Bacteriological Assessment of Indoor Air in Some Selected Units within a Senior High School in Cape Coast, Ghana

Abstract

Indoor air quality (IAQ) is a critical determinant of health, particularly in educational settings where high occupancy and prolonged exposure may increase the risk of microbial contamination. This study assessed the bacteriological composition of indoor air within a Senior High School (SHS) in Cape Coast by enumerating, isolating, and identifying bacterial genera across six key units in the Senior High School. Using a descriptive cross- sectional analysis, air samples were collected using the sedimentation (open-dish) method from the dining hall, library, female dormitory, male dormitory, staff common room, and headmaster’s office. The findings revealed significant variations in bacterial loads, with the dining hall recording the highest concentration at 178.10 CFU/m³, followed by the library (141.59 CFU/m³), female dormitory (123.14 CFU/m³), male dormitory (91.09 CFU/m³), staff common room (68.16 CFU/m³), and head office (46.51 CFU/m³). Analysis of the bacterial genera indicated that Staphylococcus sp. was predominant (39%), followed by Corynebacterium sp. (28%), Pseudomonas sp. (25%), Bacillus sp. (7%), and Neisseria sp. (1%). Statistical analysis revealed significant correlations between microbial abundance and environmental factors such as occupancy, ventilation, and indoor activities, highlighting their role in bacterial dissemination. These results underscore the potential health risks of high microbial loads, including respiratory infections and allergies, and suggest improved ventilation, regulated occupancy, and routine monitoring. The study’s findings provide essential baseline data to inform targeted interventions to enhance IAQ in senior high schools, ultimately contributing to broader public health efforts to minimize airborne microbial hazards in densely populated indoor environments.