2009 H1N1 vaccine can be co-administered with the 2009—10 seasonal influenza vaccine

January 01, 0001

2009 H1N1 vaccine can be co-administered with the 2009—10 seasonal influenza vaccine

With the ongoing 2009 pandemic of influenza A H1N1, development of pandemic influenza vaccines has generated much interest. The researchers from Hungary investigated the safety and immunogenicity of a whole-virion, inactivated, pandemic H1N1 vaccine in adult and elderly volunteers, given without or simultaneously with the 2009—10 seasonal trivalent influenza vaccine. 355 participants with stratification by age were assigned to either 0•5 mL of the pandemic vaccine (Fluval P, a monovalent vaccine with 6 microg haemagglutinin per 0•5 mL content and aluminium phosphate gel adjuvant, n=178) or 0•5 mL of the pandemic vaccine and 0•5 mL of the seasonal trivalent vaccine (Fluval AB, a trivalent inactivated whole-virion influenza vaccine, n=177).

Participants in both groups developed antibody responses against the pandemic influenza A H1N1 virus (group 1-seroconversion for adults 74•3% and for elderly people 61•3%, group 2-76•8% and 81•8%, respectively). Single doses of 6 mcg fulfilled European Union and US licensing criteria for interpandemic and pandemic influenza vaccines. Simultaneously, participants in group 2 developed the immune responses needed for licensing for all three seasonal strains in the seasonal vaccine for the 2009—10 season. Adverse events were rare, mild, and transient, most frequently pain at injection site and fatigue for 1—2 days after vaccination

The authors concluded: “The present pandemic vaccine is safe and immunogenic in healthy adult and elderly patients, and needs low doses and only one injection to trigger immune responses to comply with licensing criteria. It can be safely co-administered with the 2009—10 seasonal influenza vaccine.”

Sounds cost-effective as well.


For the full abstract, click here.

The Lancet 375(9708):49-55, 2 January 2010. © 2010 to Elsevier Ltd.
Safety and immunogenicity of a 2009 pandemic influenza A H1N1 vaccine when administered alone or simultaneously with the seasonal influenza vaccine for the 2009—10 influenza season-a multicentre, randomised controlled trial. Zoltan Vajo, Ferenc Tamas, Laszlo Sinka and Istvan Jankovics. Correspondence to Dr. Zoltan Vajo: [email protected]

Category: B. Blood/Immune Mechanisms. Keywords: safety, immunogenicity, H1N1 vaccine, seasonal influenza vaccine, multicentre randomised controlled trial
Synopsis edited by Dr Stephen Wilkinson, Melbourne, Australia. Posted on Global Family Doctor 13 January 2010

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