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Clinical and immune responses to inactivated influenza A(H1N1)pdm09 vaccine in children.

ABSTRACT: As the influenza A H1N1 pandemic emerged in 2009, children were found to experience high morbidity and mortality and were prioritized for vaccination. This multicenter, randomized, double-blind, age-stratified trial assessed the safety and immunogenicity of inactivated influenza A(H1N1)pdm09 vaccine in healthy children aged 6 months to 17 years.Children received 2 doses of approximately 15 or 30 µg hemagglutin antigen 21 days apart. Reactogenicity was assessed for 8 days after each dose, adverse events through day 42, and serious adverse events or new-onset chronic illnesses through day 201. Serum hemagglutination inhibition titers were measured on days 0 (prevaccination), 8, 21, 29 and 42.A total of 583 children received the first dose and 571 received the second dose of vaccine. Vaccinations were generally well-tolerated and no related serious adverse events were observed. The 15 µg dosage elicited a seroprotective hemagglutination inhibition (? 1:40) in 20%, 47% and 93% of children in the 6-35 month, 3-9 year and 10-17 year age strata 21 days after dose 1 and in 78%, 82% and 98% of children 21 days after dose 2, respectively. The 30 µg vaccine dosage induced similar responses.The inactivated influenza A(H1N1)pdm09 vaccine exhibited a favorable safety profile at both dosage levels. While a single 15 or 30 µg dose induced seroprotective antibody responses in most children 10-17 years of age, younger children required 2 doses, even when receiving dosages 4- to 6-fold higher than recommended. Well-tolerated vaccines are needed that induce immunity after a single dose for use in young children during influenza pandemics.

SUBMITTER: Kotloff KL

PROVIDER: S-EPMC4166548 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Clinical and immune responses to inactivated influenza A(H1N1)pdm09 vaccine in children.

Kotloff Karen L KL Halasa Natasha B NB Harrison Christopher J CJ Englund Janet A JA Walter Emmanuel B EB King James C JC Creech C Buddy CB Healy Sara A SA Dolor Rowena J RJ Stephens Ina I Edwards Kathryn M KM Noah Diana L DL Hill Heather H Wolff Mark M

The Pediatric infectious disease journal 20140801 8

<h4>Background</h4>As the influenza A H1N1 pandemic emerged in 2009, children were found to experience high morbidity and mortality and were prioritized for vaccination. This multicenter, randomized, double-blind, age-stratified trial assessed the safety and immunogenicity of inactivated influenza A(H1N1)pdm09 vaccine in healthy children aged 6 months to 17 years.<h4>Methods</h4>Children received 2 doses of approximately 15 or 30 µg hemagglutin antigen 21 days apart. Reactogenicity was assessed ...[more]

PMID: 25222307

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Clinical and immune responses to inactivated influenza A(H1N1)pdm09 vaccine in children.

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Clinical and immune responses to inactivated influenza A(H1N1)pdm09 vaccine in children.

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