TY - JOUR AU - Vandoorn, Elien AU - Leroux-Roels, Isabel AU - Leroux-Roels, Geert AU - Parys, Anna AU - Vincent, Amy AU - Van Reeth, Kristien T1 - Detection of H1 Swine Influenza A Virus Antibodies in Human Serum Samples by Age Group T2 - Emerging Infectious Disease journal PY - 2020 VL - 26 IS - 9 SP - 2118 SN - 1080-6059 AB - Most H1 influenza A viruses (IAVs) of swine are derived from past human viruses. As human population immunity against these IAVs gradually decreases, the risk of reintroduction to humans increases. We examined 549 serum samples from persons 0–97 years of age collected in Belgium during 2017–2018 for hemagglutination inhibiting and virus neutralizing antibodies against 7 major H1 swine IAV (swIAV) clades and 3 human progenitor IAVs. Seroprevalence (titers >40) rates were >50% for classical swine and European human-like swIAVs, >24% for North American human-like δ1a and Asian avian-like swIAVs, and <10% for North American human-like δ1b and European avian-like swIAVs, but rates were age-dependent. Antibody titers against human-like swIAVs and supposed human precursor IAVs correlated with correlation coefficients of 0.30–0.86. Our serologic findings suggest that European avian-like, clade 1C.2.1, and North American human-like δ1b, clade 1B.2.2.2, H1 swIAVs pose the highest pandemic risk. KW - influenza KW - humans KW - swine KW - hemagglutinins KW - antibodies KW - hemagglutination inhibition tests KW - pandemic KW - public health KW - viruses KW - zoonoses KW - hemagglutinin KW - hemagglutination inhibition DO - 10.3201/eid2609.191796 UR - https://wwwnc.cdc.gov/eid/article/26/9/19-1796_article ER - End of Reference