Hak and colleagues1 have performed a good case-control study, and the results are greatly in favor of influenza vaccination for persons at risk. However, their conclusion that influenza vaccination is also beneficial for persons at risk younger than 18 years is not convincing. The authors show a reduction of general practice visits among this age group, but these findings could not be confirmed in some recent randomized controlled trials.2,3 It is surprising that the authors only refer to older studies that have serious flaws, as reported before by one of us.4 Hak et al1 do not refer to the recent randomized controlled trial by Hoberman et al2 in which no effect was found of influenza vaccination on acute otitis media or utilization of selected health care and related resources.
Damoiseaux R, van der Wouden JC, Bueving H. Influenza Vaccination Effectiveness Is Not Proven in Younger Individuals at Risk. Arch Intern Med. 2005;165(16):1921-1922. doi:10.1001/archinte.165.16.1921