Detection of Carbapenemase Genes in Gram-Negative Bacteria Isolated from the Hospital Environment of Aminu Kano Teaching Hospital

Carbapenem-resistant Gram-negative bacteria (CR-GNB) harboring carbapenemase genes represent a critical infectious disease threat in hospital environments globally. Environmental contamination of healthcare surfaces and equipment serves as a reservoir for CR-GNB transmission to vulnerable patients. This study detected carbapenemase genes in Gram-negative bacteria isolated from the hospital environment of Aminu Kano Teaching Hospital (AKTH), Kano State, Northwest Nigeria. Swab samples were collected from 80 high-touch surfaces including bed rails, door handles, sink drains, and ventilator surfaces across four wards. Bacteria were isolated on MacConkey agar supplemented with meropenem (1 mg/L). Phenotypic carbapenemase screening used the modified carbapenem inactivation method (mCIM) test. PCR was performed for blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP carbapenemase gene families. Carbapenem-resistant isolates were obtained from 37.5% of environmental samples, predominantly Klebsiella pneumoniae and Acinetobacter baumannii. blaNDM-1 was the most prevalent carbapenemase gene (52%), followed by blaOXA-48 (28%). Environmental clustering of blaNDM-carrying K. pneumoniae in the neonatal and surgical ICUs suggests clonal spread. These findings call for urgent infection control interventions and enhanced environmental disinfection protocols at AKTH. Keywords: carbapenemase, blaNDM, hospital environment, Gram-negative bacteria, Kano.