Increased risk of noninfluenza respiratory virus infections associated with receipt of inactivated influenza vaccine.
Clin Infect Dis. 2012 Jun ;54(12):1778-83. Epub 2012 Mar 15. PMID: 22423139
Benjamin J Cowling
We randomized 115 children to trivalent inactivated influenza vaccine (TIV) or placebo. Over the following 9 months, TIV recipients had an increased risk of virologically-confirmed non-influenza infections (relative risk: 4.40; 95% confidence interval: 1.31-14.8). Being protected against influenza, TIV recipients may lack temporary non-specific immunity that protected against other respiratory viruses.