Antimicrobial resistance including extended spectrum beta lactamases (ESBL) and carbapenemase in feacal <em>E. coli</em> isolates from bats

Abstract

Antimicrobial resistance (AMR) is one of the major causes of rising human mortality in hospitals. Although mitigation of AMR is challenging, one health approach has shown success. Bats, a key component in the ecosystem, contribute to about 20% of the world’s entire mammalian population with > 1200 species. Bats found both in rural and urban environments coexisting with the human population play a significant role in agriculture. Although AMR with significant importance has been reported in bats in some countries, a dearth of literature including dissemination of phenotypic antimicrobial resistance in bats Sri Lanka. Therefore, this study was undertaken to analyse the phenotypic antimicrobial resistance of E. coli isolated from bats in the Kandy suburbs in Sri Lanka in June – December 2022 when the worst economic crisis prevailed in the country. The fresh faecal samples were collected from three identified sites in Kandy suburbs. Faecal samples were cultured in MacConkey agar, sub-cultured in blood agar and the identification of E. coli was carried out by conventional methods. A total of 251 E. coli isolates were screened for antimicrobial susceptibility testing by the disk diffusion test. Cefotaxime and meropenem disks were used to determine ESBL and carbapenem resistance respectively. Resistance to carbapenem was observed in E. coli at 8.9%, 7.5% and 7.3% and to extended spectrum beta lactamases (ESBL) at 26.9%, 38.9% and 39.8% in the three sites where samples were collected. Over 50% of frequency was observed for trimethoprim, ampicillin and sulfa trimethoprim combination. The CTX-M was found and NDM-1 was not found by PCR similar to the finding reported previously. Surveillance of AMR in multiple sectors for baseline information on each species in the ecosystem is vital for the interpretation of resistant frequencies. However, the role of bats in the dissemination of AMR determinants needs to be further investigated.