Antigenic Cartography of H9 Avian Influenza Virus and Its Application to Vaccine Selection.
Vaccination is frequently used as a control method for the H9 subtype of low pathogenicity avian influenza virus (AIV), which is widespread in Asia and the Middle East. One of the most important factors for selecting an effective vaccine strain is the antigenic match between the hemagglutinin protein of the vaccine and the strain circulating in the field. To demonstrate the antigenic relationships among H9 AIVs, with a focus on Israeli H9 isolates, antigenic cartography was used to develop a map of H9 AIVs. Based on their antigenic diversity, three isolates from Israel were selected for vaccination-challenge studies: 1) the current vaccine virus, A/chicken/Israel/215/2007 H9N2 (Ck/215); 2) A/chicken/Israel/1163/2011 H9N2 (Ck/1163); and 3) A/ostrich/Israel/1436/2003 (Os/1436). A 50% infective dose (ID50) model was used to determine the effect of the vaccines on susceptibility to infection by using a standardized dose of vaccine. Sera collected immediately prior to challenge showed that Ck/215 was the most immunogenic, followed by Ck/1163 and Os/1436. A significant difference in ID50 was only observed with Ck/215 homologous challenge, where the ID50 was increased by 2 log 10 per bird. The ID50 for Ck/1163 was the same, regardless of vaccine, including sham vaccination. The ID50 for Os/1436 was above the maximum possible dose and therefore could not be established.
A Southeast Poultry Research Laboratory, United States Department of Agriculture, Agricultural Research Service, 934 College Station Road, Athens, GA 30605.
Yue
Y
Wang
B Kimron Veterinary Institute, P.O. Box 12, Bet Dagan, 50250, Israel.
Irit
I
Davidson
C Department of Viroscience, Erasmus Medical Center, P.O. Box 2040, Rotterdam, the Netherlands 3000 CA.
Ron
R
Fouchier
A Southeast Poultry Research Laboratory, United States Department of Agriculture, Agricultural Research Service, 934 College Station Road, Athens, GA 30605.
Erica
E
Spackman
D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D000940:Antigenic Variation; D001717:Birds; D002645:Chickens; D053127:Influenza A Virus, H9N2 Subtype / Q000235:genetics / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D011201:Poultry Diseases / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D014611:Vaccination
D000914:Antibodies, Viral; D007252:Influenza Vaccines
H9N2 influenza; antigenic cartography; low pathogenic avian influenza virus; poultry disease