Molecular Markers for Interspecies Transmission of Avian Influenza Viruses in Mammalian Hosts

Abstract

In the last decade, a wide range of avian influenza viruses (AIVs) have infected various mammalian hosts and continuously threaten both human and animal health. It is a result of overcoming the inter-species barrier which is mostly associated with gene reassortment and accumulation of mutations in their gene segments. Several recent studies have shed insights into the phenotypic and genetic changes that are involved in the interspecies transmission of AIVs. These studies have a major focus on transmission from avian to mammalian species due to the high zoonotic potential of the viruses. As more mammalian species have been infected with these viruses, there is higher risk of genetic evolution of these viruses that may lead to the next human pandemic which represents and raises public health concern. Thus, understanding the mechanism of interspecies transmission and molecular determinants through which the emerging AIVs can acquire the ability to transmit to humans and other mammals is an important key in evaluating the potential risk caused by AIVs among humans. Here, we summarize previous and recent studies on molecular markers that are specifically involved in the transmission of avian-derived influenza viruses to various mammalian hosts including humans, pigs, horses, dogs, and marine mammals.

Highly Pathogenic Avian Influenza A(H5N8) Virus in Gray Seals, Baltic Sea

“…Studies have shown that some mutations known to enhance the transmissibility of H5N1 HPAI viruses may increase the ability of LPAI viruses to be transmitted from bird to marine mammal ( 11 – 13 ). These factors include the change of sialic acid receptor binding affinity ( 11 ) and adaptive mutations in the vRNP complex for replication and virus spread in the seal population ( 12 ).…”

Inventory of molecular markers affecting biological characteristics of avian influenza A viruses

“…All available information on AIV molecular markers/mutations was collected from: the CDC H5N1 Genetic changes inventory [17], the WHO Working Group on Surveillance of Influenza Antiviral Susceptibility (WHO-AVWG) [18], and publications summarizing AIV mutations and molecular markers affecting biological characteristics and potential risk [19–21]. Journal articles were sourced for each specific subtype using PubMed searches with MeSH Terms, Boolean operators and wild cards.…”

Pathological and Molecular Characterization of H5 Avian Influenza Virus in Poultry Flocks from Egypt over a Ten-Year Period (2009–2019)

“…However, the species barrier can be broken by some AIV subtypes which can infect humans [ 5 , 6 ]. At least eight AIV subtypes have been reported to infect humans, resulting in human influenza pandemics (H1, H2, H3, H5, H6, H7, H9, and H10) [ 7 , 8 ]. Prior to 2013, H5N1, H5N2, H7N2, H7N3, H7N7, H9N2, and H10N7 AIVs were known to cause human infection, then H7N9, H6N1, H10N8, and H5N6 AIVs were also detected in humans [ 9 , 10 , 11 , 12 ].…”