Efficiency of Ultra-Violet (UV) Water Treatment Systems in Packaged Water Production Companies of Ouagadougou (Burkina Faso) and Antibiotic Resistance Profiles of Isolated Bacteria

Among water treatment techniques, UV rays are mainly used to disinfect packaged drinking water. The objective of this study was to evaluate the effectiveness of water disinfection by UV rays in packaged water production companies in the city of Ouagadougou. Fifty-four (54) packaged water samples were taken from 27 companies in the city of Ouagadougou. Detection of different microorganisms was carried out using the membrane filtration method. The identification of the isolated coliforms was made using the API 20E trips. Antibiotic resistance was assessed using the KIRBY BAUER agar diffusion method. using ampicillin, amoxiclllin, cetazidim, ceftriazone, imipenem, meropenem, kanamycin, gentamicin, ciprofloxacin and norfloxacin. The results of microbiological investigations showed the presence of bacteria in some packaged water from certain companies. Of the 27 companies investigated, total coliforms were detected in 20 companies, E. coli in one company, Pseudomonas aeruginosa in one company, and sulfite-reducing anaerobic bacteria in 4 companies. Of the 27 companies, the effectiveness of UV disinfection was observed in only 25.92% with a total absence of coliforms, E. coli, intestinal enterococci, Pseudomonas aeruginosa and sulphite-reducing anaerobic bacteria. Twelve (12) species of coliforms including Enterobacter ssp, Enterobacter cloacae, Enterobacter amnigenus, Serratia liquefaciens, Chryseomonas luteola, Chryseobacterium indologenes, Stenotrophomonas maltophilia, Myroides spp, Pantoea spp, Burkholderia cepacia, Serratia ficaria and Enterobacter sakazakii have been detected. The resistance profile showed that some coliforms were resistant to β-lactams and aminoglycosides. This study shows that the technique of disinfection of water by UV rays is not effective in certain companies in Ouagadougou and could be explained by diverse reasons including UV systems defiances.