Serological evidence of canine influenza virus infection in shelter dogs in Turkey

Influenza virus infection is an important disease which occurs in humans and a variety of animals. Because of the wide host adaptation and segmented genome, there is always the possibility of mutations and interspecies transmission of the influenza virus. Our study is the first to draw attention to canine influenza infection in Turkey. For this purpose, 208 sera and swab samples were collected from dogs with respiratory and non-respiratory signs in various seasons. Out of the 208 dogs, 94 (45.2%) were male and 114 (54.8%) were female; the average age was 4.7 years. A total of 208 sera samples were tested for the presence of canine influenza virus-specific antibodies by the indirect enzyme-linked immunosorbent assay. The seroprevalence of canine influenza virus infection was 11/208 (5.8%). With regard to seasonal distribution, the highest rate of seropositivity was detected in spring, and the lowest in summer. Molecular detection of the canine influenza virus from nasal swab samples was done by reverse transcriptase polymerase chain reaction using specific universal primers for the hemagglutinin gene. Influenza virus nucleic acid could not be detected by reverse transcriptase polymerase chain reaction. In this study, we revealed for the first time the existence of the canine influenza virus in Turkey. Although the seroprevalence was relatively low, it would be useful to investigate the canine influenza virus on a large scale and among dogs with infectious respiratory disease in the Turkish dog population.