Interspecies and intraspecies transmission of influenza A viruses: viral, host and environmental factors.
Influenza A viruses are enveloped viruses belonging to the family Orthomyxoviridae that encompasses four more genera: Influenza B, Influenza C, Isavirus and Thogotovirus. Type A viruses belong to the only genus that is highly infectious to a variety of mammalian and avian species. They are divided into subtypes based on two surface glycoproteins, the hemagglutinin (HA) and neuraminidase (NA). So far, 16 HA and 9 NA subtypes have been identified worldwide, making a possible combination of 144 subtypes between both proteins. Generally, individual viruses are host-specific, however, interspecies transmission of influenza A viruses is not uncommon. All of the HA and NA subtypes have been isolated from wild birds; however, infections in humans and other mammalian species are limited to a few subtypes. The replication of individual influenza A virus in a specific host is dependent on many factors including, viral proteins, host system and environmental conditions. In this review, the key findings that contribute to the transmission of influenza A viruses amongst different species are summarized.
Yassine
Hadi M
HM
Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, 44691, USA.
Lee
Chang-Won
CW
Gourapura
Renukaradhya
R
Saif
Yehia M
YM
D000818:Animals; D017753:Ecosystem; D054884:Host-Pathogen Interactions; D009980:Influenza A virus / Q000145:classification* / Q000472:pathogenicity / Q000502:physiology*; D009976:Orthomyxoviridae Infections / Q000635:transmission / Q000662:veterinary* / Q000821:virology; D013045:Species Specificity; D014779:Virus Replication