In a recent announcement Wageningen Bioveterinary Research, a component of Wageningen University will evaluate three commercial vaccines against H5N1 HPAI in laying hens. These products will be compared with experimental vaccines developed using advanced molecular technology. The E.U. is actively evaluating vaccination as an adjunct to biosecurity and depopulation of affected flocks as a coordinated approach to controlling HPAI.
The evaluation will be conducted over three months and vaccines will be compared as to their ability to suppress mortality and clinical signs and more important, to reduce virus shedding. To be acceptable to E.U. regulators, vaccines must prevent multiplication and excretion of virus that would be responsible for persistent infection. This is especially important in areas with a high concentration of domestic poultry as in the Netherlands, and regions of Germany, Poland, the U.K. and in the U.S.
In past years, Avian Influenza was a sporadic disease introduced by migratory waterfowl and was justifiably regarded as exotic in most industrialized nations. Accordingly, an approach involving rapid diagnosis and depopulation with quarantine restrictions was and is appropriate. Since 2020, the H5N1 strain of Avian Influenza carrying Eurasian genes has proven to be more extensive in geographic distribution. The current panornitic has affected a wide range of migratory and domestic birds, resulting in prolonged and recurrent outbreaks extending from November 2021 through the present. The experience in the E.U. is reflected in outbreaks in the U.S., dealing with essentially the same viral pathogen.
Clearly the results of studies in the E.U. and in other areas where HPAI can now be regarded as either seasonally endemic or de facto endemic will be of value to regulators in the U.S. Given the severity of the current U.S. epornitic and with poultry industries facing a worldwide panornitic, vaccination must be considered as an option. This will require relaxation of trade restrictions, modifying bans on importation to the county or regional level in nations experiencing outbreaks.
EGG-NEWS maintains that Avian Influenza is effectively the Newcastle disease of the 2020s. With the exception of Scandinavia, the disease is effectively controlled by applying a range of live attenuated, inactivated and vectored vaccines.