The Role of Houseflies, Musca domestica L. (Diptera: Muscidae) as a Mechanical Vector for ESKAPE Pathogens and Drug Resistance

Introduction: The housefly (Musca domestica) is an important host for various pathogenic bacteria, including the ESKAPE group, and acts as a reservoir for transmitting resistance factors. In this regard, this study was performed in order to survey the role of houseflies as a mechanical vector for ESKAPE pathogens and antibiotic resistance profiles of these strains in the four teaching hospitals and rural areas in Babol, north of Iran. In this cross-sectional study, 280 adult house flies were collected with a sterilized nylon net. Methods: All samples were put inside separately in a sterile tube and anesthetized using freezing at 0#146;C for 5 minutes. Bacterial isolates were identified from the external and internal surfaces. The antibiotic susceptibility test was performed by the disk diffusion method. A. baumannii, P. aeruginosa, and Enterobacter isolates were not detected in rural samples. Only one methicillin-resistance S. aureus was found in rural flies. In hospitals, the prevalence of the ESKAPE pathogens in the Cuticular surface and GI were 22.9% and 22.1%, respectively. Results: In total, the highest and lowest frequency rate was related to P. aeruginosa (6.1%) and A. baumannii (1.1%). Also, 66.7%, 5.9%, and 12.5% of A. baumannii, P. aeruginosa, and Enterobacter were resistant to imipenem, respectively. 21.4% of E. faecium were resistant to vancomycin. In total, 63 (22.5%) bacterial species collected from both the cuticular surface and GI, 29 (46%) were multidrug- resistant (MDR). Conclusion: Houseflies obtained from hospitals may be involved in the distribution of drug-resistant bacteria and may increase the potential of human exposure to drug-resistant organisms.