Fig. 4.
Three-dimensional antigenic map of influenza A(H1N1)pdm09 (on the left) and A(H3N2) (on the right) viruses that circulated in Russia in the season 2018–2019. NOTE: grey or red spheres indicated with red symbols—reference antigens; grey cubes/squares indicated with blue symbols—reference antisera; green spheres indicated with bold black symbols—old test antigens (2013–2017); orange circles—test antigens season 2018–2019. One map square represents a twofold difference in HI titre