Characterization of Avian Influenza Virus H10–H12 Subtypes Isolated from Wild Birds in Shanghai, China from 2016 to 2019

Abstract

H10, H11 and H12 (H10–H12) subtypes of the avian influenza virus (AIV) are associated with waterfowl. Although these subtypes of AIV are infrequently detected in nature, they can undergo reassortment with other AIV subtypes. Few H10–H12 subtypes of AIV have been isolated from wild birds in China. In this study, 12 AIV isolates of H10–H12 subtypes were identified via routine surveillance of wild birds in Shanghai, China from 2016 to 2019, including two H10, three H11 and seven H12 isolates. Sequence and phylogenetic analyses revealed that the genomic segments of the 12 isolates are highly diverse. These 12 isolates are closely related to those in the Eurasian lineage and share a high degree of sequence identity with those from wild birds and domestic ducks in countries in the East Asian–Australasian Flyway, including Japan, Korea, Bangladesh, Vietnam and China. However, parts of the genomic segments of two H12N2 isolates (NH112319-H12N2 and NH101807-H12N2) belong to the North American lineage, suggesting intercontinental reassortment among H12 AIVs in Eurasia and North American. To better understand the ecological and phylodynamic features of H10–H12 subtypes in wild birds, a large-scale surveillance of AIVs in wild birds is warranted.

Emergence, Evolution, and Biological Characteristics of H10N4 and H10N8 Avian Influenza Viruses in Migratory Wild Birds Detected in Eastern China in 2020

“…H10Nx viruses, including the H10N3, H10N4, H10N7, and H10N8 viruses, have circulated in birds and mammals (minks and seals) in recent decades ( 21 – 25 ). H10 viruses have been reported to infect multiple avian species, and more than 1,600 H10 isolates have been identified and isolated from a wide range of wild birds (e.g., gulls, Anseriformes, and shorebirds), domestic waterfowl, and chickens ( 26 – 32 ).…”

Genetically Divergent Highly Pathogenic Avian Influenza A(H5N8) Viruses in Wild Birds, Eastern China

“…The birds showed no signs of illness. Reverse transcription PCR detected 32 H5N8 viruses by described procedures (12). We determined the prevalence of H5N8 viruses to be 5.2%.…”

The Emergence and Zoonotic Transmission of H10Nx Avian Influenza Virus Infections

“…They also continuously circulate in live-bird markets (LBMs) in Asia. Surveillance studies have indicated that terrestrial poultry were the root cause of H10Nx zoonotic transmission events in China beginning in 2012 ( 20 – 22 ). H10Nx viruses have a broad host range and are capable of reassorting with increased fitness for mammalian species ( 23 ).…”

“…H10 is an LPAIV in avian hosts, allowing undetected circulation and the development of reservoirs ( 45 , 51 ). An additional risk factor is the frequency of H10Nx reassortment ( 21 , 46 ). H10Nx viruses have reassorted with enzootic AIV strains, which subsequently caused human infection; an example is that chicken H10N8 viruses identified in China were generated through multiple reassortments between H10 and N8 viruses from domestic ducks and the enzootic chicken H9N2 viruses.…”