Data On Flu Vaccine's Effectiveness Questioned
Amid gap between policy and evidence, a call for re-evaluation
FRIDAY, Oct. 27 (HealthDay News) -- Although public policy worldwide advises using inactivated influenza vaccine against seasonal flu outbreaks, systematic reviews show that the flu vaccine's performance is questionable, according to a report published in the Oct. 28 issue of BMJ.
Tom Jefferson, M.D., of the Cochrane Vaccines Field in Rome, Italy, writes that each year, vast resources go into identifying circulating flu viruses, developing matching vaccine and delivering it to the most susceptible sections of the population.
But after analyzing decades of systematic reviews of studies involving the flu vaccine, Jefferson found that many original studies are poor-quality and may exaggerate the benefits of inactivated flu vaccines.
Overall, Jefferson found a lack of reliable case-control studies of the flu vaccine's effectiveness or safety. The researcher found only five randomized studies reporting adverse effects among the elderly; insufficient data considering the widespread annual administration of vaccine in the elderly. With the current surveillance system unable to distinguish between influenza and influenza-like illness, better surveillance procedures are also needed.
"Reasons for the current gap between policy and evidence are unclear, but given the huge resources involved, a re-evaluation should be urgently undertaken," the researcher writes.