Evidence that flies contribute to the transmission
of the diarrhoeal disease agents has been reviewed
by Esrey.J Many pathogens that cause diarrhoea in
humans, including V. cholerae, Shigella spp., campylobacter,
E. coli, poliovirus, and Entamoeba histolytica,
can be recovered from flies, and many pathogens
can survive on the integument of flies for up to
10 days. Pathogens can also be carried in the gut of
flies and deposited on food when they regurgitate or
deposit excreta. Although, Esrey was unable to
conclude that they play a role in the transmission of
diarrhoeal diseases, flies are a potential source of
contamination of food and water. Several studies
have also reported the presence of infected domestic
animals in household premises (44), presenting an
additional risk factor for the contamination of food.