Recommendations for Influenza Vaccine Composition

Northern hemisphere: November 1999 to April 2000

This recommendation relates to the composition of vaccines for the forthcoming winter in the northern hemisphere (November 1999 to April 2000). A second recommendation will be made in September 1999 which relates to vaccines that will be used for the winter in the southern hemisphere (May to October 2000). Epidemiological considerations will influence which recommendation (February or September) is more appropriate for countries in equatorial regions. Consequently, it is recommended that vaccines to be used in the 1999-2000 season contain the following:

  • an A/Sydney/5/97 (H3N2)-like virus
  • an A/Beijing/262/95 (H1N1)-like virus
  • a B/Beijing/184/93-like virus*


  • a B/Shangdong/7/97-like virus.

* The most widely used vaccine virus is B/Harbin/7/94.

(fromWeekly Epidemiological Record, Vol. 74, 8, 1999 )