Seroepidemiological Evidence of Avian Influenza A Virus Transmission to Pigs in Southern China

Abstract

Recently, three novel avian-origin swine influenza viruses (SIVs) were first isolated from pigs in Guangdong Province, southern China, yet little is known about the seroprevalence of avian influenza viruses among pigs in southern China. Here, we report for the first time the seroprevalence of avian H3, H4, and H6 influenza viruses in swine populations and the lack of seroepidemiological evidence of avian H5 influenza virus transmission to pigs in China.

Avian-Like A (H1N1) Swine Influenza Virus Antibodies among Swine Farm Residents and Pigs in Southern China

“…The environment and lifestyle on swine farms in southern China facilitates close contact between domestic poultry, pigs, and humans, increasing the likelihood of interspecies transmission and generation of novel influenza viruses through reassortment (11,14,15). A number of influenza viruses have been isolated in the past from pigs in southern China, including the classical swine H1N1, human-like H1N1, avian-like H1N1, and human-like H3N2 viruses; the double-reassortant H3N2 virus containing genes from human and avian influenza viruses; the triple-reassortant H3N2 virus containing …”

“…genes from human, classical swine, and avian viruses; the avian-like H9N2 viruses; and the double-reassortant H1N2 virus containing genes similar to those found in swine and human viruses (10,11,(13)(14)(15). Southern China has been one of the epicenters of influenza epidemics (pandemics) throughout history (15), with Guangdong, Zhejiang, Fujian, and Yunnan provinces being on the frontlines of these epidemics owing to their large swine production industries.…”

“…Southern China has been one of the epicenters of influenza epidemics (pandemics) throughout history (15), with Guangdong, Zhejiang, Fujian, and Yunnan provinces being on the frontlines of these epidemics owing to their large swine production industries. Moreover, neither seasonal influenza vaccines nor pandemic 2009 H1N1 vaccines have been programmatically distributed to swine farm populations in these areas; therefore, the surveillance results should reflect the natural influenza virus infection rates among the swine farm populations of these four provinces (15,16). EA SIVs first appeared among pigs in China was in 2006 and have become prevalent since then (3,12,13).…”

Serological report of pandemic and seasonal human influenza virus infection in dogs in southern China

“…Susceptibility to influenza A virus infection is dependent on the characteristics of the virus and the host [1,2]. Influenza A viruses are subtyped on the basis of the antigenic properties of their hemagglutinin (HA) and neuraminidase (NA) glycoproteins expressed on the viral surface.…”

A Combination of HA and PA Mutations Enhances Virulence in a Mouse-Adapted H6N6 Influenza A Virus

“…Approximately one-third of H6 viruses isolated from live poultry markets in southern China could bind to human-type receptors, many could replicate in mice, and some could transmit efficiently among guinea pigs (9). Serological surveys conducted in China and America indicated that H6 influenza viruses might have previously infected swine and humans (10,11), and one-third of human volunteers inoculated with H6N1 or H6N2 viruses showed mild clinical symptoms with virus shedding (12). H6N1 viruses caused significant morbidity and mortality in mice without prior adaptation (13), and an H6N5 virus was lethal to mice and could be transmitted between ferrets by direct contact (14).…”