Abstract

Background:
Public transportation systems are essential components of urban and semi-urban environments, providing daily affordable and efficient mobility to millions of people daily.

Aim:
This study aimed to examine microorganisms in Wukari’s public transport system, specifically buses and Sienna vehicles.

Methods:
A total of 18 samples were collected from high-contact surfaces (seats, handrails, and door handles) of each vehicle using sterile cotton swabs moistened with normal saline aseptically. These samples were analysed for microbial presence of public health implications at different times of the day. The total bacterial and fungal counts were determined, and bacterial isolates were characterized using colonial morphology, Gram staining, and biochemical tests, such as the catalase, oxidase, indole, citrate, and triple sugar iron tests, while the fungi were characterized using lactophenol cotton blue stain.

Results:
The results showed that the total viable bacterial count was high, especially in the evening. In the morning, bacterial counts ranged from 1.4 × 10⁷ cfu/m³ to 5.4 × 10⁷ cfu/m³, with the highest levels recorded on bus handrails. The bacterial isolates include Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa, Bacillus spp., Acinetobacter baumannii, and Enterobacter aerogenes. Proteus mirabilis (64.8%) was the most prevalent species across all surfaces. Bacillus spp., Pseudomonas aeruginosa, and Escherichia coli were more commonly found in morning samples but were absent in the evening. The spore-forming unit ranged from 0.1 x 107 to 1.0 x 107 sfu/m³. Fungal contamination was observed only in the evening, with Penicillium spp. (50%) and Aspergillus flavus (50%). Both fungi were found exclusively in the buses.

Conclusion:
Public transport vehicles can harbor harmful microorganisms, highlighting the importance of regular cleaning and disinfection.

Key words: Bacteria; Fungi; Microbial contamination; Microorganisms; Public health.