Biofilm formation of methicillin resistant Staphylococcus aureus on hospital environmental surfaces as potential sources of infection among hospitalized patients

Background: Antibiotic resistance and biofilm production have become a significant and growing threat to public and environmental health. The occurrence of methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin Resistant Staphylococcus aureus (VRSA) in Nigeria is well documented in clinical samples. However, findings on MRSA and VRSA from hospital environmental surfaces (HES) are yet to be adequately reported. The current study determined the prevalence of MRSA and VRSA in some HES and their ability to form biofilms. Methods: A total of 60 samples obtained from some HES which included walls, door handles, toilet seats, floors, bed rails and bedside tables were assessed for Staphylococcus aureus using Blood agar and mannitol salt agar (MSA) by a standard culture-based approach. Methicillin and vancomycin susceptibility profile of the Staphylococcus aureus isolates were determined using the disc diffusion method. Biofilm production was determined using Congo red agar (CRA) assay. Results: Of the 60 samples tested, 42 (70.0%) Staphylococcus aureus were isolated, with a majority recovered from walls, bed rails and bedside tables. Among the Staphylococcus aureus isolates, 90.5% (38/42) were MRSA and all the MRSA isolates were resistant to vancomycin. Biofilm profile revealed 20 (52.6%) strong biofilm formers and 2 (5.3%) moderate biofilm formers. Conclusion: The high prevalence of MRSA, VRSA and strong biofilm forming capacity of isolates from HES is a threat to environmental health and risk of disease development in hospitalized patients.