Flu vaccine estimates lower than originally estimated

Flu vaccine makers have started to release production estimates that show a somewhat lower total of vaccinations than was estimated last year.

Tom Skinner, a spokesman for the CDC, said that it projected the total number of doses for the 2012-2013 season is expected to range from 146 million to 149 million, CIDRAP News reports.

At this time last year, however, the early estimate was for between 166 million and 173 million doses.

The CDC's final flu vaccine report for the 2011-2012 season, which was released in early February, showed that companies distributed 132.1 million doses.

Because problems can arise at any point in the production cycle, flu vaccine production is incredibly unpredictable. A WHO advisory group recommended changing two of the three flu strains in the vaccine in February following two seasons that saw the three strains stay the same.

Flu makers report that production is going smoothly but some experts that the two strain change could cause problems with production, CIDRAP News reports.

This year's upcoming flu vaccination season follows a widely referenced meta-analysis that raised questions about the standard flu vaccine's effectiveness. The strict meta-analysis of high quality randomized controlled trials was published in the Lancet in October and put seasonal flu vaccine efficacy at 59 percent for adults under the age of 65. The commonly cited estimates were as high as 90 percent.