Quantitative exposure assessment to vibrio cholerae through consumption of fresh fish in Lusaka province, Zambia.

Fresh fish is one of the cheapest sources of proteins in the Zambian diet and widely consumed nationwide. Fresh fish harbours a number of spoilage bacteria and pathogens including V. cholerae which cause cholera in humans. Consumption of contaminated fresh fish has been linked to zoonotic transmission of diseases in humans. The aim of the study was to carry out a quantitative exposure assessment to Vibrio cholerae through consumption of fresh fish in Lusaka Province of Zambia. The data used to achieve this objective were obtained from reviews of scientific literature, government reports, questionnaire survey and
expert opinions. The swift Quantitative Microbial Risk Assessment (sQMRA) model was used to model the risk of exposure. The study was driven by the lack of research-based information in this area despite the increase in the number of reported cases of cholera in Lusaka Province. Results showed that the average serving portion for fresh fish in Lusaka District was 200g for fresh fish consumers in the restaurants and high socio-economic status households, while
100g were for the consumers in low socio-economic status households, respectively. The probability of exposure to Vibrio cholerae through consumption of fresh fish was estimated to be low. At serving portions of 100g and 200g in the low and high socio economic status households with a concentration of 50 cfu/g, infectious dose 50 (ID50) of 106 cells, one person would get ill, representing a probability of 0.000044%. At an average serving portion of 200g at restaurants level, 50cfu/g and ID50 of 106 cells, 47 people would get ill, translating into a probability of 0.0021% per year The study concludes that the risk of exposure to Vibrio cholerae among residents in Lusaka Province, as a result of fresh fish consumption, would be generally low, attributed to preparation methods. The study also revealed that cross-contamination during preparation and consumption could be a source of exposure to the Vibrio cholerae. Improvement in food hygiene practices and processing are needed to minimize the occurrence of foodborne illnesses. Further, work is required to broaden the scope of the study and also undertake a microbiological evaluation of fresh fish from both household and restaurant risk exposure pathways.