. It is necessary accurate information on the possible zoonotic behavior of different Trichuris species for health workers to improve existing control measures. Thus, it is necessary to increase the studies of integrative taxonomy on Trichuris spp. based on morphological, biometrical and molecular data, which will inevitably contribute to our knowledge on the etiology of trichuriasis.

Trichuriasis in Selected Deer (Cervidae) Species: A Geographical Perspective

Trichuris spp. are endoparasites found in a wide range of mammalian species. Some of these host species include humans, non-human primates, dogs, cats, pigs, wild ruminants and domesticated ruminants. However, it had been noted that Trichuris are host specific, therefore the parasites that infects wild ruminant species may be transmitted to domesticated animals such as cattle, sheep and goat. Thus, the aim of this review was to identify species of Trichuris that parasitise deer species and to categorise the prevalence of this disease at various geographical locations. It must be noted that the prevalence and intensity of this parasite within deer species was low and rarely showed any signs of clinical disease. However, deer can be a source of infection to domesticated ruminants that may be housed in closed proximity. The review is divided into several sections based on the geographical location of the deer species. In summary, the review shows that most of the identification of various species of Trichuris in deer is based on morphological techniques. However, the use of molecular techniques in the identification of various species of Trichuris is more accurate. In closing, there is a need for more molecular investigations to be done in identifying the species of Trichuris that are present in deer living in the neo-tropical region.

Soil-Transmitted Helminths: Parasite load and viability amidst mass drug administration in Ibadan, Southwestern Nigeria

Presently, the operational strategies for the control of Soil-Transmitted Helminths (STHs) has been via Mass Drug Administration (MDA) which primarily targets school and pre-school age children, child-bearing age women, including adults with high-risk occupations. Therefore, this study was done to relate the frequency of drug usage by the host to the intensity and viability of STH ova in the faecal samples collected in 11 study areas (Alakia, Akanran, Molete, Aleshinloye, Iwo Road, Eleyele, Bodija, Moniya, Olodo, Omi Adio and Podo) within Ibadan methropolis. A total of 1100 faecal samples were collected from voluntary participants between January and December 2018 and a standard Kato-Katz techniques was used for diagnosis. Well-structured questionnaire to acquire data on the demographics and usage of drug against STH infections was administered to each of the consenting participants. SPSS version 21 was used to analyze the data; ANOVA at p< 0.05. Faecal samples (35.9%) had one species of parasite minimally. Ascaris had the highest prevalence of 41.6%, followed by 24.5%, 23.5% and 10.4% for Trichuris, hookworm and Strongyloides species respectively. The parasite specific prevalence varied significantly (p≤0.05). Bodija had the highest frequency of drug usage with the least viability (6.1%) and intensity (5.4%). There is a negative correlation between frequency of drug usage and intensity (r= -0.39) and viability (r= -0.35) across the sampling locations. The STH infection prevalence observed could be attributed to poor environmental sanitation, poor personal hygiene arising from several factors such as lack of adequate sanitary facilities and other associated risk in the study locations. The decrease in viability and intensity of STH with respect to level of MDA drug usage might be significant to anticipated effectiveness and eventual success of MDA programmes in Ibadan environs.

Occurrence of gastrointestinal helminths and the first molecular detection of Ancylostoma ceylanicum, Trichuris trichiura, and Trichuris vulpis in dogs in Myanmar.

Dogs may serve as hosts for a variety of zoonotic or potentially zoonotic helminths, including Ancylostoma ceylanicum and Trichuris species. Cross-sectional study design was used to collect 210 faecal samples of dogs from Nay Pyi Taw area, Myanmar. According to microscopic examination, 180 samples (85.7%) were positive for eight species of gastrointestinal helminths. Among them, positive rates of Ancylostoma species and Trichuris species eggs were observed as 79.0% (166/210) and 11.9% (15/210), respectively. Molecular identification of A. ceylanicum and Trichuris species was confirmed by COX1 gene- and SSU rRNA gene-targeted PCR. Partial sequences of COX1 and SSU rRNA showed 100% identity with A. ceylanicum, Trichuris trichiura, and Trichuris vulpis deposited in GenBank.

Functional Characterization of the Oxantel-Sensitive Acetylcholine Receptor from Trichuris muris.

The human whipworm, Trichuris trichiura, is estimated to infect 289.6 million people globally. Control of human trichuriasis is a particular challenge, as most anthelmintics have a limited single-dose efficacy, with the striking exception of the narrow-spectrum anthelmintic, oxantel. We recently identified a novel ACR-16-like subunit from the pig whipworm, T. suis which gave rise to a functional acetylcholine receptor (nAChR) preferentially activated by oxantel. However, there is no ion channel described in the mouse model parasite T. muris so far. Here, we have identified the ACR-16-like and ACR-19 subunits from T. muris, and performed the functional characterization of the receptors in Xenopus laevis oocytes using two-electrode voltage-clamp electrophysiology. We found that the ACR-16-like subunit from T. muris formed a homomeric receptor gated by acetylcholine whereas the ACR-19 failed to create a functional channel. The subsequent pharmacological analysis of the Tmu-ACR-16-like receptor revealed that acetylcholine and oxantel were equally potent. The Tmu-ACR-16-like was more responsive to the toxic agonist epibatidine, but insensitive to pyrantel, in contrast to the Tsu-ACR-16-like receptor. These findings confirm that the ACR-16-like nAChR from Trichuris spp. is a preferential drug target for oxantel, and highlights the pharmacological difference between Trichuris species.

Immunoregulatory molecules secreted by Trichuris muris.

Trichuris, whipworm nematode infections are prevalent in humans, domestic livestock and mammals. All share an epithelial dwelling niche and similar life cycle with the chronic infections that follow implying that immune evasion mechanisms are operating. Nematode excretory secretory (ES) products have been shown to be a rich source of immunomodulatory molecules for many species. The Trichuris muris model is a natural parasite of mice and has been used extensively to study host–parasite interactions and provides a tractable platform for investigation of the immunoregulatory capacity of whipworm ES. The present review details progress in identification of the composition of T. muris ES, immunomodulatory components and their potential mechanisms of action. The adult T. muris secretome is dominated by one protein with modulatory capacity although remains to be completely characterized. In addition, the secretome contains multiple other proteins and small molecules that have immunomodulatory potential, certainly by comparison to other Trichuris species. Moreover, T. muris-derived exosomes/exosome-like vesicles contain both protein and multiple miRNAs providing an alternate delivery process for molecules with the potential to modulate host immunity.

Epidemiology of gastrointestinal worm infections in pigs reared in Enugu State, Nigeria.

The online version contains supplementary material available at 10.1007/s12639-021-01377-y.

Complete Mitochondrial Genome of Trichuristrichiura from Macaca sylvanus and Papio papio.

Trichuriasis is among the most prevalent worldwide parasitism caused by helminths. For many years, Trichuris spp. have been described with a relatively narrow range of both morphological and biometrical features. The use of the complete mitochondrial genome (mitogenome) is an alternative and powerful molecular method for inferring phylogenies. Here, we present an overview of the contributions of mitogenome for Trichuris spp. from human and non-human primates. In addition, we carry out structural and phylogenetic comparative analyses with genomes of Trichuris species available in public datasets. The complete mt genomes of Trichuris trichiura and Trichuris sp. from Macaca sylvanus and T. trichiura from Papio papio are 14,091 bp, 14,047 bp and 14,089 bp in length, respectively. The three mt genomes are circular and consist of 37 genes—13 PCGs (cox1–3, nad1–6, nad4L, atp6, atp8 and cob), 22 transfer RNA genes (tRNAs), and two rRNAs (rrnL and rrnS). The molecular evidence presented here supports the hypothesis that T. trichiura de M. sylvanus (TMF31) and T. trichiura de P. papio (TPM1) were similar but genetically different with respect to Trichuris sp. from macaques (TMM5). The phylogenetic study also supported the evolution of the different Trichuris species. In conclusion, we suggest the existence of two cryptic species parasitizing M. sylvanus.

α-Gal specific-IgE prevalence and levels in Ecuador and Kenya: Relation to diet, parasites, and IgG4

IgE to α-Gal is a cause of mammalian meat allergy and has been linked to tick bites in North America, Australia, and Eurasia. Reports from the developing world indicate that α-Gal sensitization is prevalent but has been little investigated. We sought evidence for the cause(s) of α-Gal sensitization and lack of reported meat allergy among children in less developed settings in Ecuador and Kenya. IgE to α-Gal and total IgE were assessed in children from Ecuador (n= 599) and Kenya (n= 254) and compared with children with (n= 42) and without known (n= 63) mammalian meat allergy from the southeastern United States. Information on diet, potential risk factors, and helminth infections was available for children from Ecuador. IgG4 to α-Gal and antibodies to regionally representative parasites were assessed in a subset of children. In Ecuador (32%) and Kenya (54%), α-Gal specific IgE was prevalent, but levels were lower than in children with meat allergy from the United States. Sensitization was associated with rural living, antibody markers of Ascaris exposure, and total IgE, but not active infections with Ascaris or Trichuris species. In Ecuador, 87.5% reported consuming beef at least once per week, including 83.9% of those who had α-Gal specific IgE. Levels of α-Gal specific IgG4 were not high in Ecuador, but were greater than in children from the United States. These results suggest that in areas of the developing world with endemic parasitism, α-Gal sensitization is (1) common, (2) associated with Ascaris exposure, and (3) distinguished by a low percentage of specific/total IgE compared with individuals with meat allergy in the United States.