Diversity of Biofilm Producing Bacteria in a Drinking Water Distribution System in a Suburban Community in South South Nigeria

Reports of biofilms and associated bacterial communities in drinking water distribution systems (DWDS) have been made from various parts of the world, often in association with several negative implications. Such awareness data is not widespread in Nigeria. Knowledge of this would be essential in improving the quality of drinking water. This study thus set out to explore bacterial diversity in a DWDS and determine the biofilm-forming potential of the bacterial isolates. Standard plating and biochemical test methods were used to isolate and identify bacteria present in a DWDS, and biofilmforming potential of the bacteria determined using the Congo Red Agar (CRA) method. Nine different potentially pathogenic bacterial species were detected, with Staphylococcus aureus and Serratia sp being predominant. A higher number of species was however associated with water samples than swab samples. Using the CRA method, 24.3% of the bacteria were found to be possible biofilm producers, with Klebsiella sp as the predominant organism. The presence of potentially pathogenic bacterial species in this DWDS is considered an early warning signal of public health concern. The biofilmforming ability of some of the isolates further highlights the public health risk considering the association between biofilm formation and increased virulence, pathogenicity and drug resistance of microbes with such potential.