Susceptibility of wild passerines to subtype H5N1 highly pathogenic avian influenza viruses

Abstract

Highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype have spread throughout many areas of Asia, Europe and Africa, and numerous cases of HPAI outbreaks in domestic and wild birds have been reported. Although recent studies suggest that the dissemination of H5N1 viruses is closely linked to the migration of wild birds, information on the potential for viral infection in species other than poultry and waterfowl is relatively limited. To investigate the susceptibility of terrestrial wild birds to infection with H5N1 HPAI viruses, common reed buntings (Emberiza schoeniclus), pale thrushes (Turdus pallidus) and brown-eared bulbuls (Hypsipetes amaurotis) were infected with A/mountain hawk-eagle/Kumamoto/1/07(H5N1) and A/whooper swan/Aomori/1/08(H5N1). The results showed that common reed buntings and brown-eared bulbuls were severely affected by both virus strains (100% mortality). While pale thrushes did not exhibit any clinical signs, seroconversion was confirmed. In common reed buntings, intraspecies-transmission of A/whooper swan/Aomori/1/08 to contact birds was also confirmed. The findings show that three passerine species; common reed buntings, brown-eared bulbuls and pale thrushes are susceptible to infection by H5N1 HPAI viruses, which emphasizes that continued surveillance of species other than waterfowl is crucial for effective monitoring of H5N1 HPAI virus outbreaks.

Matched case-control study of the influence of inland waters surrounding poultry farms on avian influenza outbreaks in Japan

“…Inland waters surrounding poultry farms have been considered one of the risk factors of HPAI outbreaks since they provide suitable habitats for wild animals, including waterfowl 12 – 14 , 17 . Waterfowl migrating to inland waters may directly contaminate nearby farms, or contaminate the environments near inland waters, and small animals, such as resident birds and rodents, or humans may carry the viruses once they have been in contact with those contaminated environments and farms 19 – 21 .…”

“…In those studies, inland waters including lakes and wetlands usable by waterfowl were considered as one of the important risk factors of disease spread in the surrounding area. If waterfowl carry viruses, inland waters could become a site of infection of the HPAI virus to other vectors (e.g., resident birds or rodents) or fomites carrying the virus into nearby farms 19 – 21 .…”

Urban Chickens as a Pathway for Human Illness: An Examination of Knowledge, Behavior and Risk

“…The fourth category of literature addressing poultry diseases focuses on transmission between wild birds and poultry (see: [11,27,28]). Within this body of work is a sub-set of studies that focus purposely on the transmission of the H5N1 avian influenza between passerines and chickens [29,30]. This research points to the fact that concern exists in and around aspects of zoonotic transmission of avian diseases.…”

Parasitofauna survey of song thrushes (Turdus philomelos) from the eastern part of Spain

“…[3][4][5]. These birds have been widely studied as reservoirs of some viral pathogens (e.g., highly pathogenic influenza aviar and usutu virus; [6,7]), but it is still unclear their role as reservoir of parasites for domestic poultry, humans or other game bird species. In this sense, factors like seasonal migration, habitat changes or thrushes' diet (mainly based on insects, earthworms, snails, etc.…”