Surface and Air Sampling of Key Areas of the Hospital in a Tertiary Care Hospital in Bihar

Background: Operation theatres (OT) and intensive care units (ICU) are considered vulnerable areas for the evolution and spread of healthcare-associated infections (HAI) as well as microbial resistance.The confined environment present in the OTs and ICU facilitates aerosol formation and further builds up infection levels.Surveillance, one of the integral parts of an effective infection control programme, aids in reducing the burden of health care-associated infections and antimicrobial resistance.Methods: This prospective observational study was conducted from September 2022 to February 2024 in the Microbiology laboratory at Katihar Medical College, Katihar.An estimated 768 pre-fumigation surface samples 178 settle plates and the same number of post-fumigation samples were taken from various OTs and ICUs during the entire study period.Results: In total 1892 samples (including surface swabs and settle plates) were processed within 18 months.Growth was detected in 17.8% (137/768) of pre-fumigation swabs and 4.2% (32/768) of post-fumigation swabs.ICU II was found to be most contaminated with 36/137 (26.3%) isolates.Gynae OT was found to be the least contaminated with 3/137(2.1%)isolates.The most common isolate in pre-fumigation surface sample was S. aureus 38/137 (27.7%).The pre-fumigation air bio-load of all OTs and ICUs ranged between 6.16 to 23.28 colonies/90 mm diameter plate/hr.The post-fumigation air bio-load in all OTs and ICUs ranged between 3.00-10.21colonies/90mm diameter plate/hr.Conclusion: There was a significant reduction in the growth in surface samples following fumigation.The mean air bio-load of all OTs and ICUs during pre-fumigation and post-fumigation was within normal limits as per the IMA index.