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The Use of Antivirals for Influenza Prophylaxis: A Review of the Clinical Effectiveness

Last updated: July 5, 2017
Project Number: RC0890-000
Product Line: Rapid Response
Research Type: Drug
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What is the clinical effectiveness regarding the use of antivirals for seasonal influenza?
  2. What is the clinical effectiveness regarding the use of antivirals for pandemic influenza?

Key Message

The evidence suggested that influenza prophylaxis with oseltamivir or zanamivir was effective in preventing symptomatic influenza at the individual and household levels, including healthy individuals of various ages exposed to seasonal or pandemic influenza.Both antivirals had no significant effect on asymptomatic influenza. Oseltamivir did not affect the number of hospitalizations. Zanamivir significantly reduced the risk of self-reported, investigator-mediated, unverified pneumonia in adults but not oseltamivir. At the community levels, influenza prophylaxis was associated with lower risk of influenza infection. Adverse effects of antiviral prophylaxis included psychiatric effects, headaches, and nausea. For the other neuraminidase inhibitors, laninamivir was effective in preventing the occurrence of influenza in a randomized controlled trial. For pandemic influenza prophylaxis, the evidence indicated oseltamivir and zanamivir are likely to be effective.