Agwaranze Dawn Ify, Usman Ikrimah Mohammed, Nwaneri Chioma Blessing
Journal of Microbiology and Infectious Diseases - 2025;15(4):154-165
Background: Indoor air quality (IAQ) has a significant impact on health, especially in educational settings with high human occupancy. Aim: This study assessed the bacterial load and diversity in the indoor air of classrooms at the Federal University Wukari, Nigeria. Methods: Passive air sampling (settle plate method) was used to collect air samples during morning and evening sessions with 10- and 30minute exposure times. Results: Bacterial loads ranged from 1.5 x 10² to 9.0 x 10² CFU/plate in the morning and from 1.0 x 10² CFU/plate to too numerous to count in the evening. Four bacterial species were identified: Staphylococcus aureus (36.3%), Bacillus subtilis (27.3%), Enterobacter aerogenes (18.2%), and Escherichia coli (18.2%). Staphylococcus aureus was consistently present, whereas E. coli appeared only in the morning samples. Conclusion: The presence of opportunistic pathogens, particularly E. coli , highlights a potential public health risk related to poor ventilation and hygiene. Enhanced IAQ management is recommended to reduce microbial exposure in university classrooms.
