Metabarcoding Study of Fecal Bacterial and Eukaryotic Pathogens in Stray and Pet Cats in Seoul, South Korea, 2022

Zoonotic diseases pose substantial public health risks because of their potential transmission from animals to humans. As pets, cats can harbor these pathogens. The objective of this study was to describe bacterial and eukaryotic pathogens in the feces of stray and pet cats in Seoul, South Korea, using next-generation sequencing techniques.

We collected 26 fresh fecal samples (17 from pet cats and 9 from stray cats) in Seoul's Mapo-gu District in April and May 2022. Amplicon sequencing targeted the V4 region of the 16S rRNA gene for bacterial pathogens and the V9 region of the 18S rRNA gene for eukaryotic pathogens. We used QIIME 2 to conduct bioinformatic analysis, assessing alpha diversity with the Shannon Diversity Index and beta diversity with principal coordinates analysis and permutational multivariate analysis of variance. We used ALDEx2 and an analysis of the composition of microbiomes to analyze differential abundance and χ² tests to assess pathogen prevalence.

Across all 26 samples, Helicobacter spp (77%; n = 20) and Campylobacter spp (69%; n = 18) were the most prevalent bacterial pathogens. Escherichia-Shigella spp were more common in stray cats (56% [5 of 9]) than in pet cats (12% [2 of 17]) as were Brachyspira spp (stray cats, 44% [4 of 9]; pet cats, 0%). Of eukaryotic pathogens, Giardia spp (19% [5 of 26]) were most prevalent across both groups, with Pentatrichomonas spp significantly more common in stray cats (22% [2 of 9]) than in pet cats (0%).

This study found distinct fecal microbial communities in stray versus pet cats, with a higher prevalence of potential pathogens in stray cats. These findings emphasize the need for public health planning and effective measures for controlling stray cats.