Huang D.T.-N.PEI-LAN SHAOKUO-CHIN HUANGCHUN-YI LUWang J.-R.Shih S.-R.Chi H.Lai M.-R.Lee C.-Y.LUAN-YIN CHANGLI-MIN HUANG2020-12-152020-12-1520111080-6040https://www.scopus.com/inward/record.uri?eid=2-s2.0-78650984565&doi=10.3201%2feid1701.100014&partnerID=40&md5=dbe62990084b7f04ba2de823ef20d314https://scholars.lib.ntu.edu.tw/handle/123456789/525593We studied preexisting immunity to pandemic (H1N1) 2009 virus in persons in Taiwan. A total of 18 (36%) of 50 elderly adults in Taiwan born before 1935 had protective antibodies against currently circulating pandemic (H1N1) 2009 virus. Seasonal influenza vaccines induced antibodies that did not protect against pandemic (H1N1) 2009 virus.[SDGs]SDG3cross reacting antibody; influenza vaccine; 2009 H1N1 influenza; adult; aged; antibody titer; article; blood sampling; child; human; immunity; influenza vaccination; Influenza virus A H1N1; major clinical study; preschool child; serology; Taiwan; Adult; Aged; Aged, 80 and over; Antibodies, Viral; Child, Preschool; Cross Protection; Cross Reactions; Humans; Influenza A Virus, H1N1 Subtype; Influenza Vaccines; Influenza, Human; Middle Aged; Pandemics; Seasons; Taiwan; Young Adultjournal article10.3201/eid1701.100014211928582-s2.0-78650984565