Infant foods as a potential source of diarrhoeal illness in rural West Africa.

It is common practice in rural areas of The Gambia to prepare infant foods in quantities which are sufficient to meet the needs of the day rather than one meal. These are then stored at ambient temperatures for periods up to 12 hours for feeding to the child on demand. The total viable counts and levels of Bacillus cereus, Clostridium welchii, Staphylococcus aureus and Escherichia coli were determined in 294 infant foods samples from nought to eight hours after preparation. The presence of Salmonella was determined in 10 g samples of food. In the first hour after preparation the proportion of foods dangerously contaminated was high during the rainsy season, significantly more so than during the dry season. Foods not consumed fresh were very often hazardous and almost always so after 8 hours. This problem may be a causal factor in weanling diarrhoea which also shows marked seasonal variation in prevalence.