The numbers and varieties of bacteria carried by filth flies in sanitary and unsanitary city area.

Filth flies caught with nets in various localities of varying sanitary conditions in Ibadan city were predominantly Musca domestica and a few Fannia cannicularis. Seven genera of bacteria, some of which were pathogenic to humans, were isolated from the legs, wings, mouthparts and midguts of the flies. Flies were very abundant in areas where unsanitary conditions prevailed and scarce where sanitary conditions were enforced. The total number of bacteria isolated from flies caught in the market places was higher than those isolated from flies caught in any other locality; low numbers of bacteria were isolated from flies caught in areas where hygienic conditions prevailed. Bacillus spp. were the most numerous of the bacteria isolated. The greatest numbers of bacteria were found on the legs. From the house-flies caught on dairy animals were isolated a high number of Escherichia coli. The public health significance of these findings is discussed.