An in-depth study on survival mechanism of bacterial isolates in disinfectants within the hospital environment

Disinfectant resistance poses a significant threat to healthcare facilities, and a study was conducted to understand how bacteria adapt to survive exposure to disinfectants in a tertiary care hospital in Varanasi, India. Four isolates were obtained from chlorhexidine-based handwash and tested against six disinfectants to determine their minimum inhibitory concentration (MIC) and bactericidal concentration (MBC). The study found that the isolates had the highest MBC/MIC ratio against glutaraldehyde, and exposure to a supra-inhibitory concentration of BAC led to a doubling of MIC/MBC. The majority of the isolates were multidrug resistant and strong biofilm producers. The study also identified multiple AMR genes, including blaDIM-1, disinfectant-resistant gene, and efflux pump genes.