Background: Babesia and Theileria are potential threats to the livestock industry, causing considerable economic losses. These tick‐borne blood parasites are more prevalent in crossbred cattle than local cattle in Bangladesh.Objectives: To confirm the species of Babesia and Theileria in crossbred cattle from the northern part of Bangladesh using conventional and molecular tools.Methods: A total of 385 crossbred cattle blood samples were subjected to DNA extraction and PCR. For molecular detection, B. bigemina rhoptry‐associated protein 1a, B. bovis spherical body protein‐4, and Theileria spp. 18S rRNA were used as the marker genes.Results: Using PCR, only 72 (18.7%) samples were found piroplasm positive, of which 12.2% Theileria, 4.7% Babesia, and 1.8% mixed infections. Both Babesia (7.3%), Theileria (7.7%) and mixed (2.8%) infections were detected in Sirajganj, and only Theileria (20.4%) was detected in Rangpur district. By PCR and nPCR we detected B. bigemina and T. annulata in Sirajganj district, and Theileria sp. in Rangpur district. The target gene sequences of isolated pathogens confirmed B. bigemina and T. annulata, and Theileria sp from these samples. Blood smears of all samples were also examined microscopically for Babesia and/or Theileria spp. and 14.3% of samples were found positive, of which 5.9% Babesia and 8.3% Theileria. Generally, the pathogens detected in Sirajgang and Rangpur were genetically related to South Asia, particularly South East Asian isolates.Conclusions: These findings provide information for a better understanding of the epidemiology of Babesia and Theileria as well as to improve the approaches for diagnosis and control of tick‐borne diseases in Bangladesh.

Schistosomiasis is a neglected tropical disease (NTD) caused by blood flukes (Schistosoma spp.). Schistosomatids affect a wide array of vertebrate hosts, including humans. In the present study, multiple species of schistosomatids were identified by isolating schistosomatid cercariae (SC) from naturally infected snails. We also described different biotic and abiotic factors influencing SC infections in snails and reported human cercarial dermatitis (HCD) for the first time in Bangladesh. A total of 22,012 snails of seven species: Lymnaea auricularia, L. luteola, Indoplanorbis exustus, Physa acuta, Viviparus bengalensis, Brotia spp., and Thiara spp., were collected and examined. Among these snails, 581 (2.6%) belonging to five species: L. luteola, L. auricularia, P. acuta, I. exustus, and V. bengalensis, were infected with SC. The rate of infection was the highest for L. luteola (11.1%), followed by L. auricularia (5.3%), and was the lowest for V. bengalensis (0.4%). Prevalence in snails was the highest in September (16.8%), followed by October (9.5%) and November (8.8%), and was the lowest in colder months, such as January (1.8%) and February (2.1%). Infections with schistosomatids were more common in larger snails and snails collected from sunny areas. We confirmed the presence of Schistosoma indicum, S. incognitum, S. nasale, S. spindale, and Trichobilharzia szidati by PCR and sequencing. Through a questionnaire survey, we detected HCD in 214 (53.5%) individuals, and the infection rate was almost equally distributed across all professions. Collectively, the present results suggest that lymnaeid snails are the main vector for Schistosoma spp. prevalent in Bangladesh, and schistosomatids with zoonotic potential are also prevalent.

Objectives: The study aimed to detect Neospora caninum by nested PCR (nPCR) in aborted fetuses of cattle, sheep, and goats in Bangladesh. Materials and Methods: The head portion of each aborted fetus (111) was dissected at each sampling site and transferred to the laboratory in an ice box. Data on risk factors associated with N. caninum infection were simultaneously collected. Deoxyribonucleic acid was extracted from brain tissue to perform nPCR targeting the internal transcribed spacer 1 (ITS1) ribosomal DNA (rDNA) gene of N. caninum and sequencing was performed from the representative positive samples. Results: By nPCR, N. caninum was found in 16.0% of aborted fetuses of cattle, followed by sheep (14.81%) and goats (11.78%). The highest prevalence was found in aborted fetuses of animals during the second trimester (27.78%) of pregnancy aged 2 to 4 years (18.75%). Obtained sequences showed they were completely matched with N. caninum ITS1 rDNA gene deposited in GenBank. Univariate analysis demonstrated that pregnancy stages (trimesters), abortion history of the animals, and access to dogs in animal farms were significantly (p ≤ 0.05) correlated with N. caninum infection. Conclusion: This study represents the first investigation into the molecular detection, phylogenetic characterization, and analysis of risk factors associated with N. caninum in livestock in Bangladesh. According to the research findings, N. caninum infection may have a role in abortion cases and the ensuing financial losses in the nation’s livestock industry.

A cross-sectional study was conducted in Bangladesh to determine the prevalence, molecular detection, and risk factors of Eimeria spp. infection in native and exotic chickens under various management systems. A total of 1,500 fecal samples were collected from different breeds, age groups, and sexes across multiple districts. Fecal examination using flotation and McMaster techniques identified positive cases, followed by molecular detection of Eimeria species. A questionnaire survey was also conducted to assess potential risk factors. Among the 1,500 chickens, 87 (5.8%) were positive for Eimeria oocysts, with higher prevalence in exotic breeds (7.96%) than native breeds (4.13%). The prevalence rates were 18.40%, 13.98%, 12.09%, and 3.40% in Aseel, Broiler, Sonali, and Deshi chickens, respectively, with no infection found in Naked Neck, Hilly, or Fayoumi breeds. Molecular analysis detected six Eimeria species: E. tenella was detected in 64 samples (62.07%) and in all breeds with the highest occurrence in Aseel. E. acervulina was the second most common species (25.28%), found in 23 samples from Deshi, Broiler and Sonali breeds. Other species, including E. brunetti, E. mitis, E. necatrix, and E. maxima, were rare and sparsely distributed. Chickens fed commercial feed (7.88%) had significantly higher infection rates (p < 0.0013) than those on local feed (3.99%). Intensive rearing systems (15.27%) showed higher infection rates compared to free-ranging systems, but no infection occurred in intensive systems without litter or semi-intensive systems. This is the first comprehensive report on infection status of Eimeria in chickens including all native breeds rearing in different management system in Bangladesh.

Toxoplasma gondii is a globally significant parasite with no genotyping data available from Bangladesh. This study aimed to determine the genotype distribution and associated risk factors of T. gondii infection in animals in Trishal Upazila, Mymensingh district. From June 2020 to December 2023, a total of 170 samples from cattle, goats, sheep, cats, dogs, chickens, and rodents in the study area and examined using nested PCR targeting the B1 gene of T. gondii . Positive samples were genotyped by multilocus nested PCR-RFLP at ten genetic markers. Risk factor data were analyzed using logistic regression at the farm or owner level. The overall infection rate of 21.76% (37/170), with the highest prevalence observed in cyst samples from slaughtered cattle (42.9%) and cat feces (33.3%). Genotyping revealed a predominance of Type I and mixed genotypes (I/II, I/III) in cattle, cats, dogs, and rodents, while goats and sheep predominantly carried Type II or III. Chickens exhibited a mixed II/III allelic pattern with Type I alleles at the C22-8 locus. The use of pond/river water as a drinking source was a significant risk factor, with animals from these sources showing more than threefold higher odds of infection compared to tube-well users (p = 0.038). Backyard or small-holder farming, improper carcasses/offals/ placenta disposal, lack of rodent control, and unhygienic slaughter practices showed positive but non-significant associations with infection. This first report of T. gondii genotyping in Bangladesh highlights the presence of diverse and potentially virulent genotypes in food-producing animals, posing a notable zoonotic risk.