Safety and immunogenicity of an inactivated split-virus influenza A/H1N1 vaccine in healthy children from 6 months to <18 years of age: A prospective, open-label, multi-center trial

Chi Eun Oh, Jina Lee, Jin Han Kang, Young Jin Hong, Yun Kyung Kim, Hee-Jin Cheong, Young Joo Ahn, Sang Hoon Kim, Hoan Jong Lee

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33 Citations (Scopus)


This study was conducted to determine the immunogenicity and safety of an inactivated split-virus influenza A/H1N1 vaccine in healthy Korean children from 6 months to <18 years of age. The immunization schedule consisted of two vaccinations, 21 days apart. The unadjuvanted vaccine contained 7.5μg (subjects 6 months to <3 years of age) or 15μg (subjects 3 to <18 years of age) of hemagglutinin antigen per dose. A total of 251 subjects were enrolled and 248 and 242 subjects, respectively, were included in the post-first dose and post-second dose immunogenicity evaluations conducted on a per protocol basis. By day 21, after the first dose, hemagglutination-inhibition titers of 1:40 or more were observed in 5.9% of subjects 6 months to <3 years of age, 34.9% of subjects 3 to <9 years of age and 81.4% of subjects 9-18 years of age. By day 21 after the second dose, the titer had been achieved 55.9%, 69.5% and 90.5%, respectively. No vaccination-related serious adverse events were observed. A single 15-μg dose of vaccine was highly immunogenic in subjects equal to or more than 9 years of age. However, a two-dose regimen is needed to produce potentially protective antibody titers in younger children.

Original languageEnglish
Pages (from-to)5857-5863
Number of pages7
Issue number36
Publication statusPublished - 2010 Aug 1



  • H1N1 virus
  • Influenza vaccine
  • Pandemic

ASJC Scopus subject areas

  • Molecular Medicine
  • Immunology and Microbiology(all)
  • veterinary(all)
  • Public Health, Environmental and Occupational Health
  • Infectious Diseases

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