HPV vaccines do far more than prevent cervical cancer in women, according to new research that's reshaping how doctors think about protecting both sexes. Men and boys who received the HPV vaccine between ages nine and 26 were nearly 50% less likely to develop cancers of the head and neck, esophagus, anus, or penis, according to a study published in JAMA Oncology and involving more than 510,000 vaccinated males compared with an equal number of unvaccinated men .

The findings arrive two decades after the first HPV vaccine was approved, yet many people still associate the shot exclusively with preventing cervical cancer in women. The new evidence suggests that perception has limited our understanding of one of modern medicine's most powerful cancer-prevention tools.

What Cancers Does HPV Actually Cause?

Human papillomavirus is far more common than most people realize. More than 42 million Americans are currently infected with types of HPV known to cause disease, and about 13 million Americans, including teens, become newly infected each year through sexual contact . In most cases, the immune system clears the virus on its own. But about 1% of people develop chronic infections that dramatically increase cancer risk.

HPV causes more than 90% of cervical cancers, but that's only part of the story. The virus is responsible for most cancers of the vagina, vulva, penis, and anus, as well as a growing number of head and neck cancers . These other cancers often go undetected until they cause symptoms like pain or swelling, meaning they're typically found at a more advanced stage when treatment is harder and outcomes are worse.

The new study examined vaccinated and unvaccinated men using a nine-strain HPV vaccine, which together prevent 90% of cervical cancers and protect against the strains most likely to cause other malignancies .

Why This Study Changes the Conversation About HPV Vaccines

The research is significant because it provides the strongest evidence to date that HPV vaccines protect men as well as women. When the first HPV vaccine was approved in 2006, it was recommended only for girls to prevent cervical cancer and genital warts. The FDA approved the shots for boys in 2009, but they weren't broadly rolled out for males until 2012, after an official CDC recommendation . That delay meant millions of boys missed the window for protection during their most vulnerable years.

"This is a vaccine that is preventing cancer in a major way," said Oliver Brooks, MD, a pediatrician and spokesman for the National Foundation for Infectious Diseases.

Oliver Brooks, MD, Pediatrician and Spokesman for the National Foundation for Infectious Diseases

The study's size and scope make it particularly compelling. Researchers tracked more than 510,000 boys and men vaccinated between January 2016 and December 2024, comparing them with an equal number of unvaccinated males . That scale provides strong statistical power to detect real differences in cancer risk.

How HPV Vaccines Work to Prevent These Cancers

Understanding the mechanism helps explain why the vaccine is so effective across multiple cancer types. HPV vaccines work by training the immune system to recognize and fight specific strains of the virus before infection occurs. The vaccines contain proteins that mimic the surface of HPV, triggering an immune response without causing infection. When vaccinated people encounter the actual virus later, their immune system is primed to neutralize it before it can establish a chronic infection.

Because the same HPV strains cause multiple types of cancer, protecting against the virus protects against all of them simultaneously. The nine-strain vaccine used in the study covers the HPV types responsible for approximately 90% of cervical cancers and the vast majority of other HPV-related malignancies .

Steps to Ensure Your Family Gets HPV Protection

• Timing Matters: The CDC recommends HPV vaccination at ages 11 to 12, when the immune response is strongest and before most people become sexually active. However, vaccination is approved for anyone ages 9 to 45, so it's never too late to ask your doctor about eligibility .
• Both Boys and Girls Need Protection: HPV vaccines are recommended for all children and teens, regardless of sex. The new study underscores that boys benefit just as much as girls, yet vaccination rates remain lower in males. Parents should ensure both sons and daughters receive the full series .
• Complete the Series: HPV vaccines require multiple doses for full protection. Ask your healthcare provider about the recommended schedule and ensure all doses are completed, as incomplete vaccination leaves gaps in protection .

Why Awareness Remains a Major Barrier

Despite two decades of vaccine availability and mounting evidence of benefit, awareness remains surprisingly low. A survey published in JAMA Oncology found that more than one-third of US adults are unfamiliar with HPV itself, and more than 70% were unaware that HPV causes oral cancers . Many people who answered the survey were also unaware that an HPV vaccine exists.

This knowledge gap has real consequences. HPV vaccination coverage among US teens remained unchanged from 2022 to 2024, with 78.2% receiving at least one dose and only 62.9% completing the full recommended series . That means roughly one in four teens are missing protection against cancers that could be prevented entirely.

"Children, adolescents, parents and health care workers should be more informed about the expected benefits of HPV vaccine, not just cervical cancer," said Taito Kitano, DrPH, first author of the study and a researcher at Nara Prefecture General Medical Center in Nara, Japan.

Taito Kitano, DrPH, Researcher at Nara Prefecture General Medical Center

Misinformation has also played a role in dampening uptake. Some public health officials have made unfounded claims about HPV vaccine safety, despite an abundance of data showing the shots to be remarkably effective and safe . These claims have created confusion among parents and delayed vaccination decisions.

What the Evidence Shows About Safety and Long-Term Protection

The safety profile of HPV vaccines is well-established. More than 300 million doses have been administered worldwide over the past two decades, providing extensive real-world data on safety . Serious adverse events are extremely rare, and the vaccines have been studied in large clinical trials before approval and monitored continuously afterward.

Regarding duration of protection, scientists continue to gather data. A study published in December found that HPV vaccines prevent precancers of the vagina and vulva, extending the list of conditions the vaccine protects against . Two recent studies suggest that HPV vaccines have created herd immunity, meaning vaccination rates high enough to lower virus levels in the population and protect even unvaccinated people .

Another study published last year suggested that a single shot may provide as much protection for girls as a two-dose regimen, though some scientists say more research is needed to understand the duration of protection for both boys and girls before changing vaccination recommendations .

The bottom line is clear: HPV vaccines represent one of the most effective cancer-prevention tools available. As evidence accumulates showing benefits beyond cervical cancer, experts say it's time for a broader conversation about protecting all young people against a virus that causes multiple types of cancer.