The 1918 pandemic didn't end until 1957. The virus came back as seasonal influenza until it was eventually displaced by H2N2 (as H1N1 displaced whatever influe

The 1918 pandemic didn't end until 1957. The virus came back as seasonal influenza until it was eventually displaced by H2N2 (as H1N1 displaced whatever influenza was around pre-1918). That H1 envelope protein came back in the 2009 pandemic and has been with us ever since.