Vaccines for preventing influenza in healthy adults

."?>The preventive effect of parenteral inactivated influenza vaccine on healthy adults appears to be small and similar to live aerosol vaccines.

A Cochrane review included 90 reports; 69 were clinical trials of over 70 000 people, 27 were comparative cohort studies (about eight million people), and 20 were case-control studies (nearly 25,000 people)

The overall effectiveness of inactivated parenteral vaccine against influenza-like illness (ILI) is 16% (95% CI 5% to 25%), with a corresponding number needed to vaccinate (NNV) to prevent one ILI of 40 (95% CI 26 to 128). The effectiveness of live aerosol vaccines on healthy adults is similar to inactivated vaccines: 46 people (95% CI 29 to 115) would need immunisation to avoid one ILI case. The overall efficacy of inactivated vaccines in preventing influenza is 60% (95% CI 53% to 66%) with a NNV of 71 to prevent one case of influenza (95% CI 64 to 80). When vaccine content matches the circulating strain the efficacy is 62% (95% CI 52% to 69%) and the NNV is 58 (95% CI 52 to 69). Four trials evaluated time off work, estimating that vaccination saves on average around 0.04 working days equal to 17 minutes. The protection against ILI that is given by the administration of inactivated influenza vaccine to pregnant women is uncertain or at least very limited; the effect on their newborns is not statistically significant.

Comment: The quality of evidence is downgraded by study limitations

Ədəbiyyat

1. Jefferson T, Di Pietrantonj C, Rivetti A, Bawazeer GA, Al-Ansary LA, Ferroni E. Vaccines for preventing influenza in healthy adults. Cochrane Database Syst Rev 2010;(7):CD001269. .
2. Jefferson T, Di Pietrantonj C, Rivetti A et al. Vaccines for preventing influenza in healthy adults. Cochrane Database Syst Rev 2014;3():CD001269.