A better understanding of the epidemiology of helminths in animal hosts is important in order to ensure animal welfare, public health and food safety. The aim of this study was to explore parasitism in common animals in Bangladesh. Perception and understanding of animal owners regarding parasitic diseases management were also assessed. A total of 550 fecal samples were examined from common animals (cattle, goat, pig, chicken, dog, and cat) across three different areas of Bangladesh (Dhaka, Sylhet, and Chattogram) from January 2020 to March 2021. Associated risk factors were assessed through questionnaire surveys among 50 animal owners. Parasitological assessment was done using the combined sedimentation-flotation method, and factors associated with infection were modeled using mixed-effects logistic regression. Helminths including Toxocara sp., Spirometra sp., Capillaria sp., Trichuris sp., opisthorchiid, Ascaris suum, Fasciola sp., Paramphistomum sp., strongyles, hookworms, roundworms, taeniid, and acanthocephalans were detected in the examined animals, and overall prevalence was 59.3% (95% CI = 54.1–62.8). Parasites were found in 61.3% (245/400) of food animals and 54.0% (81/150) of companion animals. Animal owners have a good understanding of parasite infections; however, that knowledge was not being translated into practice. Logistic regression analysis showed that frequency of deworming, animal husbandry practice, contact with untreated animals, and treatment-seeking behaviors were significantly associated with parasitic infection. Several types of zoonotic parasites are widely prevalent in animals of Bangladesh and pose a potential risk to human health. This study highlights the need to diagnose animal parasitic infection and intensified case management to avoid spillovers to animals and humans.

Introduction: Endoparasites in captive wildlife might pose a threat to public health; however, very few studies have been conducted on this issue, and much remains to be learned, especially in limited-resource settings. This study aimed to investigate endoparasites of captive wildlife in Bangladesh. Perception and understanding of veterinarians regarding one health and zoonoses were also assessed. Materials and Methods: A cross-sectional study was conducted from October 2019 to August 2020. A total of 45 fecal samples from 18 different species of wild animals (i.e., 11 species of mammals: herbivores, carnivores, and omnivores, six birds, and a single reptile species) were collected randomly. Parasitological assessments were done by modified formalin ether sedimentation technique and rechecked by Sheather’s sugar floatation technique. Molecular identification of Spirometra spp. was conducted by amplifying the cytochrome c oxidase 1 (cox1) gene. Questionnaire surveys among 15 veterinarians and an in-depth interview (IDI) with a zoo officer were conducted. Results: Helminths (Spirometra sp., Capillaria sp., Ascaridia/Heterakis, opisthorchiid, strongyles, acuariid, hookworms, roundworms, and unidentified nematode larvae) and protozoa (coccidian oocyst) were identified, and the overall prevalence was 48.9% (22/45). The cox1 sequences (341 bp) of the Bangladesh-origin Spirometra species from lion showed 99.3–99.7% similarity to the reference sequences of Spirometra decipiens (GenBank No: KJ599679.1; MT122766). The majority of study participants (86.6%) agreed about the importance of endoparasite control in zoo animals, and 73.3% expressed that the one health concept should be promoted in Bangladesh. Only 6.7% of veterinarians perceived confidence in diagnosing parasitic diseases and preventing antiparasiticidal resistance. Conclusions: In the present survey, we found a considerable prevalence of endoparasites in captive wildlife. For the first time, zoonotically important S. decipiens from lion was molecularly characterized in Bangladesh. Veterinarian training is required to improve parasite control knowledge and practice. This study highlights the need for routine parasitological assessment, promotion of one health, and improvement of the implementation of current parasite control strategies in zoo animals.

To assess the prevalence of intestinal helminth infections and associated risk factors among people living in urban slums in Bangladesh. A cross-sectional study was conducted across three clusters: Dhaka, Sylhet and Chattogram. In total, 360 individuals divided into two groups (school-aged children and adults) provided stool samples and completed a semi-structured questionnaire. Parasitological assessment was performed using the formol-ether concentration technique. Overall, 31.7% (114/360) of participants had helminthiasis, with 13.3% (48/360) having mixed infections. Among the infected participants, school-aged children had a higher rate of infection (41.7%, 75/180) compared with adults (21.7%, 39/180). Ascaris lumbricoides was the predominant parasite, followed by hookworms, Trichuris trichiura, Hymenolepis nana, Enterobius vermicularis and Rhabditis sp. Parasitic infections were significantly associated with type of latrine used, direct exposure to soil, open defaecation, and presence of free-roaming animals. Despite continuous efforts to control helminthiasis, a substantial proportion of the study participants were infected with intestinal helminths. Ignorance of the roles of the environment and animals was influential, and had a negative impact on existing control interventions. An integrated public health and veterinary public health approach is required for sustainable control of intestinal helminthiasis.

Accurate diagnosis by precise identification of causative agents is essential for the effectiveness of any control interventions. Despite high zoonotic potential, available literature on hookworms in Bangladesh is still scarce and nonspecific. The objective of this study was to determine the occurrence of hookworms in public locations across northeastern Bangladesh (Sylhet metropolitan area) using integrated parasitological and molecular assays. A total of 130 samples (80 soil and 50 environmental canine feces) were collected and examined using modified flotation technique and formalin-ether sedimentation methods. Modified plate culture was used to isolate larvae. The identification was made based on morphometric features and confirmed by amplifying the ITS region of the nuclear rDNA. Overall, 66.2% (86/130) of examined samples were positive for hookworms infection. Characteristic eggs (61–68 × 29–37 μm) and/or larvae of hookworms were observed in 73.8% (59/80) soils and 54.0% (27/50) environmental fecal samples. Rhabditiform larvae (0.48–0.54 × 0.04–0.07 mm) were observed in cultured samples. Genetic analysis of rDNA sequences revealed the presence of Ancylostoma caninum and Ancylostoma ceylanicum. In this study, hookworms' contamination of the public environment was substantial. To the best of our knowledge, this is the first molecular proof of A. caninum and A. ceylanicum observed in urban public environment in Bangladesh.

The genus Haemonchus is the major abomasal parasite of ruminants responsible for substantial economic losses in tropical and temperate regions. This study was conducted to clarify the morphometry and molecular characterisation of Haemonchus species isolated from sheep in Babati district, Tanzania. A total of 486 trichostrongylid nematodes were recovered from five sheep. Of the total worms, 106 nematodes were distinguished by 37 males and 69 females. The asymmetrical length of dorsal ray and the distance of bulb at the apex of spicules were used for identification of males. In females, the linguiform vulvar flap was the most predominant with 33 out of 69 (48) compared with knobbed morph type which was 25/69 (36) and smooth morph type with 11/69 (16). Partial cox1 sequence fragments of Haemonchus contortus isolates showed 98.8, 99.3, 99.7, 99.5, 99.3, and 98.4 in male, smooth, knobbed, linguiform A, linguiform B, and linguiform C, respectively; with the average nucleotide divergence ranged from 1.03 to 2.35. The amplified fragments of ITS-2 genes in knobbed, linguiform A, and smooth morphotypes revealed 99.4, 98.5, and 98.3, respectively. Phylogenetic analysis was evaluated by employing Bayesian inference and maximum-likelihood, and the tree was distinctly separated into three clusters focusing on H. contortus in cluster I within the family Haemonchidae. Genetic drifting, mutation, and modification of the morphological features of the Haemonchus species described to have an impact on the development of drug resistance. Species identification is necessary to understand which species infect animal host. We recommend more studies on the parasites intensity and the strategies for controlling Haemonchus species in Tanzania.