Tuesday, February 26, 2008

Flu Vaccine Due for Major Changes – First Time Recommendation from Government Advisory Board

Predicting the flu is not all scientific. Well, it is, but only in part. This year, for instance,experts missed the mark. The strain of Influenza A that has dominated this winter has accounted for 60%of influenza cases and the vaccine provided by manufacturers was not a match.

Experts had a notion that this may occur, but they were unable to find samples of the strain that would grow properly, thwarting efforts to manufacture the right vaccine. Nancy Cox, PhD, head of the CDC's influenza division says "We simply came up empty-handed.”

Influenza vaccine targets three different strains of the H3N2, or Influenza A virus to provide a broad base of protection. Now experts are recommending that the vaccine receive a complete overhaul by replacing all three strains.

Determinations regarding which vaccines are needed each year are based on samples taken from the Far East where influenza normally starts. It is a guess as to whether the same strains will prevail, but most of the time the predictions are accurate. Obviously, that wasn’t the case this winter, causing concerns that the current flu vaccine is ineffective.

The challenge will be for manufacturers to get the vaccine out in time for next year’s flu season. They will have to grow and massively produce the vaccine fairly quickly, something that may be a bit unpredictable. For now, Norman Baylor, PhD, head of the office of vaccines research and review at the FDA says people should take the current vaccine “even though the strain is off”. Those with healthy immune systems are likely to respond well to available flu vaccine, but it may not be as effective for infants, those who are chronically ill or for elders.

Dr. Cox points out vaccine manufacturers will "have a jump on the situation" because recommendations were made September, 2007 regarding two of the three new vaccine strains.

Source: http://www.medscape.com/viewarticle/570672?sssdmh=dm1.337928&src=nldne