Semi-domesticated dogs as a potential reservoir for zoonotic hookworms in Bangkok, Thailand

Background and Aim: Hookworms are parasitic nematodes that live in the small intestine of their mammalian hosts including humans, dogs, and cats. This study was conducted to determine the prevalence and perform genetic characterization of hookworms using molecular techniques and to elucidate the risk factors associated with hookworm infections among semi-domesticated dogs residing in temples in the Bangkok Metropolitan Area, Thailand. Materials and Methods: A total of 500 fecal samples were collected from semi-domesticated dogs from 91 temples in 48 districts of Bangkok. DNA was extracted and screened using internal transcribed spacer polymerase chain reaction-restriction fragment length polymorphism. In addition, samples positive for Ancylostoma ceylanicum were further characterized at the haplotype level based on the analysis of the mitochondrial cytochrome oxidase-1 gene (cox1). Results: The prevalence of hookworm infections in semi-domesticated dogs was 6.2% (31/500). Hookworm infections were detected in temple-community dogs in 12 of 48 districts (25.0%), with Bang Khen and Lak Si districts having the highest proportion of infected dogs (22.6%). Regarding molecular characterization of hookworm species, 21 positive samples (67.74%) were infected with A. ceylanicum and 10 (32.26%) with Ancylostoma caninum. Characterization of cox1 in A. ceylanicum isolates revealed the presence of a mixture of human and dog isolates. Conclusion: Semi-domesticated dogs act as a potential source of hookworm infections for human and animal populations in Bangkok, Thailand.