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Seasonal Trivalent Inactivated Influenza Vaccine Does Not Protect Against Newly Emerging Variants of Influenza A (H3N2v) virus in Ferrets.

Influenza Division, National Center for Immunization and Respiratory Diseases, Center for Disease Control and Prevention, Atlanta, GA 30333.
Journal of Virology (Impact Factor: 4.65). 10/2012; 87(2). DOI: 10.1128/JVI.02625-12
Source: PubMed

ABSTRACT The recent increase in human cases with influenza A H3N2 variant virus [A(H3N2)v] highlights the need to assess whether seasonal influenza vaccination provides cross-protection against A(H3N2)v virus. Our data demonstrate that the 2011-2012 trivalent inactivated influenza vaccine (TIV) protected ferrets against homologous H3N2 virus challenge, but provided minimal to no protection against A(H3N2)v virus. The complete absence of specific hemagglutination-inhibition antibody response to A(H3N2)v is consistent with the poor cross-protection observed among TIV-immune animals.

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