A new peer-reviewed study has shown that the HPV vaccine has benefits for not only younger adults but also for middle-aged individuals. This is important to know since the HPV vaccine is one of the best ways to prevent cancer.
Let’s take a look at the HPV vaccine and this new paper.
What is HPV?
Genital and oral human papillomavirus (HPV) infections are the most common sexually transmitted infections (STI) in the USA. HPV is generally transmitted from personal contact during vaginal, anal, or oral sex.
It’s important to note that there are more than 150 strains or subtypes of HPV that can infect humans – however, only 40 of these strains are linked to one or more different cancers. Of those 40 strains, most are fairly rare.
Although the early symptoms of HPV infections aren’t serious and many HPV infections resolve themselves without long-term harm, a significant portion of HPV infections is causally linked to many types of cancers in men and women. According to current medical research, here are some of the cancers that are linked to HPV:
In addition, there is some evidence that HPV infections are causally linked to skin and prostate cancers. The link to skin cancer is still preliminary, but there is much stronger evidence that HPV is linked to many prostate cancers.
HPV is believed to cause nearly 5% of all new cancers worldwide, making it almost as dangerous as tobacco in that respect. According to the CDC, roughly 79 million Americans are infected with HPV – approximately 14 million Americans contract a new HPV every year. Most individuals don’t even know they have the infection until the onset of cancer. The CDC also states that over 46,000 HPV-related cancers are diagnosed in the USA every year. It may be several times that amount worldwide.
Let’s look at this another way — if we could stop HPV infections completely today, we would probably reduce the incidence of many forms of cancer by over 46,000. That would make a significant reduction in the 1.9 million new cases of cancer in the USA in 2022. And the problem is much more than this — as opposed to most other cancers, the incidence of HPV-related cancers is rising quite rapidly. And the rate of HPV vaccination has dropped significantly during the COVID-19 pandemic.
HPV vaccines
There were two HPV vaccines on the world market before 2014. GSK, also known as GlaxoSmithKline, produced Cervarix, a bivalent (protects against two HPV strains) vaccine. It has been withdrawn from the US market (although available in many other markets), because of the competition from the quadrivalent (immunizes against four different HPV strains) and 9-valent (against nine HPV strains) Gardasil vaccines.
Merck manufactures Gardasil, probably the most popular HPV vaccine in the world. The first version of the vaccine, quadrivalent Gardasil, targets the two HPV genotypes known to cause about 70% of cervical cancer and two other HPV genotypes that cause genital warts. In Europe and other markets, Gardasil is known as Silgard.
The newer Gardasil 9, approved by the FDA in 2014, is a 9-valent vaccine that protects against HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. It targets the four HPV strains found in the quadrivalent version, along with five additional ones that are linked to cervical and other HPV-related cancers. Both versions of Gardasil are prophylactic, meant to be given to females or males before they become exposed to possible HPV infection through intimate contact.
Gardasil is one of the easiest and best ways to prevent a few dangerous and, to abuse the definition slightly, common cancers that afflict men and women. Without a doubt, the HPV vaccine prevents cancer.
Currently, in the United States, the Advisory Committee on Immunization Practices (ACIP) recommends that preteen girls and boys aged 11 or 12 are vaccinated against HPV. The vaccine is also recommended for teenage girls and young women up to the age of 26 who did not receive it when they were younger, and teenage boys and young men up to the age of 21.
Some adults ages 27 through 45 years might decide to get the HPV vaccine if they did not get adequately vaccinated when they were younger. HPV vaccination of people in this age range provides less benefit, for several reasons, including that more people in this age range have already been exposed to HPV and have a lower immune response to the vaccine.
On the other hand, giving the HPV vaccine to younger children makes more sense. Their immune system is more robust, so when they receive the vaccine their immune system builds a longer-lasting immunity to the virus.
Let me sum this up so that if you come away from what I have with nothing else, you get this summary. HPV is a sexually transmitted disease. HPV causes 46,000 cancers a year in the USA alone. The HPV vaccine prevents becoming infected by HPV, which means you are protected from these cancers.
One last thing — the HPV vaccine is extraordinarily safe. And it is effective in preventing cancer.
The HPV vaccine for middle-aged adults paper
In a paper published on 11 January 2023 in Open Forum Infectious Diseases, Laura M King, MPH, Division of Epidemiology, School of Public Health, University of California Berkeley, and colleagues examined the effect of the HPV vaccine on middle-aged (mid-adults).
The researchers concluded that:
- The HPV vaccine is safe, efficacious, and likely to benefit both HPV-naïve middle-aged adults and those with previous infections.
- Universal mid-adult HPV vaccination in the U.S. could avert 20,934–37,856 cancer cases over 100 years, costing $141,000–$1,471,000 per quality-adjusted life-year gained.
The CDC’s Advisory Committee on Immunization Practices (ACIP) recommends that HPV vaccination in middle-aged adults be based on shared clinical decision-making (SCDM). SCDM is a process by which clinicians and patients work together to make a decision based on risks, benefits, and patient preferences for HPV vaccination.
The researchers concluded that:
Greater awareness among clinicians and mid-adult patients and broad implementation of SCDM may accelerate progress toward eliminating HPV-associated cancers and other diseases
Summary
Once again, we have data that the HPV vaccine is not only an important vaccine for young adults and teens, but it is also an important vaccine for middle-aged adults. Even though most mid-adults have probably been exposed to one or two strains of the human papillomavirus, they haven’t been exposed to all nine strains that are in the current vaccine.
We have a large body of evidence that shows that the vaccine prevents cancer in young adults, and it will do the same for these mid-adults.
If you are in your 30s or 40s, get the HPV vaccine. It might save your life.
Citations
- King LM, Lewnard JA, Niccolai LM. Clinical and Public Health Considerations for HPV Vaccination in Midadulthood: A Narrative Review. Open Forum Infect Dis. 2023 Jan 11;10(1):ofad004. doi: 10.1093/ofid/ofad004. PMID: 36726535; PMCID: PMC9887268.
- Meites E, Szilagyi PG, Chesson HW, Unger ER, Romero JR, Markowitz LE. Human Papillomavirus Vaccination for Adults: Updated Recommendations of the Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep. 2019 Aug 16;68(32):698-702. doi: 10.15585/mmwr.mm6832a3. PMID: 31415491; PMCID: PMC6818701.
