Occurrence of human pathogenic bacteria and their antibiotic resistance in the gut of wild and captive sloth bears

Abstract

A growing worldwide problem of antibiotic resistance (AR) has significant effects on both human and animal health. The present study compared the presence of human pathogens in wild and captive sloth bear populations, and their resistance to antibiotics. The study was conducted using a non-invasive method, by isolating microorganisms from fresh scat samples collected from the Jessore Wildlife Sanctuary of Gujarat (wild), and the Bannerghatta Bear Rescue Centre and Bannerghatta Zoo (captive). The isolates were identified and their resistance to different antibiotics were studied using the VITEK2 system. We found that captive sloth bears exhibit significantly higher levels of potential human pathogens and resistance to antibiotics compared to their wild counterparts. Further, the antimicrobial susceptibility test revealed that ten out of 22 organisms from captive population are resistant to 38 different antibiotics, whereas, in the case of wild populations, only two out of 19 organisms were found to be resistant to 34 different antibiotics. Captive sloth bears, fed on human-associated food and living in closer proximity to humans, presented a distinct microbial community with greater anthropogenic influence compared to the wild bears, which rely on natural diets of social insects, honey, and seasonal fruits. The findings underscore the critical role of AR as a marker of anthropogenic input into wilderness ecosystems and its potential impacts on wildlife conservation and public health. This is the first known study to examine AR in sloth bears, offering novel insights into the transmission dynamics of pathogens between humans and wildlife. Our finding of AR in the sloth bear population is reassuring, though further studies in this area would be helpful.