Identification of Carbapenem Resistance Genes in Escherichia coli Isolated from Blattella germanica by Dot Blot Assay in Hamadan Hospitals, Iran – 2018

Background and Objective: Today, one of the problems of health systems is the presence of cockroaches in hospitals as insects that move freely in and out of the hospitals and are infected with pathogenic bacteria. The aim of this study was to identify carbapenem resistance genes in Escherichia coli isolated from Blattella germanica by dot blot assay in Hamadan hospitals in the west of Iran. Methods: A total of 109 B. germanica from April to September 2018 were collected from ICUs of different hospitals in the Hamadan province, located in western Iran. The B. germanica were identified using reliable taxonomic keys by an expert in the Department of Entomology, insectarium Hamadan University of Medical Sciences, Iran. The antimicrobial susceptibility test was determined by disk diffusion. The dot blot assay was used to identify resistance genes in E. coli isolated from B. germanica. Results: Out of 109 B. germanica samples collected from ICUs of different hospitals in Hamadan, 31 samples (28.44%) were positive for E. coli. The highest frequency of antibiotic resistance against ampicillin (100%) and the lowest resistance to imipenem was observed in two isolates (6.45%). The frequency of genes among E. coli isolates in B. germanica was as follows: bla NDM (4 isolates: 3.66%), bla OXA-48 (one isolate: 0.92%), and other studied genes were not observed in any of the strains. Conclusion: Cockroaches are an important factor in transmitting Enterobacterales and multidrug-resistant (MDR) strains. Therefore, effective preventive and control measures are needed to reduce vector-borne diseases.