An investigation of the microbiological chain of contamination and health implications of fish products from Lake Chivero, Harare, Zimbabwe

Abstract

A study to determine contamination of fish from Lake Chivero was carried out at selected sites along the fish handling and distribution chain. Samples were collected from lake and vending sites in Harare's high density suburbs, in March, August and November 2012. Pathogenic bacteria indicators were used to investigate the quality of water, fish, and fish contact surfaces to determine the levels of contamination. Swabs on contact surfaces and fish samples were tested for total viable bacterial count, coliforms and Salmonella. The highest coliforms load was recorded in fish trading locations and the lowest in the cold chain samples (Table 1). Salmonella sp. was present in most samples except harvest waters (Table 1). Pathogenic indicator micro-organisms were present in lake water samples (Table 1), suggesting that fish may already be contaminated. The increase in microbial load along the fish handling chain showed poor fish handling was causing additional contamination, presenting a health risk to consumers.