Cockroaches (Periplaneta americana) as possible reservoirs of extended spectrum beta-lactamase (ESBL)-producing pathogenic bacteria

Abstract

Cockroaches are excellent vectors of microbes since they carry pathogenic microorganisms and transmit same onto sterile surfaces, food, cloths/beddings and equipment/instruments in the hospital and non-hospital environments. Extended spectrum beta-lactamases (ESBLs) are beta-lactamases capable of hydrolyzing many beta-lactam antibiotics including third-generation cephalosporins; and bacteria that produce them occur in both the community and hospital settings. In this study, a total of 517 adult cockroaches comprising 137 cockroaches from hospital environment and 380 cockroaches from residential homes were bacteriologically analyzed for the isolation and identification of pathogenic bacteria expressing ESBLs. Antibiogram was carried out using the Kirby-Bauer disk diffusion method and ESBL production was detected in the isolated bacteria using the double disk synergy test (DDST) method. A total of 101 isolates of Escherichia coli, 25 isolates of Salmonella species and 5 isolates of Shigella species was recovered from the cockroaches emanating from both the hospital and residential homes. The antibiogram result showed that the isolated E. coli isolates, Salmonella species and Shigella species showed varied levels of multidrug resistance to the tested antibiotics especially to the 3^rd generation cephalosporins such as ceftazidime, cefoxitin, cefotaxime and ceftriaxone. ESBL expression was detected in 16 isolates of E. coli and 4 isolates of Salmonella species. None of the isolated Shigella species expressed ESBL. Cockroaches may play an important role in the spread of multidrug resistant bacteria pathogens within the hospital and non-hospital environments. Thus, it is important to take cockroaches infestations seriously and be on the lookout for bacteria that harbour drug resistant genes such as those that spur ESBL production.