Assessment of Microbial Air Quality in Selected Classrooms in Nigeria Maritime University, Okerenkoko, Delta State

Abstract

This study assessed the microbial air quality in selected classrooms at Nigeria Maritime University, Okerenkoko campus, Delta State. The aim was to isolate and identify pathogenic microorganisms from the classroom air, determine the antibiotic susceptibility pattern of the bacterial isolates, and compare the results with the indoor air quality standards for non-industrial premises established by the Commission of European Communities. In the Delta State, artisanal activities take place in nearby communities close to the university. In this investigation, four classrooms were utilized, and a freshly manufactured nutrient and potato dextrose agar were exposed for 30, 60, 90, and 120 minutes in order to conduct bacteriological and mycological assessments. The manufacturer’s instructions were followed for measuring and dissolving Sabouraud dextrose agar and standard plate count agar (SPCA) in distilled water. Following the development of visible colonies, the plates were incubated and counted; the colonies were displayed in CFU/m³.  Lecture Hall 4’s microbial quality was found to be 4.6 CFU/m³ after 30 minutes of exposure, 3.51×10² CFU/m³ after 60 minutes, and 1.12×10³ CFU/m² after 120 minutes. The mycological examination found that Lecture Hall 4 had a concentration value of 1.72×10² CFU/m³ for the 30-minute exposure, 1.26×10³ CFU/m³ for the 60-minute exposure, and 1.12×10³ CFU/m³ for the 120-minute exposure. These isolates included Acinetobacter sp., Streptococcus sp., Proteus sp., Serratia sp., Klebsiella sp., and Micrococcus sp. It was shown that the Proteus species with the initials LH5B had a zone of inhibition of 35.79 mm to augmentin and 32.08 mm to levofloxacin. The zone of inhibition between Klebsiella sp. Isolated from lecture hall 6, ofloxacin was found to be 27.76 mm and 30.08 mm, respectively. Gram-negative bacterial isolates showed sensitivity to every antibiotic tested, while gram-positive bacterial isolates showed resistance to pefloxacin and sensitivity to the remaining drugs. Amoxicillin and pefloxacin were the only antibiotics that did not affect the isolate Serratia sp. Educating students and staff on practices that can reduce microbial spread, the university administration must create a strong mechanism to clean and eliminate aerosols from classrooms.