Prevalence of canine influenza virus A (H3N8) in dogs in Germany.

The aim of this study was to investigate the prevalence of CIV H3N8 in dogs in Germany. Blood samples from 272 clinically healthy dogs and 35 dogs with acute respiratory signs were screened for antibodies against influenza virus by ELISA and haemagglutination inhibition (HI) assay; positive samples were further tested by fluorescent antibody test (FAT) and subtype-specific HI assay. Nasal and pharyngeal swabs from all sick dogs were submitted for real-time (RT)-PCR for influenza virus RNA; PCR results were negative in all cases. One healthy and one sick dog tested positive for antibodies against influenza virus nucleoprotein by ELISA, but both were negative by subtype-specific HI assay and FAT, and were therefore considered false positive results. Thus, antibody prevalence against CIV H3N8 was 0% (0-1.24%, 95% CI). Currently, the risk for CIV H3N8 infection in the German dog population seems very low.