AN INTERNATIONAL network of laboratories, coupled with a multifaceted surveillance program in the United States, is helping the CDC anticipate next year's dominant influenza virus strains in time for pharmaceutical firms to make an effective vaccine.
The pharmaceutical companies' lengthy vaccine-manufacturing process mandates that researchers decide which strains should be included in the following year's vaccine while the nation still is in the midst of the current year's flu season.
By mid-February, experts from the CDC and Food and Drug Administration provide their data to the Food and Drug Administration's vaccine advisory panel that makes the final recommendations for the US vaccine. The World Health Organization (WHO), an autonomous unit within the United Nations system with headquarters in Geneva, Switzerland, usually echoes these recommendations, based on CDC data as well as data collected by Mill Hill in London, the other WHO influenza collaborating center.
Although the recommendations still harbor an