A Molecular and Serological Study on Visceral Leishmaniasis in Asymptomatic Stray Dogs in Mashhad ,Iran

: Zoonotic visceral leishmaniasis is caused by Leishmania infantum (L. infantum),and its major reservoir hosts are domestic dogs, most of which are asymptomatic. This study aimed to detect L. infantum spp. in asymptomatic stray dogs by molecular and serological methods in Mashhad, Iran, during 2011-12. In this study, 94 asymptomatic stray dogs were randomly selected and their blood samples were collected for indirect fluorescent antibody testing. Furthermore, tissue samples from all the L. infantum seropositive stray dogs were examined using semi-nested polymerase chain reaction (PCR). Accordding to the results, 11.7 %(11/94) of the dogs were L. infantum seropositive. The PCR positivity rate of L. infantum was 63.6% (7/11) in at least one of the collected specimens of the seropositive dogs. The L. infantum kinetoplast DNA (kDNA) was detected in the liver of 36% (4/11), the spleen of 27% (3/11), and the skin of 54.5 %(6/11) of the stray dogs. In this study, based on the molecular and serological examinations, visceral leishmaniasis infection among the stray dogs in Mashhad was confirmed.