Surveillance of zoonotic Brugia pahangi in monastery cats, Samphran district, Nakhon Pathom, Thailand

Abstract

The mosquito-borne filarial nematode parasites Brugia pahangi and B. malayi have been proposed as potential zoonotic pathogens, with dogs and cats being the main reservoir hosts. The monasteries where both stray and semi-domesticated animals live often serve as areas where humans are exposed to these reservoirs. In Thailand, the prevalence of B. pahangi, particularly in infected monastery cats, is underreported. In this study, we investigated B. pahangi prevalence in cats at 24 temples in the Samphran district, Nakhon Pathom province, central Thailand. In total, 196 blood samples were collected from the cats and examined using the hematocrit capillary tube technique. Then, modified Wright–Giemsa staining was used to morphologically identify microfilaria at the genus level. We then used the polymerase chain reaction (PCR) to target the mitochondrial cytochrome oxidase I (COI) gene and perform sequencing to confirm the species level of the filarial nematode parasite. The results were highly similar to B. pahangi COI (100%). A phylogenetic analysis was then conducted using MEGA X software. The B. pahangi infection prevalence at the study sites was 4.08% (8/196). Most infected cats exhibited no clinical signs and gender and monastery location were non-risk factors for infection. Our study indicated that molecular techniques and phylogenetic analyses are useful tools for identifying filarial parasites and understanding their evolution. Importantly, going forward, our findings will help improve the diagnosis, treatment, control and prevention of zoonotic filarial nematode parasite infections.