Viruses used in serological studies.

<p>Unless otherwise indicated, serologic study was performed using the microneutralization assay.</p><p>Virus studied with hemagglutination inhibition assay</p><p>Highly pathogen virus</p><p>Similar to 2009 pandemic H1N1 virus.</p><p>Virus of avian origin but cultured from a man.</p

Distribution of antibody titers against equine and avian influenza viruses among Mongolian participants, 2008–2011.

<p>0 mo = enrollment; 12 mo = 12 month annual follow-up; 24 mo = 24 month annual follow-up.</p

Study participants with detectable microneutralization assays titers against A/Equine/Mongolia/01/2008(H3N8) or A/Hong Kong/1073/1999(H9N2), with seroconversions.

<p>enroll = enrollment; 12 mo = 12 month annual follow-up; 24 mo = 24 month annual follow-up;</p><p> = 4-fold rise in titer between 2 timer periods;</p