Oestrus ovis infestation of a dog in the UK.

In March 2011, a dog on a sheep farm in the Cotswolds, UK, expelled a mature live third-stage larva of the sheep nasal botfly, Oestrus ovis, after a violent and traumatic sneezing episode. The dog had been infected with first-stage larvae deposited by an adult fly the previous autumn; larval development had progressed throughout the winter and spring with few apparent clinical signs and possibly masked by ongoing immunotherapy for an unrelated condition. Identification of the parasite at the Liverpool School of Veterinary Science was made from a submitted puparium, the "chrysalis" stage to which the larva had progressed within days of its expulsion from dog's nose. To the authors' knowledge this is the first report of nasal botfly infestation of a dog in the UK.