There are limited summary data published on the risk of fever and febrile seizures in children following influenza vaccination. We performed a review of the risk of fever and febrile seizures following receipt of trivalent inactivated influenza vaccine (TIV) in children aged ≥ 6 months to <36 months, searching PubMED and Google Scholar for English language articles from 2000 onwards, and initiated or ongoing unpublished studies since September 2007 using clinicaltrials.gov. Exclusions included other vaccine co-administration, missing ages or participant numbers, or unmeasured fever. We reviewed articles and collated results using a standard data extraction template.We identified a total of 909 published papers and unpublished trials from a search conducted on 23 January 2013, 669 from Google Scholar, 114 from PubMed and 126 from the Clinicaltrials.gov online database. After excluding 890 published papers or unpublished trials, 5 published papers and 14 unpublished trials were included in this review. Extracted data on number of events, children at risk and time of follow-up were converted to the risk of fever, which was averaged per week of follow-up (referred to as 'averaged weekly risk').Following one dose of TIV, the median averaged weekly risk of any fever ( ≥ 37.5. °C) was 26.0% (range 10.3-70.0%) in unpublished trials compared to 8.2% (range 5.3-28.3%) in published papers ( p = 0.04). The median averaged weekly risk of severe fever ( ≥ 39.0. °C) was 3.2% (range 0-10.0%) and 2.0% (range 0.6-17.0%), respectively ( p = 0.91).Variation in the reporting of fever by participant age groups, time since vaccination and the definition or measurement of fever resulted in a wide range of risk estimates. Reporting of febrile reactions should be standardised to allow comparison between manufacturers and influenza seasons. © 2013 Elsevier Ltd.
- Newborn
- Children
- Influenza
- Safety
- Administration
