Search Results (130)

Background/Objectives: Undernutrition and intestinal parasitic infections are critical public health problems in low-income countries, with adverse effects on child growth and increasing anaemia. Madagascar, with a high prevalence of these factors, lacks comprehensive studies analysing their interaction. This study aimed to assess the nutritional status, the prevalence of anaemia, and the occurrence of intestinal parasitic infections among children and adolescents in three southern regions of Madagascar. Methods: A cross-sectional, prospective study of 289 children and adolescents (10–18 years) from three schools located in Antsoamadiro, Fianarantsoa, and Toliara was conducted. Sociodemographic, anthropometric, and haemoglobin concentration data, as well as faecal samples, were collected. Nutritional status was assessed by Nutrimetry, combining Height-for-Age and BMI-for-Age indicators. Stool samples were analysed by optical microscopy and molecular methods. Results: Nutricode 1 (short stature/stunting + thinness/wasting) was significantly more frequent in Toliara. Nutricode 1 was also significantly more prevalent in males than females. Anaemia affected 57.8% of participants and was significantly associated with Nutricode 1. The overall parasitism rate was also associated with Nutricode 1. Trichuris trichiura and Ascaris lumbricoides significantly increased the risk of stunting, wasting, and Nutricode 1. Co-infection with Trichuris trichiura + Giardia duodenalis was significantly associated with wasting and Nutricode 1. This co-infection was also related to the presence of anaemia, as was moderate-intensity infection with T. trichiura. Conclusions: There is a high co-burden of undernutrition, anaemia, and parasitic infections in southern Madagascar. These findings highlight the urgency of implementing comprehensive health programmes combining parasite control, nutritional support, and iron supplementation adapted to regional realities. Full article

Limited molecular data exist on zoonotic parasites Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in Angus calves from Guizhou, China. This study constitutes the first molecular epidemiological survey of these pathogens in this region. 817 fecal samples from Angus calves across 7 intensive beef farms (Bijie City). Nested PCR methods targeting SSU rRNA (Cryptosporidium spp.), gp60 (Cryptosporidium bovis subtyping), bg/gdh/tpi (G. duodenalis), and ITS (E. bieneusi) coupled with DNA sequencing were employed. DNA sequences were analyzed against the NCBI. database. Statistical differences were assessed via a generalized linear mixed-effects model. Cryptosporidium spp. prevalence 23.5% (192/817; 95% CI 28.1–34.6%), with C. bovis predominating 89.6% (172/192; 95% CI 84.4–93.5%) and six subtypes (XXVIa-XXVIf). Highest infection in 4–8-week-olds 29.9% (143/479; 95% CI 25.8–34.1%) (p < 0.01). G. duodenalis: 31.3% (256/817; 95% CI 28.1–34.6%) positive, overwhelmingly assemblage E 97.6% (6/256; 95% CI 0.9–5.0%), zoonotic assemblage A was marginal 0.7% (6/817; 95% CI 0.3–1.6%). Farm-level variation exceeded 10-fold (e.g., Gantang: 55.0% (55/100; 95% CI 44.7–65.0%) vs. Tieshi: 4.9% (5/102; 95% CI 1.6–11.1%). E. bieneusi: prevalence 19.7% (161/817; 95% CI 17.0–22.6%), exclusively zoonotic genotypes BEB4: 49.7% (80/161; 95% CI 41.7–57.7%); I: 40.4% (65/161; 95% CI 32.7–48.4%). Strong diarrhea association (p < 0.01) and site-specific patterns (e.g., Guanyindong: 39.2%). While Giardia exhibited the highest prevalence (31.3%) with minimal zoonotic risk, Enterocytozoon—despite lower prevalence (19.7%)—posed the greatest public health threat due to exclusive circulation of human-pathogenic genotypes (BEB4/I) and significant diarrhea association, highlighting divergent control priorities for these enteric parasites in Guizhou calves. Management/Public health impact: Dominant zoonotic E. bieneusi genotypes (BEB4/I) necessitate: 1. Targeted treatment of 4–8-week-old Angus calves. 2. Manure biofermentation (≥55 °C, 3 days), and 3. UV-disinfection (≥1 mJ/cm²) for karst water to disrupt transmission in this high-humidity region. Full article

Zoonotic opportunistic enteric protozoa represent a significant global health threat to immunocompromised populations, especially individuals with human immunodeficiency virus (HIV). Despite China’s severe HIV burden, molecular epidemiological data on enteric protozoa remain limited in this population. In this study, we investigated the occurrence and molecular characteristics of Cryptosporidium species, Giardia duodenalis, and Enterocytozoon bieneusi among 150 AIDS patients with severe immunodeficiency in Wuhan city, Hubei Province, China. The overall test-positive rate was 5.33% (8/150), comprising Cryptosporidium species (including C. hominis, C. parvum, and C. meleagridis) in 2.00% (3/150) and G. duodenalis (including assemblage A, B, and E) in 3.33% (5/150); E. bieneusi was not detected. Notably, this study reports the first identification of the C. parvum subtype IIcA5G3 in humans in China, certainly indicating possible cross-border transmission. Furthermore, the detection of C. meleagridis IIIbA22G1R1c provided additional molecular evidence for chicken-to-human transmission. The finding of G. duodenalis assemblage E highlights the underrecognized zoonotic spillover risks to immunocompromised populations. These findings emphasize the diversity of infectious reservoirs, and the need for enhanced national molecular surveillance of these neglected zoonotic enteric protozoa, alongside targeted interventions for vulnerable populations. Full article

Intestinal microbial eukaryotic parasites represent a significant public and veterinary health burden, especially in low- and middle-income countries, yet their transmission dynamics at the human–animal–environment interface remain poorly characterized in certain countries. This study investigated the prevalence and genetic diversity of key microbial eukaryotes, including Cryptosporidium spp., Giardia duodenalis, Blastocystis spp., Entamoeba histolytica, and Enterocytozoon bieneusi, in a rural village in Iraq. Samples collected from humans (n = 50), livestock (sheep and goats, n = 50), water (n = 20), and soil (n = 20) were analysed using microscopy and molecular methods (qPCR and nested PCR). Blastocystis spp. (78% animals, 16% humans, 45% soil, 5% water) and Cryptosporidium spp. (26% animals, 12% humans, 5% soil, 15% water) were the most frequently found microeukaryotes using either microscopy and/or molecular detection. Molecular methods identified Cryptosporidium parvum in humans and sheep, hinting at zoonotic transmission potential. Enterocytozoon bieneusi and Giardia were also found. Cryptosporidium ubiquitum and E. bieneusi genotypes BEB6 and COS-I, respectively, were detected exclusively in sheep, suggesting roles as potential reservoirs. Blastocystis ST1 was detected in humans, while ST4 and ST10 occurred in sheep. Notably, molecular detection rates of Blastocystis were much lower than those of microscopy. Entamoeba histolytica was not detected. The detection of the same organisms in humans, animals and the environment suggest zoonotic and environmental transmission pathways, which warrant further investigation using the One Health approach. Full article

Waterborne gastrointestinal infections remain a global health concern, with approximately 1.7 billion diarrhea-related illnesses annually attributable to protozoan parasites. These pathogens are transmitted through contaminated water and exhibit high resistance to chlorination, posing substantial challenges to effective water treatment. This study focused on the most prevalent intestinal parasites in the Los Ríos Region of Chile: Blastocystis sp., Giardia duodenalis, and Entamoeba coli. The objectives were to assess the prevalence of eukaryotic parasites in water samples—covering both drinking and recreational sources—to describe the circulating subtypes of Blastocystis sp. and to identify ecological factors associated with parasite presence. Water samples were analyzed using conventional PCR, next-generation sequencing (NGS) was employed for Blastocystis sp. subtype identification, and the environmental predictors were evaluated using a multivariable logistic regression model. A total of 132 water samples were analyzed, of which 15.2% were positive for Blastocystis sp. and 1.5% for E. coli, while no samples tested positive for G. duodenalis. We identified subtypes ST1–ST4 of Blastocystis sp., along with ST7, ST10, ST14, ST21, and ST23–ST26, the latter being reported for the first time in Chile. Ecological factors significantly associated with Blastocystis sp. presence included higher water temperature and greater rainfall at positive sites. Potable water was associated with significantly lower odds of Blastocystis sp. infection (aOR = 0.04, 95% CI: 0.00–0.87; p = 0.041), while precipitation increased infection odds by 3% per additional millimeter (aOR = 1.03, 95% CI: 1.00–1.06; p = 0.036). Greater distance to the nearest farmhouse was also significantly associated with reduced infection risk, suggesting that proximity to livestock environments may influence Blastocystis sp. transmission. These findings help explain the high prevalence of Blastocystis sp. observed in humans in the Los Ríos Region and highlight the pivotal role of ecological conditions in driving waterborne transmission. To our knowledge, this is the first environmental study in Chile to clearly demonstrate the association between human infection, environmental factors, and the transmission dynamics of Blastocystis sp. Full article

Enterocytozoon bieneusi and Giardia duodenalis are major zoonotic pathogens that often cause diarrhea in immunocompromised humans or animals. Beef cattle are important reservoirs for these two pathogens. Yunnan Province is a major region for beef cattle farming, and its suitable climatic conditions facilitate the transmission of the pathogens. However, research on the prevalence and distribution of E. bieneusi and G. duodenalis in beef cattle in Yunnan remains understudied. This study collected 529 fecal samples from seven beef cattle breeds in four regions in Yunnan Province for an epidemiological survey. Nested PCR combined with sequencing was used to detect E. bieneusi and G. duodenalis, and the sequencing results were analyzed to determine genotypes or assemblage types. Our results demonstrate that the prevalence rates of E. bieneusi and G. duodenalis were 3.0% (16/529) and 3.6% (19/529), respectively. The study identified four genotypes of E. bieneusi, including I (n = 8), J (n = 4), BEB8 (n = 3), and BEB4 (n = 1). Both assemblages E (n = 18) and A (n = 1) were identified among G. duodenalis-positive animals. Phylogenetic analysis revealed that the E. bieneusi genotypes detected in this study belong to Group 2. In conclusion, these findings indicate that although the overall prevalence is relatively low compared to other regions, the presence of zoonotic Group 2 genotypes and assemblage A highlights the potential risk of cross-species transmission. Moreover, the results provide foundational data to support the development of region-specific surveillance and control strategies for bovine giardiasis and microsporidiosis, and emphasize the importance of the One Health approach in managing parasitic infections in livestock populations. Full article

Flagellates of the genus Giardia are intestinal parasites with a broad host range. Several Giardia duodenalis variants (assemblages) recently elevated to species rank—G. duodenalis (assemblage A1), G. intestinalis (A2) and Giardia enterica (B) are human pathogens. Giardia enterica has been reported in some hystricomorph rodents such as wild crested porcupines (Hystrix cristata), but no data were previously available from Brazilian porcupines (Coendou prehensilis) and naked mole rats (Heterocephalus glaber). The aim of this study is to genetically identify the Giardia isolates from these three rodent species, all housed in a zoological institution. Fecal samples were processed using the Bailenger concentration method, and DNA was extracted from the sediments using commercial kits. Partial PCR amplification and sequencing of the glutamate dehydrogenase, beta-giardin, and triose-phosphate isomerase genes revealed that all isolates belonged to G. enterica, showing 99–100% identity with sequences available in GenBank. Prevalences could not be reliably estimated due to small group sizes and the resulting proportions may be biased. To our knowledge, this is the first report identifying Giardia (G. enterica) in C. prehensilis and H. glaber, thus expanding the known host range of this parasite species and reinforcing the importance of surveillance in captive wild hosts. Full article

Giardia duodenalis is a flagellated protozoan pathogen causing parasitic enteric disease outbreaks worldwide. Among detection methods, loop-mediated isothermal amplification (LAMP) has high selectivity and sensitivity, and the detection time is lower than that of conventional molecular methods. In this study, three published Giardia LAMP primer sets were tested and adapted to touchdown LAMP conditions. The measurement time, the volume of reagents, the effect of the denaturation step, different kinds of polymerases, and the presence or absence of betaine on the reaction were tested and evaluated. Based on the results of this study, the 66–60 °C range touchdown LAMP with the use of betaine, 90 °C denaturation step, Bst 2.0 WarmStart^® DNA Polymerase, and the primer set of Momoda et al. were the optimal conditions. We increased the analytical sensitivity of the LAMP reaction to 7.8- and 8-fold higher than the previously published methods for G. duodenalis assemblages A and B, with detection limits of 20 and 19.5 fg/assay, respectively, instead of 156 fg/assay. The detection time was less than 49 min for G. duodenalis assemblage A and less than 35 min for assemblage B, compared to the previously published 60 min. Our optimized LAMP protocol can be directly applied to improve Giardia LAMP tests in routine testing laboratories, could be implemented in standard diagnostic or environmental monitoring workflows, and can be used for the development of Giardia LAMP point-of-care devices or high-throughput systems. Full article

This review article highlights the surveillance of bacterial, viral, and parasitic diseases in donkey populations in China. Key findings highlight significant threats from Equine herpesviruses (EHV-8 and EHV-1), which cause encephalitis, abortion, and respiratory distress. Several parasitic infections including Giardia duodenalis, Cryptosporidium spp., Enterocytozoon bieneusi, and Toxoplasma gondii present important zoonotic concerns across multiple regions of China. Additionally, this review synthesizes current knowledge on donkey microbiota across various body sites and examines their functional significance in health and disease. The complex relationship between the microbiota and host health represents a critical area of research in donkeys. Recent molecular advancements have enhanced our understanding of the diverse microbial ecosystems inhabiting different body sites in donkeys and their profound impact on health outcomes. As single-stomach herbivores, donkeys possess complex microbial communities throughout their digestive tracts that are essential for intestinal homeostasis and nutritional processing. Significant variations in microbiota composition exist across different intestinal segments, with the hindgut displaying greater richness and diversity compared to the foregut. Beyond the digestive system, distinct microbial profiles have been characterized across various body sites including the skin, oral cavity, reproductive tract, and body secretions such as milk. The health implications of donkey microbiota extend to critical areas including nutrition, immune function, and disease susceptibility. Research demonstrates how dietary interventions, environmental stressors, and physiological states significantly alter microbial communities, correlating with changes in inflammatory markers, antioxidant responses, and metabolic functions. Additionally, specific microbial signatures associated with conditions like endometritis and respiratory disease suggest the potential for microbiota-based diagnostics and therapeutics. The identification of antibiotic-resistant strains of Proteus mirabilis and Klebsiella pneumoniae in donkey meat highlights food safety concerns requiring enhanced monitoring systems and standardized safety protocols. These findings provide a foundation for improved donkey healthcare management, including targeted disease surveillance, microbiota-based interventions, and protective measures for those working with donkeys or consuming donkey-derived products. Full article

Parasitic infections pose a significant global health burden, affecting millions of people worldwide. Despite their importance, studies integrating human and animal parasitology to understand transmission pathways are scarce. This study, conducted between August 2022 and April 2023, aimed to investigate the prevalence of parasites in humans and domestic dogs in the Los Rios Region, southern Chile, and explore the risk factors associated with parasitism. A total of 291 human participants provided fecal and blood samples for parasitological and serological analyses, while 92 fecal samples from owned dogs were analyzed. The detection of intestinal parasites employed microscopy and molecular techniques, including next-generation sequencing (NGS). Anti-Toxocara canis and anti-Echinococcus granulosus antibodies in humans were assessed using ELISA. Socioeconomic surveys explored the risk factors associated with parasitism. The results showed a parasite prevalence of 39% in humans and 40% in dogs. Anti-Toxocara canis IgG antibodies were detected in 28.2% of humans. Zoonotic subtypes of Giardia duodenalis and Blastocystis sp. were identified. Thus, the results of our study indicate a high prevalence of intestinal and extraintestinal parasites in the human population of our region. Furthermore, our findings underscore the significant risk of zoonotic transmission of parasites from companion animals. This study contributes to the understanding of parasite transmission dynamics in southern Chile and has implications for public health policy and practice. The results emphasize the importance of considering the connection between human, animal, and environmental health to develop effective control strategies and mitigate the impact of parasitic infections. Full article

Cryptosporidium spp. and Giardia duodenalis are important diarrheal agents in children in developing countries. Little is known about their molecular epidemiology; as such, the objective of this study was to determine the risk factors and genetic diversity of both parasites in diarrheal samples in Mozambique. In this study, two nested PCRs targeting ssurRNA and gp60 genes were used for genetic diversity of Cryptosporidium spp. and b-giardin for G. duodenalis. Sociodemographic and clinical characteristics were obtained through questionnaires. The location (odds ratio [OR] 3.499), mother’s education level (OR 2.150) and age were significant factors for acquiring infection by Cryptosporidium spp. (p < 0.05). Cryptosporidium hominis was the predominant (77.8%) species. Four families (three C. hominis and one C. parvum) were identified, with the highest for Ib (73.9%), followed by Id (13%), Ia (8.7%) and IIc (4.3%). The location (p-value < 0.001), drinking untreated water (p-value = 0.04) and living in masonry houses (p-value = 0.002) were identified as risks associated with G. duodenalis infection. Assemblage A was the dominant type (65.2%). Among the subassemblages of assemblage A, AII was the most frequent (86.6%), followed by AIII (6.6%). For assemblage B, subassemblages BIII (87.5%) and BIV (12.5%) were identified. The dominance of the subtype IbA9G3 of C. hominis, as well as the AII subassemblage of G. duodenalis, seems to indicate that the transmission of both protozoa occurs mainly through the anthroponotic route. Full article

Giardia duodenalis is a zoonotic parasite that causes gastrointestinal diseases in both humans and animals. To evaluate the prevalence and genetic diversity of G. duodenalis in black goats, we collected 539 fecal samples from nine districts in Fujian Province, China. The presence of G. duodenalis was confirmed through nested PCR targeting the SSU rRNA gene, and genotyping was performed at the beta-giardin, glutamate dehydrogenase, and triosephosphate isomerase loci. Among the samples, 115 tested positive, yielding an overall infection rate of 21.34%. Assemblages A and E were identified, with assemblage E being predominant. Statistical analysis revealed significant regional differences in infection rates (p < 0.01), with Zhangzhou exhibiting the highest infection rate (39%) and Fuzhou the lowest (3.13%). No significant differences in infection rates were observed based on age: 24.56% (56/228) for goats <1 year, 14.92% (27/181) for goats 1–2 years, 26.8% (26/97) for goats 2–3 years, and 18.18% (6/33) for goats ≥ 3 years. Similarly, no significant differences were found between sexes: 24.84% (40/161) for males and 19.84% (75/378) for females. Notably, assemblage A, a zoonotic genotype, was detected, indicating a potential risk of cross-species transmission. This study contributes to a deeper understanding of G. duodenalis in black goats and provides critical data for the development of targeted control strategies in Fujian Province. Full article

The grey seal (Halichoerus grypus) is a fish-eating mammal and an apex predator in the Baltic Sea. It serves as the definitive host for several parasite species that utilize fish as intermediate or paratenic hosts. This study aimed to determine the endoparasite fauna of grey seals by-caught in the Latvian commercial coastal fishery and to analyze the impact of parasites on the seals’ nutritional status. A total of 59 grey seals were collected for parasitological analysis. Six parasite species were identified, with all seals infected by Contracaecum sp. and Corynosoma semerme. High prevalence rates were observed for Corynosoma strumosum (69.4%), Parafilaroides gymnurus (44.8%), and Pseudamphistomum truncatum (27.1%). Giardia duodenalis was detected in two animals, marking its first report in the Baltic Sea grey seals. A significant negative correlation was found between the infection intensity of C. semerme (Rs = −0.324, p = 0.013) and the nutritional status of the grey seals. Full article

Cryptosporidium spp. and Giardia duodenalis are zoonotic food- and water-borne protozoa of veterinary importance. They are one of the main causes of diarrhea in domestic dogs (Canis familiaris). Wild canids, such as red foxes (Vulpes vulpes) and raccoon dogs (Nyctereutes procyonoides), can act as natural reservoirs for these parasites. The aim of this study was to estimate the prevalence of these pathogens and analyze possible factors that may affect the infection in wild and domestic canids. A total of 373 domestic dog, 219 red fox, and 78 raccoon dog fecal samples were collected and tested for Cryptosporidium spp. and G. duodenalis presence with direct immunofluorescent staining. The dog owners filled a questionnaire on the dog’s habits and lifestyle to identify and analyze potential factors that may affect the occurrence of these parasites in dogs. Cryptosporidium spp. were found in 16.3%, 28.3%, and 28.2% and G. duodenalis in 0.7%, 27.4%, and 30.8% of the examined dogs, red foxes, and raccoon dogs, respectively. The highest prevalence was observed in puppies—15.4% and 18.5% for Cryptosporidium spp. and G. duodenalis, respectively. In all three canid species, infection with Cryptosporidium increases the risk of co-infection with Giardia and vice versa. Full article

Objective: This study aims to determine the association between anthropometric values and laboratory tests with parasitosis diagnosis and identify diagnostic models for parasitosis without relying on copro-parasitological examinations. Methods: Data were collected from 1894 children aged 0–14 who attended a medical center for low-income children in Lima, Peru, between 2021 and 2022. Anthropometric data (BMI, weight, height), laboratory data (red blood cells, hemoglobin, platelets, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, eosinophils), and parasitological examination results were analyzed. Prevalence ratios for the association between parasitosis and each anthropometric and laboratory variable were estimated using multivariable Poisson regression. Regression models were developed for each type of parasite found, and the diagnostic value was assessed using ROC curves. Results: A high prevalence of parasitosis was identified (41.9%), including Blastocystis hominis (29.1%), Endolimax nana (7.76%), Entamoeba coli (5.97%), Giardia duodenalis (6.44%), and Enterobius vermicularis (1.85%). It was found that the male sex (PRa 1.18), the age group of 2–5 years (PRa 4.83) and >5 years (PRa 4.59), the percentage of eosinophils (PRa 1.02 for every 1% increase), and height/age with −5 SD (PRa 1.34) were associated with a greater risk of parasitosis. Satisfactory values were only shown for diagnostic models associating Enterobius vermicularis and BMI, with a diagnostic value of 70.9% and 70.2% for a BMI < 12 and hematocrit > 29.8%, and BMI < 12 and hemoglobin < 10.6 g/L, respectively. Conclusions: Satisfactory diagnostic value models were only found for parasitosis by Enterobius vermicularis, suggesting the potential for reducing reliance on copro-parasitological exams in resource-limited settings. Full article