Investigating the association between influenza vaccination and reduced stroke risk.

Acute infections, mainly of the respiratory tract, have consistently been demonstrated to considerably increase the risk of stroke. At present, prospective interventional trials are lacking and there is no proof of the effectiveness of any therapeutic anti-infective strategy in stroke prevention. However, some new evidence from observational studies lends support to the idea that influenza vaccination may contribute importantly to fighting stroke. Although final proof of efficacy is still missing, patients with previous cerebral ischemia and subjects of any age at high risk of stroke should be encouraged to receive annual influenza vaccination.