What are the side effects of the HPV vaccine?

The human papillomavirus (HPV) is a sexually transmitted infection that affects about 14 million people every year.¹ If the virus does not resolve on its own, it can cause several different cancers including cervical and penile, as well as head and neck cancer in both men and women.² There are many different types of HPV that cause these cancers, and the most current vaccine, the 9-valent HPV vaccine, protects against nine different high-risk types of HPV.³

Over 100 million people have received the HPV vaccine in the U.S., and about 28 million people have received the 9-valent HPV vaccine since its FDA approval in 2014.⁴ All three HPV vaccines that have been available in the U.S. have been shown to be safe and effective by the Food and Drug Administration (FDA).⁵ The clinical trials for the 9-valent HPV vaccine enrolled 15,000 individuals. These patients have been monitored for over 15 years, demonstrating the vaccine’s overall safety.^5,6 Many independent studies have also shown that there have not been significant changes in the reported adverse events since the FDA approved the 9-valent HPV vaccine.^3,7  Once a vaccine, like the HPV vaccine, is available to the general public, it is tracked by the Vaccine Adverse Event Reporting System (VAERS). This is a national system that tracks possible safety problems in U.S.-licensed vaccines based on patient reporting of adverse reactions.

The most common side effects of the HPV vaccine are related to getting the injection.¹ Mild pain at the injection site is the most common side effect, reported by 63% to 90% patients.⁶ Other side effects at the injection site include swelling in 20% to 48% of people and redness in 17% to 34% of people. Severe forms of any of these injection-related side effects are rare, occurring for only 3% of participants in clinical trials. Muscle pain, joint pain, or nausea may also occur after the vaccine in some people but these side effects are less common.⁵  All these side effects normally resolve on their own in a few days.⁶

Headache is the most common systemic adverse reaction. Approximately 15% of patients may experience headaches.^1,6 Fever is another possible, but less common, systemic side effect which occurs in up to 5% of people.⁶ The vaccine may cause syncope in some but this is largely mitigated by the 15-minute observation period after receiving the HPV vaccine. Serious adverse events related to the vaccine, which include allergic reactions or asthmatic crisis, are extremely rare.

People with a moderate or severe acute illness should wait until after the illness resolves before getting the HPV vaccine.⁸ Many studies that included pregnant women have shown that the vaccine does not cause harm to the fetus or the mother. However, the HPV vaccine is still not recommended for women who are pregnant.⁹ Also, the HPV vaccine does not impact future fertility in women who plan on getting pregnant later in life.¹⁰

References

1. Markowitz LE, Dunne EF, Saraiya M, et al. Human papillomavirus vaccination: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 2014; 63 (Rr-05): 1-30.
2. Braaten KP, Laufer MR. Human papillomavirus (HPV), HPV-related disease, and the HPV vaccine. Rev Obstet Gynecol 2008; 1 (1): 2-10.
3. Donahue JG, Kieke BA, Lewis EM, et al. Near real-time surveillance to assess the safety of the 9-valent human papillomavirus vaccine. Pediatrics 2019; 144 (6).
4. Centers for Disease Control and Prevention. Questions about HPV Vaccine Safety. 2020; https://www.cdc.gov/vaccinesafety/vaccines/hpv/hpv-safety-faqs.html. Accessed 5 Dec 2021.
5. Centers for Disease Control and Prevention. HPV Vaccine Safety. 2021; https://www.cdc.gov/vaccinesafety/vaccines/hpv/hpv-safety-faqs. Accessed 5 Dec 2021.
6. GARDASlL 9 Vaccine [package insert]. Whitehouse Station, NJ: Merck Sharp & Dohme Corp.; 2021.
7. Shimabukuro TT, Su JR, Marquez PL, et al. Safety of the 9-valent human papillomavirus vaccine. Pediatrics 2019; 144 (6).
8. Kroger A, Bahta L, Hunter P. General Best Practice Guidelines for Immunization. Best Practices Guidance of the Advisory Committee on Immunization Practices (ACIP). 2021.
9. Landazabal CS, Moro PL, Lewis P, et al. Safety of 9-valent human papillomavirus vaccine administration among pregnant women: Adverse event reports in the Vaccine Adverse Event Reporting System (VAERS), 2014-2017. Vaccine 2019; 37 (9): 1229-1234.
10. Schmuhl NB, Mooney KE, Zhang X, et al. No association between HPV vaccination and infertility in U.S. females 18-33 years old. Vaccine 2020; 38 (24): 4038-4043.