Document Type : Original Article


1 Department of Biological Science Technology, Federal Polytechnic Mubi, PMB 035 Mubi, Adamawa State, Nigeria

2 Department of Microbiology, Adamawa State University, Mubi, Adamawa State, Nigeria

3 Department of Biomedical and Pharmaceutical Technology, Federal Polytechnic Mubi, Adamawa State, Nigeria


The ability of the bacterial isolate to cause debilitating effects on the host is intricate and is a function of many factors, particularly that of the host and the bacteria. Among the bacterial factors are the virulence mechanisms. As such this research was a cross-sectional study conducted between October–December 2021 to establish the existence of virulence determinants on bacterial isolates from hospital fomites and the hands of healthcare workers. To achieve this, 100 samples (including sink, beddings, door handles, benches, and hands of healthcare workers) from children, female and male wards of Mubi General Hospital were analyzed for bacterial growth and were identified by standard procedure. Isolates were subsequently screened for virulent determinants (hemolysis, hemagglutination, biofilm production, and heteroresistance) phenotypically by standard methods. From the 72 bacterial isolates recovered, 23(31.9%) were biofilm-producing organisms. Of these, 15(20.8%) and 8(11.1%) were moderate and high biofilm-producing organisms respectively with no statistical difference (P=0.665). Pseudomonas aeruginosa (13.9%) was the most predominant biofilm-producing organism. Furthermore, hemolysin production was predominant in Staphylococcus aureus (71.4%), while positive hemagglutination reaction was predominant in P. aeruginosa (38.5%). Sixteen (16) bacterial isolates showed heteroresistance (HR) to various antibiotics; of these, Escherichia coli (43.8%) constitute the majority of the isolates. The expression of such virulence determinants by bacterial isolates in the study area may constitute a health risk to patients and hamper the quality of health care delivery.  

Graphical Abstract

Screening for some virulent factors among bacterial isolates from surfaces of hospital fomites and hands of healthcare workers


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Dr. Musa Yakubu Tula
Federal Polytechnic Mubi
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