Joy Chinazaekpere MBA

Airborne bacterial contamination in student residential areas poses significant public health risks, particularly in densely populated university settings. This study evaluated the microbial quality of air in two student hostels, Ekosodin and Osasogie, at the University of Benin, Edo State, Nigeria, over a three-week period. Air samples were collected and analyzed for total bacterial counts, cultural and biochemical characteristics, distribution patterns, frequency of occurrence, and antibiotic susceptibility profiles. The results revealed that Ekosodin generally exhibited higher bacterial loads, peaking at 5.4 ± 0.35 ×10³ CFU/m³ during Week 2, whereas Osasogie recorded the lowest load of 2.1 ± 0.20 ×10³ CFU/m³ in Week 3. Six bacterial species were isolated: Staphylococcus aureus, Escherichia coli, Klebsiella sp., Proteus sp., Pseudomonas aeruginosa and Bacillus sp. E. coli (25%) and S. aureus (20%) were the most frequently occurring isolates. Antibiotic susceptibility testing revealed that fluoroquinolones (ciprofloxacin and pefloxacin) and aminoglycosides (gentamicin and streptomycin) were the most effective against the isolates, while beta-lactams (ampicillin and amoxicillin) and cotrimoxazole showed widespread resistance. The Multiple Antibiotic Resistance (MAR) indices ranged from 0.00 (Bacillus sp.) to 0.40 (Pseudomonas aeruginosa), highlighting the presence of multidrugresistant bacteria in the residential air. These findings underscore the need for improved ventilation, hygiene, and routine microbial monitoring in student residential facilities to mitigate the risks of airborne bacterial infections.