Prevalence of respiratory viruses isolated from dogs in Thailand during 2008-2009

Background: A highly contagious respiratory disease in canines is infectious tracheobronchitis or kennel cough characterized by inflammation of the upper respiratory tract. The cause of kennel cough has been associated with multiple or complex agents such as canine adeno virus (CAV), canine influenza virus (CIV), canine distemper virus (CDV), and canine para influenzavirus (CPIV). Objective: Study the prevalence of canine respiratory viruses detected from in Thailand during 2008-2009. Methods: Nasal swab samples collected from 102 healthy dogs and 109 dogs with respiratory diseases. Then CAV, CIV, CDV, and CPIV were detected by in-house nested PCR and further confirmed by nucleotide sequencing. Results: Nested PCR showed that primers designed and used in this study yielded high specificity without any non-specific amplification. The prevalence of CAV, CIV, CDV and CPIV in healthy dogs was 0%, 2.94%, 2.94%, and 0.98%, whereas that found in dogs with respiratory diseases was 9.17%, 1.83%, 2.75%, and 11.93%, respectively. In healthy dogs, co-infection with CPIV + CDV was detected in only 0.98%. On the other hand, dogs with respiratory symptoms showed multiple infections with CAV + CIV in 1.83%, CIV + CPIV in 0.92%, CAV + CPIV in 1.83%, and CAV + CDV + CPIV in 0.92%. Conclusion: The prevalence data obtained from this study may be useful for outbreak preventions and to raise awareness of potential transmission of the newly emerged canine influenza virus to humans.