Serological Investigation Of Influenza Viruses Of Different Host Sources In Pet Dogs

Studies found that there were two sialic acid receptors in the respiratory system of dogs,namely SAα2,3Gal and SAα2,6Gal sialic acid receptors,which means that dogs can also be used as intermediate hosts to be infected with avian and human influenza virus.Recently,many studies have reported that different subtypes avian influenza virus(AIV),human influenza virus and swine influenza virus(SIV)could infect dogs and produced novel reassortant viruses in dog.Based on the intimate relationship between dogs and humans,understanding the prevalence of influenza A virus of different host sources in dogs,will be a great significance for human and public health.Our study will use the Eurasian avian H1N1(EA H1N1),Human-like H3N2(Hu H3N2)canine influenza virus(CIV),SIVs of different lineages,including pdm09/H1N1 lineage,EA H1N1 lineage,North American triple reassortant internal genes(TRIG)lineage,seasonal Human-like(Hu)lineage,and H5,H7 and H9 subtype AIV as antigens,hemagglutination inhibition(HI)and enzyme linked immunosorbent assay(ELISA)were employed to conduct a serological survey for 1054 dog sera collected from Guangxi from 2013 to 2018.The results found that influenza viruses of different lineages can detect antibodies in dogs.CIV-EA H1N1 virus displayed local epidemic in pet dogs in Guangxi,whose antibody positive rate in 2018 was higher and reached to 14.71%(84/571).Compared with other cities,Liuzhou owned highest infection rate which reached to 13.25%(31/234).Otherwise,the prevalence of SIVs in dogs was relatively limited by monitoring the infection of different lineages SIVs in dogs.The average antibody positive rate was only 2.17%.In particular,the seroprevalence of SIV-EA H1N1 was significantly lower than that of CIV-EA H1N1,which only reached to 2.17%.Serological surveillance for H5,H7 and H9 subtype AIVs in dogs revealed that H5,H7 and H9 subtype viruses were infectecd to a lower degree.The study firstly reports that the positive antibody of H7 subtype AIV in dogs,suggesting that the subtype can infect dogs.Additionally,there are co-infection of three subtypes AIVs in the same region,which will increase the possibility of viral reassortment in dogs and threaten the human health.