Pathogenic Bacteria Variation in Hydroelectric Reservoirs: Case of Kossou, Taabo and Faé in Côte D'ivoire

Recent studies have shown that the Taabo, Kossou, and Faé reservoirs are contaminated by faecal pollutants, which could pose health risks to users due to a potentially high abundance of pathogenic bacteria. Accordingly, a monitoring study was planned to assess variation in pathogen abundance, including Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus), in these reservoirs. Water sampling was conducted between February and October of the same year along a linear transect in each reservoir. Pathogenic bacteria were analyzed using culture and polymerase chain reaction (PCR) methods. The primer pairs PA-SS-F/PA-SS-R were used for P. aeruginosa, and 16S rRNA-F/16S rRNA-R were used for S. aureus. Overall, the median concentrations of P. aeruginosa and S. aureus ranged from 0.97 and 2.57 Log CFU/100 mL. The highest concentrations of these bacteria were generally recorded during the rainy periods in June, July, September, and October. Spatially, the highest concentrations were found in the shore areas of the different reservoirs. The results indicated weak correlations between the concentrations of these pathogenic bacteria. To preserve the integrity of these hydroelectric reservoirs, it is advisable to establish safety zones around them and to treat wastewater prior to discharge.