Seroprevalence of Influenza A in Domestic Dogs in Thailand, 2013

Abstract

Canine influenza viruses (CIVs) have been reported in dogs worldwide. Due to the relatively high risk of influenza A virus (IAV) infections in dogs and humans through dog-human interface, the seroprevalence of IAVs in dogs in Thailand was surveyed. A serological survey of IAV infections in dogs in Thailand was conducted from December 2012 to November 2013 using ELISA assays for detecting anti-nucleoprotein (NP) antibodies (NP-ELISA) and hemagglutination inhibition (HI) tests for detecting HA-specific antibodies using canine H3N2 (CIV-H3N2), human pandemic H1N1 2009 (Human-pH1N1) and human seasonal H3N2 (Human-H3N2) as viral antigens. A total of 9,891 serum samples were obtained from healthy and sick dogs of any breed, age and gender. The samples were collected weekly for 52 weeks from 467 veterinary clinics and hospitals located in 15 central provinces of Thailand. The survey of IAV infections in dogs showed that 164 (1.66 %) of the 9,891 serum samples had antibodies to IAV by NP-ELISA. Of the 164 positive samples from NP-ELISA, 12.20%, 23.17% and 1.22% had HI titers for CIV-H3N2, Human-pH1N1 virus and Human-H3N2, respectively. Thai dogs showed the highest seropositivity rate for Human-pH1N1. These results suggest that Human-pH1N1 is the dominant subtype circulating in Thai pet dogs. Our study highlights the risk of pH1N1 and CIV infections in dogs. Routine monitoring of IAV infections in dogs should be conducted.