The advantages of giving elderly people the flu vaccine have been greatly exaggerated, according to the October edition of Lancet Infectious Diseases.

A team led by Lone Simonsen, MD, George Washington University, Washington, DC, says that vaccinating not-so-frail elderly people more frequently than their frail peers, plus the use of nonspecific endpoints, such as all-cause mortality, are the reasons for this exaggeration.

While tests have proven that the vaccine works in a younger population, some of the tests never included the elderly, in particular, those over 70—a crucial omission in light of three quarters of all flu deaths occur in seniors 70 and older. This suggests vaccine benefits in the elderly fall after the age of 70.

Surprisingly, coverage rose in this group from 15% in 1980 to 65% today, yet there has been no corresponding reduction in the number of deaths in this 27-year period.

Subsequent trials ought to take into account vaccine effectiveness against the highly specific outcome of laboratory-confirmed influenza virus, the team said. Despite effort and cost, the vaccine efficacy estimates have greater dependability. In addition, the epidemic period should be identified for each season by means of virus surveillance data.

The team was quick to add that the elderly are advised to continue with the vaccinations since some prophylactic measures are better than none, however, the effectiveness of vaccines in certain elderly populations needs to be more carefully studied before being published.