HPV vaccination: An analysis of VAERS adverse event reports

Purpose: Describe the frequency and type of adverse events reported following HPV vaccination with Gardasil® compared to the meningococcal conjugate vaccine, Menactra®, which has a similar target population. Methods: We included Vaccine Adverse Event Reporting System (VAERS) reports from 6/8/06-12/8/08 for Gardasil® and from 1/14/05-7/14/07for Menactra® (i.e. 2.5 years after initial FDA approval). Analyses were restricted to females within the recommended age range of each vaccination (i.e. 11-26 and 11-18, respectively). Descriptive statistics were used to summarize the data related to both vaccines.Results: 8,666 Gardasil® and 735 Menactra® reports were filed with VAERS. The average number of symptoms per report was 4.3 for both vaccines. Most Gardasil® reports (75%) followed injection with a single vaccine (range 1-8). Menactra® reports were frequently in combination with other vaccines. 22 deaths and 133 life-threatening illnesses were reported for Gardasil®; 0 deaths and 10 life-threatening illnesses for Menactra®. A visit to the ER or physician was reported on 4,502 occasions for Gardasil® and 313 for Menactra®. Hospitalization was reported on 409 and 53 occasions, and disability was reported on 235 and 4 occasions, respectively. 54% of individuals with Gardasil® events and 67% with Menactra® events reported recovery.Conclusions: VAERS data indicate that 7.3% of Gardasil® reports and 8.2% of Menactra® reports were serious. Gardasil® is one of the most studied vaccines ever produced, and its efficacy is well established. Provider and consumer education concerning the true risks associated with this vaccine are of utmost importance in the dissemination of this cancer prevention tool.