Postlicensure surveillance of human papillomavirus vaccine using the Vaccine Adverse Event Reporting System, 2006-2017.

Background: The United States Food and Drug Administration (FDA) has licensed three HPV (Human papilloma virus) vaccines. The centers for disease control and prevention (CDC) and advisory committee on immunization practices (ACIP) recommends routine HPV vaccination at age 11 or 12 years. This study aimed to summarize and characterize adverse events following HPV vaccination reported to VAERS database from July 2006 to May 2017.

Methods: A systematic data mining was performed in the VAERS database for reports associated with HPV vaccine. Clinically relevant Vaccine Event Combinations (VEC) were identified in the VAERS database following HPV vaccination. A VEC was considered for analysis only if a minimum of hundred reports were present in database for the given Adverse Event (AE). The data mining algorithm used in this study was reporting odds ratio. A value of ROR-1.96SE >1 was considered as positive signal.

Results: VAERS received 49444 reports after receipt of HPV vaccine during the study period. Out of 49444, 2307 unique reactions were identified. A total of 177 death reports and 3526 non death serious reactions were reported to VAERS. ROR showed positive signals for abdominal pain, syncope, dizziness, convulsion, abortion spontaneous, alopecia, amenorrhea, anogenital warts, cervical dysplasia, anaemia, dyskinesia, migrane, blood pressure decreased, fall, head injury, loss of consciousness, pallor, presyncope, seizures.

Conclusion: The present analysis did not identify any new/unexpected safety concern and was consistent with the safety data from prelicensure trials. Further epidemiological studies are required to systematically validate the data provided by VAERS.