Update on avian influenza and role for vaccination of poultry

Authors: Suarez, David; Spackman, Erica; Pantin Jackwood, Mary; Lee, Chang

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/29/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The U.S. is experiencing a major outbreak of H5N1 highly pathogenic avian influenza that has resulted in a loss of over 60 million chickens and turkeys from disease or as part of the control efforts. The virus is primarily being transmitted from infected wild birds, probably wild waterfowl, to commercial farms. In an effort to better understand the outbreak virus, studies were conducted with one of the early wild bird viruses as well as two earlier highly pathogenic avian influenza viruses. All the viruses were highly pathogenic to chickens and turkeys, although chickens died earlier than turkeys given the same dose. Despite the high virulence, the virus did not transmit efficiently to contact control chickens. The virus was more transmissible to contact control turkeys. Because of the widespread transmission of the virus in wild birds, interest in vaccination in poultry has greatly increased. Several different commercial vaccines are potential available. Using the same or similar vaccines after the 2014-2015 H5 outbreak viruses, we have considerable laboratory experience that shows the vaccines, particularly in combination, can be effective at preventing clinical disease but not prevent infection and virus shedding. The major impediment to use of vaccination is the negative affects on trade. The use of DIVA vaccination may overcome this, but more work needs to be done to validate this principal before it is accepted as a tool to facilitate trade.