Flu vaccine’s effect is very modest concludes the Cochrane Collaboration

Posted by .(JavaScript must be enabled to view this email address)
Tuesday, March 08, 2016 1:22 pm Email this article

“Influenza vaccines have a very modest effect in reducing influenza symptoms and working days lost in the general population, including pregnant women,” concludes a review by the Cochrane Collaboration.

They note that “at least 40 people would need vaccination to avoid one [influenza-like illness] case… and 71 people would need vaccination to prevent one case of influenza. Vaccination shows no appreciable effect on working days lost or hospitalisation.”

They also note that “Over 200 viruses cause influenza and [influenza-like illness], producing the same symptoms (fever, headache, aches, pains, cough and runny noses). Without laboratory tests, doctors cannot distinguish between them as both last for days and rarely lead to death or serious illness. At best, vaccines may only be effective against influenza A and B, which represent about 10% of all circulating viruses.”

Their 2010 review on the same subject also noted that, “The review showed that reliable evidence on influenza vaccines is thin but there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies.”

The 2010 review also noted that, “There is no evidence that they affect complications, such as pneumonia, or transmission [of the flu to other people].”

References

Demicheli V JT, Al-Ansary LA, Ferroni E, Rivetti A, Di Pietrantonj C. Vaccines for preventing influenza in healthy adults (Review). The Cochrane Collaboration, 2014; http://www.cochrane.org/CD001269/ARI_vaccines-to-prevent-influenza-in-healthy-adultshttp://www.cochrane.org/CD001269/ARI_vaccines-to-prevent-influenza-in-healthy-adults

Jefferson T DPC, Rivetti A, Bawazeer GA, Al-Ansary LA, Ferroni E. Vaccines for preventing influenza in healthy adults (Review). The Cochrane Collaboration, 2010; Issue 7: http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD001269.pub4/full

 

Articles on the same subject can be found here:

• Influenza (Flu)

• Vaccines