An Antibiotic susceptibility pattern of bacteria isolated from water storage tanks within Ahmadu Bello University Main Campus, Zaria.

Antibiotic susceptibility pattern of bacteria isolated from water storage tanks within Ahmadu Bello University Main Campus, Zaria.

Abstract

Abstract

Background: Water shortage has been a problem in developing countries due to the scarcity of water. To curtail this problem, water storage tanks were introduced. These water storage tanks, when not properly maintained, serve as a source of contaminants, resulting in global health issues.

AIMS: To evaluate the bacterial contamination and antibiotic susceptibility pattern of the bacterial isolates from water storage tanks in Ahmadu Bello University, Zaria main campus.

Methods:

Forty (40) water storage tanks located at eight different hostels were sampled with sterile swab sticks. The spread plate technique was used to enumerate the microbial distribution. Isolates were cultured and identified using standard Microbiology procedures, which included Gram staining, Growth on selective media, and simple biochemical tests. Antibiotic susceptibility testing was determined using modified Kirby-Bauer disc diffusion and broth microdilution. Biofilm formation was evaluated using Congo red agar-based methods.

Results;

The total heterotrophic bacterial count ranged between 4.6 x10³ to 1.6 x10⁶ CFU/ml, total coliform count ranged between 0.00 ×10³ to 3.0×10⁵ CFU/ml. The eight bacterial isolates from water samples belonged to Escherichia coli, Salmonella sp, Bacillus sp, Staphylococcus spp, Pseudomonas spp, Klebsiella spp, Enterobacter sp, Proteus sp and frequency of occurrences were 20%, 16%, 13%, 10%, 9%, 8%, 13% and 8% respectively.   

The antibiogram showed that gentamicin was the most effective antibiotic, while many showed resistance to tetracycline, vancomycin, nalidixic acid, amoxicillin, and cefoxitin.

The biofilm assay revealed that 50% of the isolates were strong, and 25% moderate.

Conclusion: The presence of this species in the water source has been known to cause diverse diseases in human beings, such as skin infections, wound infections, urinary tract infections, gastroenteritis, and respiratory tract infections, therefore, there is a need for regular washing of water tanks used for water storage.

Key words: Water tanks, bacterial pollution, antibiogram, school hostels