Multi-Drug Resistant (MDR) Bacterial Isolates on Close Contact Surfaces and Health Care Workers in Intensive Care Units of a Tertiary Hospital in Bulawayo, Zimbabwe

Abstract

Aims: A cross sectional study was conducted to determine the degree of microbial contamination of environmental surfaces and health-care workers (HCWs) in two multi-bed ICUs at a tertiary-referral hospital in Bulawayo, Zimbabwe. Place and Duration of Study: Mpilo Hospital, National University of Science and Technology Microbiology Department; between January 2017 and August 2017. Methodology: In total 64 surfaces were swabbed in two ICUs; inclusive of 6 hand swabs obtained from on-duty nurses. Fungal and bacterial isolates were identified using standard microbiological methods. Bacterial antibiogram profiles were determined by the Kirby-Bauer disc diffusion method. PCR was used to determine the presence of Extended Spectrum Beta Lactamase (ESBL) genes in isolated Enterobacteriaceae and the presence of the mecA gene in Staphylococcus aureus isolates. Results: Out of the 58 fomites and medical devices swabbed 50 (86.21%) were positive for bacterial contamination, with coagulase negative Staphylococci (CoNS) (20.31%) and Klebsiella species (20.31%) being the most prevalent environmental isolates. All 6 (100%) hand swabs obtained from the HCWs were positive for microbial contamination.  A total of 51 (75%) of the 68 bacterial isolates were resistant to at least 3 antibiotics and 39 multi-drug resistance patterns were exhibited by the MDR isolates. Combinations of the ESBL genes blaCTX-M, blaTEM and blaSHV were detected in Escherichia coli, Klebsiella spp and Pseudomonas aeruginosa isolates.  Methicillin-resistant Staphylococcus isolates (MRSA) were detected using phenotypic and molecular methods. Conclusion: ICU inanimate surfaces and medical equipment in the adult and paediatric ICUs of the referral hospital were heavily contaminated with MDR bacteria that could predispose critically ill patients to acquire nosocomial infections.