Evaluation of Pattern of Bacterial Contamination of Microbiological Laboratory in Relation to Cleaning and Disinfection Practices in a Super Specialization Hospital in Delhi, India

Background: Microbiological laboratories are critical for diagnostic testing and infectious disease surveillance. However, they are prone to microbial contamination, which can impact diagnostic accuracy and patient safety. This study aimed to evaluate the pattern of bacterial contamination in a microbiological laboratory at a super-specialized hospital in Delhi and to develop effective contamination control strategies. Methods: A cross-sectional study was conducted from August 2022 to December 2022, involving the collection of 4000 surface swab samples from various laboratory areas. Samples were cultured on blood and MacConkey agar, incubated for 24 hours, and bacterial colonies were identified using standard microbiological techniques. Statistical analyses were performed to assess contamination levels and the effectiveness of cleaning protocols. Results: The culture positivity rate was 39%, with 1563 out of 4000 samples detected as positive for bacteria. Of these, 90.47% had multiple isolates, with the most common being aerobic spore-forming bacilli, Staphylococcus aureus, Escherichia coli, and Acinetobacter baumannii. Laboratory workstations and incubators showed the highest contamination. Cleaning significantly reduced bacterial presence, with a p-value < 0.00001. Specific organisms isolated from different areas included ASB, Micrococcus, Coagulase-negative staphylococcus species, Staphylococcus aureus. Conclusion: The study highlights substantial bacterial contamination across laboratory surfaces, underscoring the need for stringent contamination control measures. Key recommendations include routine cleaning and disinfection, staff training on aseptic techniques, environmental monitoring, and strict adherence to sterilization and biosafety protocols. These measures are essential to maintain diagnostic accuracy and safeguard personnel against laboratory-acquired infections.