World Health organization - It is recommended that vaccines to be used in the 2003/2004 Winter season contain the following strains:

• an A/New Caledonia/20/99 (H1N1)-like strain

• an A/Moscow/10/99/(H3N2)-like strain (A widely-used strain is A/Panama/2007/99)

• a B/Hong Kong/330/2001-like strain (Currently used vaccine strains include: B/Shandong/7/97, B/Hong Kong/330/2001 or B/Hong Kong/1434/2002)

As in previous years, the national control authorities should approve the specific vaccine viruses used in each country. National public health authorities are responsible for recommendations regarding the use of the vaccine.

Most of the population is likely to have been infected with influenza A(H1N1), influenza A (H3N2) and influenza B viruses. As a consequence, one dose of inactivated influenza vaccine should be immunogenic for individuals of all ages except young children. Previously unimmunized children should receive two doses of vaccine with an interval of at least four weeks between doses.

European Union - The Ad Hoc Influenza Working Group of the Committee for Proprietary Medicinal products (CPMP) was convened to select virus strains for the manufacture of influenza vaccines for the 2003/2004 season and has agreed that the WHO recommendations should be followed.

On the basis of cross reactivity and growth in eggs, the group agreed that for the purpose of vaccine manufacture the following strains be accepted:

• Reassortant virus RESVIR-17, which has beenderived from A/Panam/2007/99 as an A/Moscow/10/99-like strain

• Reassortant virus IVR-116 which is derived from A/New Caledonia/20/99 as an A/New Caledonia/20/99-like strain

• B/Shandong/7/97, which is a B/Hong Kong/330/2001-like strain.

References

1. Weekly Epidemiological Record, 78: 58 and 77 (2003).

2. European Agency for the Evaluation of Medicinal Products. Committee for Proprietary Medicinal products (CPMP) final EU recommendations for the influenza vaccine composition for the season 2003/2004. EMEA/CPMP/BWP/6011/03.19 March 2003.