Comparison between Musca domestica and Chrysomya megacephala as carriers of bacteria in northern Thailand.

A comparison between the common house fly, Musca domestica, and the Oriental latrine fly, Chrysomya megacephala, was assessed for their potential as carriers of bacteria in urban areas of Chiang Mai Province, northern Thailand. C. megacephala was significantly more likely to carry bacterial species than M. domestica; however, no significant difference was found between the number of positive male and female flies within the same species. A total of 42 bacterial species were isolated. The most common bacterium isolated from M. domestica was coagulase-negative staphylococci (n=57) followed by Escherichia coli (n=10) and Viridans streptococci (n=10), while that of C. megacephala was non-fermentative gram-negative bacilli (n=59) followed by coagulase-negative staphylococci (n=54).