Prevalence of Dirofilaria immitis microfilariae in dogs from the State of São Paulo.

Abstract

The prevalence of Dirofilaria immitis microfilariae in dogs from the State of S.o Paulo was investigated by the fresh drop of blood method  and by the modified Knott technique.A total number of 511 blood samples were collected from, mixed and pure breed, adult dogs brought to the Veterinary Hospital of the Faculty of Veterinary Medicine of the University of S.o Paulo, or from private offices and from the coast-city Ubatuba. After performing both tests, the following data were obtained: 80 (15.65%) samples were positive for microfilariae, among them, 45 (8 .8%) were positive for D. immitis microfilariae; 33 (6.45%) were positive for Dipetalonema sp. microfilariae and 2 (0.39%) were positive for both of them. It could be concluded that the prevalence of canine dirofilariasis in the State of S.o Paulo has increased during the past 10 years if compared to a previous study with revealed a prevalence of 0.5% (1/226).