House fly (Musca domestica) as a transport vector of Cryptosporidium parvum

Abstract

Synanthropic filth flies are a likely vehicle of transmission of human cryptosporidiosis. A polymerase chain reaction assay specific for the 18S rRNA gene of Cryptosporidium parvum Tyzzer, 1912 and C. wrairi Vetterling, Jervis, Merrill et Sprinz, 1971 was used for the direct detection of Cryptosporidium DNA in Musca domestica L. flies captured in two towns in Aragon (Spain). Six hundred flies were clustered in groups of ten and processed. An amplification product of the expected size (422 base pairs) was detected in 11 of the 60 groups (18%). Cryptosporidium parvum is an enteric coccidian parasite of mammals, including humans; it is frequently detected in young livestock. In humans, cryptosporidiosis is recognised as a common cause of acute transient diarrhoea. Transmission of oocysts excreted from infected hosts occurs either by direct host-to-host contact or indirectly by contaminated water or food; other indirect transmission mechanisms (for example arthropods) have not been sufficiently studied. Cryptosporidium parvum oocysts have been detected in flies, both