Table 1. Influenza virus and vaccine reassortant strain differences in protein sequence.

Influenza sequences were retrieved from the National Center for Biotechnology Information (NCBI) Influenza Virus Resource (75) querying by the strains for A(H1N1)pdm09 virus (A/California/07/2009) and for vaccine reassortants (X-179A and X-181) with duplicate sequences removed. Each influenza protein expected to be present in the vaccine preparations (M1, NP, HA, and NA) was compared across strains, and identified three sequences where X-181 differed from X-179A by at least one residue. Sequences identified for X-179A were similar to those of A(H1N1)pdm09 virus. Residues that vary are underlined.

ProteinGenbank accessionSourceSequence
HAACR47014X-179A136 KTSSWPNHDSNKGVTAACPHA
AFM72842X-181136 KTSSWPNHDSDKGVTAACPHA
NPADE29096X-179A106 RELILYDKEEIRRIWRQANNG
AFM72846X-181106 RELILYDKEEMRRIWRQANNG
ADE29096X-179A130 WRQANNGDDAAAGLTHMMIWH
AFM72846X-181130 WRQANNGDDATAGLTHMMIWH