Feline cuterebrosis caused by a lagomorph-infesting Cuterebra spp. larva

Native species of rodents and lagomorphs in the Americas are the typical hosts of Cuterebra spp. larvae. Although these bot flies are relatively host specific, they occasionally parasitize other native and introduced mammals (including domestic animals and humans), an affliction termed cuterebrosis. Cuterebra spp. larvae generally cause benign, subcutaneous lesions (warbles), but when infesting domestic cats, they can invade the eyes, respiratory tract, and cerebral tissues, causing severe, and in some cases fatal, injury. Despite more than 2 dozen published reports of feline cuterebrosis, the type (rodent- or lagomorph-infesting) or species parasitizing domestic cats has rarely been determined. Here, I identify a larva removed from a kitten in southern Wisconsin as belonging to a lagomorph-infesting Cuterebra species, most likely C. abdominalis, based especially on features of the cuticular platelets covering its exterior, and its geographic location. This seems to be only the third substantiated report of feline cuterebrosis in more than 50 yr in which a larva has been identified beyond "Cuterebra spp." In each case, lagomorph-infesting species were involved, suggesting that domestic cats may not be susceptible to rodent-infesting Cuterebra species. However, because these studies are limited in number and geographic area, additional research is required to establish the spectrum of Cuterebra species involved in feline cuterebrosis.