Source: The Lancet: Infectious Diseases, 2010 Nov 22. [Epub ahead of print]
Date of publication: November 2010
Publication Type: Journal Article
In a nutshell: Background: Few prospectively collected data are available to support the effectiveness of inactivated influenza vaccines in children younger than 2 years. We aimed to establish the effectiveness of trivalent inactivated influenza vaccine against laboratory-confirmed influenza A and B infections in a cohort of children younger than 3 years. Findings: We enrolled 631 children into our study with a mean age of 2·13 years (range 9—40 months). Seven (5%) of 154 fully vaccinated children and 61 (13%) of 456 unvaccinated children contracted influenza during the study (effectiveness 66%, 95% CI 29—84; p=0·003). In the subgroup of children younger than 2 years, four (4%) of 96 fully vaccinated children and 21 (12%) of 172 unvaccinated children contracted influenza (66%, 9—88, p=0·03). We were unable to record any adverse events associated with the vaccination of the children in our study. Interpretation: Trivalent inactivated influenza vaccine was effective in preventing influenza in young children, including those younger than 2 years. Our findings suggest that influenza vaccine recommendations should be reassessed in most countries.
Length of publication: Unknown