|NGUYEN, DIEP THI - National Center For Veterinary Diagnostics|
|SHEPARD, SAMUEL - Centers For Disease Control And Prevention (CDCP) - United States|
|BURKE, DAVID - Cambridge University|
|JONES, JOYCE - Centers For Disease Control And Prevention (CDCP) - United States|
|NGUYEN, LONG VAN - Ministry Of Agriculture And Rural Development (MARD)|
|THOR, SHARMI - Centers For Disease Control And Prevention (CDCP) - United States|
|NGUYEN, THO DANG - National Center For Veterinary Diagnostics|
|BALISH, AMANDA - Centers For Disease Control And Prevention (CDCP) - United States|
|HOANG, DANG NGUYEN - National Center For Veterinary Diagnostics|
|TO, THANG LONG - Ministry Of Agriculture And Rural Development (MARD)|
|IQBAL, MUNIR - The Pirbright Institute|
|WENTWORTH, DAVID - Centers For Disease Control And Prevention (CDCP) - United States|
|VAN DOORN, ROGIER - Oxford University|
|DAVID, TODD - Centers For Disease Control And Prevention (CDCP) - United States|
|BRYANT, JULIET - Oxford University|
Submitted to: Emerging Microbes & Infections
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/18/2018
Publication Date: 5/31/2018
Citation: Nguyen, D., Shepard, S.S., Burke, D.F., Jones, J., Nguyen, L., Thor, S., Nguyen, T., Balish, A., Hoang, D., To, T., Iqbal, M., Wentworth, D., Spackman, E., Van Doorn, R., David, T.C., Bryant, J.E. 2018. Antigenic characterization of highly pathogenic avian influenza A(H5N1) viruses with chicken and ferret antisera reveals similar haemagglutination inhibition profiles. Emerging Microbes & Infections. 7(1):1-14. https://doi.org/10.1038/s41426-018-0100-7.
Interpretive Summary: Bird flu is a worldwide threat to poultry health. Viet Nam is a country that has been affected particularly badly over the past decade. Vaccination of poultry has become routine to control the virus and preserve animal health. Because the virus mutates over time vaccines lose their ability to protect and must be updated. One way to select the best replacement for a vaccine is to test how the immune system sees the potential vaccine as compared to the virus strains in the field. Here viruses from Viet Nam are mapped using anti-serum from both chickens and ferrets. First, this shows that chicken serum provides similar results to ferret serum. This is important because chickens are easier to work with. Second, this provides a map of bird flu as it has evolved in Viet Nam and shows which vaccines may protect against which wild type viruses. This information will lead to much better and up-to-date vaccines in the region.
Technical Abstract: Highly pathogenic avian influenza (HPAI) A(H5N1) viruses pose a significant economic burden to the poultry industry worldwide and have pandemic potential. Poultry vaccination against HPAI A(H5N1) viruses has been an important component of HPAI control measures and has been performed in Vietnam since 2005. To systematically assess antigenic matching of current vaccines to circulating field variants, we produced a panel of chicken and ferret antisera raised against historical and contemporary Vietnamese reference viruses representing clade variants that were detected between 2001 and 2014. The antisera were used for hemagglutination inhibition (HI) assays to generate data sets for analysis by antigenic cartography, allowing for a direct comparison of results from chicken or ferret antisera. HI antigenic maps, developed with antisera from both hosts, revealed varying patterns of antigenic relationships and clustering of viruses that were dependent on the clade of viruses analyzed. Antigenic relationships between existing poultry vaccines and circulating field viruses were also aligned with in vivo protection profiles determined by previously reported vaccine challenge studies. Our results establish the feasibility and utility of HPAI A(H5N1) antigenic characterization using chicken antisera and support further experimental and modeling studies to investigate quantitative relationships between genetic variation, antigenic drift and correlates of poultry vaccine protection in vivo.