Microbial Safety of Household Drinking Water Used During Weaning of Children Aged 6-24 Months in Lusaka District, Zambia.

Abstract

Background: It is estimated that almost 900 million people lack access to improved drinking water worldwide, and over 5 million of those people live in Zambia. Humans can acquire E. coli and salmonella infections through the consumption of contaminated drinking water. The aim of the study was to investigate the safety of household drinking water provided to children during the weaning period in Lusaka District. Methods: We examined the Salmonella spp. and E. coli levels of contamination in water through a cross-sectional survey conducted over a period of nine months, in 19 townships of Lusaka District. The samples were labelled and transported on ice to the laboratory for analysis, that included bacterial isolation and total bacteria count. Antibiotic susceptibility of the isolated Salmonella spp. and E. coli was also determined. Results: The contaminated water sources with total coliforms amounted to 262 (33.6%). Salmonella spp. (150 positive samples 57.2%) contaminated more water tap samples than did Escherichia coli (23 positive samples 8.7%). The two bacteria showed varying resistance to the selected antibiotics, with the highest being recorded in metronidazole 130 (95.6%) for Salmonella spp. and 53 (89.8%) for Escherichia coli, oxacillin 130 (95.6%) for Salmonella spp. and 57 (96.6%) for Escherichia coli. Conclusion: Considerable and extensive contamination of Salmonella spp. and E. coli in water in households in the Lusaka district has been revealed. Isolated Salmonella spp. and E. coli isolates unveiled resistance to multiple antimicrobial drugs: mainly to metronidazole, and oxacillin. These results raise serious concerns regarding the safety of drinking water in Lusaka, as well as regarding the prospects for antibiotic treatment of enteric infections in Lusaka