Prevalence of Antibiotic-Resistant Bacteria in Domestic Water Storage Tanks in Sidon, Lebanon

Abstract

Safe, accessible, and good water quality are essential characteristics for reducing various waterborne diseases. Since domestic water is the water most consumed by Lebanese people, cleaning household water tanks is important to prevent their exposure to pathogenic microorganisms. Generally, all the stages of the value chain of the Lebanese water sector are still imperfect. Thus, the domestic water should be regularly tested, especially in the impoverished landmarks where water quality is the worst. The aim of this study is to evaluate the physicochemical parameters and microbiological quality of the water in the storage tanks of homes in Sidon, Lebanon. Fifty water samples were collected aseptically from domestic water storage tanks. The microbiological assessment was performed using basic plating techniques. Identification of isolated bacteria was performed using MALDI-TOF-MS. Physicochemical parameters were assessed using titration, pH, and conductivity measurements. Antibiotic-susceptibility testing was performed using antibiotic disks. Screening for virulence genes in bacteria was carried out via polymerase chain reaction (PCR). Most of the physicochemical parameters were within the permissible limits of the World Health Organization (WHO) for drinking water. The heterotrophic plate count (HPC) varied between the water samples. The total coliform, fecal coliform, and Escherichia coli (E. coli) contaminate was 54%, 20%, and 16% in each of the samples, respectively. Other bacteria isolated from household water included intestinal Enterococcus faecalis (E. faecalis) (68%), Staphylococcus aureus (S. aureus) (68%), and Pseudomonas aeruginosa (P. aeruginosa) (22%). Other predominant isolates recovered from the samples were also identified. The bacterial isolates showed a prevalence of resistance and intermediate resistance against the tested antibiotic agents. Multi-resistant Staphylococcus aureus (MRSA) was detected in 21% of the collected S. aureus, using cefoxitin agent and mecA gene detection. A prevalence of virulence genes in both P. aeruginosa and S. aureus was also noticed. Our data show that Sidon domestic water is not suitable for either drinking or home applications.