IMPLEMENTATION OF A REVERSE GENETICS METHOD FOR THE GENERATION OF LOW-PATHOGENIC CONTEMPORARY H3N2 INFLUENZA VIRUS

Abstract

In order to evade host immune pressures, influenza viruses evolve genetically and antigenically. Circulating H3N2 strains display this tendency resulting in increased infections and decreased vaccine efficacy. This variability makes selection of the recommended seasonal vaccine strains increasingly difficult, reducing the time researchers have to manufacture effective vaccines. The inaccessibility of new circulating H3N2 strains in WHO and CDC repositories underscores a need for improvements in the acquisition of virus to test antibody responses from vaccine strains within the clinical setting. Although thousands of the new H3N2 strains are sequenced per year, very few have been isolated with viral stocks made for them by the CDC, because of this, testing vaccine efficacy against these strains is impossible. Implementation of a reassortant reverse genetics platform can provide the recombinant virus samples necessary to enable insight into the effectiveness and range of antibodies produced from recommended vaccine strains. This allows testing the immune response following vaccination by evaluating the ability of serum antibodies to neutralize or inhibit hemagglutination of a wide array of antigenically distinct influenza strains particularly the H3N2 subtype circulating strains.