Microbial Contamination of Surface Water Sources in Nigeria: A Review

Abstract

The microbiological quality of surface water has become a determining factor in water safety, usability and ecological sustainability. Surface water in most developing countries is frequently contaminated by faecal waste because of the typically poor sanitation practices both in rural and urban areas. This has resulted in water-related illnesses, including cholera, typhoid, polio, diarrhoea, dysentery, gastroenteritis, and wound infections, which are caused by water-borne microorganisms. This study investigated perspectives on microbial pollution of surface water sources in Nigeria. The objectives examined pollution pathways, public health implications, and management strategies. This study utilized the PRISMA 2020 systematic literature review methodology, which helped to provide a comprehensive overview of the current state of research in microbial contamination of surface water sources. A wide-ranging literature search identified 82 records from different electronic databases including Scopus, Research Gate, Google Scholars and Web of Science, the screening of subject title and abstract including the elimination of duplicates and irrelevant records. The outcome clearly revealed that Nigerian surface water resources are grossly contaminated with microorganisms exceeding water quality standards for surface water in most cases. The potential pollution sources and pathways identified included areas with high commercial activities around river catchments and direct exposure to open defecation. There was a high prevalence of microorganisms including Escherichia coli, Shigella spp., Salmonella spp., Klebsiella spp, Proteus spp., Bacillus sp., Staphylococcus spp. and several coliform bacteria including Faecal and total coliforms across the investigated water bodies. Microbial pollution pathways identified in this investigation were linked to indiscriminate waste disposal, runoff from agricultural lands, untreated domestic wastewater, and commercial activities occurring near water bodies. Therefore, developing and implementing efficient strategies to prevent and control microbiological pollution through routine water monitoring plans, improved water safety plans, sanitation, and waste management including real-time monitoring technologies is essential for the reduction of microbial contamination as well as protecting public health in Nigeria.