The Human Papillomavirus Vaccine (HPV) Will Save Millions of Lives
We are usually in the dark when it comes to knowing what causes specific types of cancer. We may know about risk factors that increase the likelihood of some cancers, like cigarette smoking and lung cancer or alcohol consumption and liver cancer, but exactly how those risk factors work to make cells of a particular organ start to divide uncontrollably, is generally still a mystery.
An exception to this is the case of cancer of the female cervix. We know the cause of about 90% of cases of cervical cancer—the human papillomavirus (HPV). HPV is actually a group of about 200 viruses, only a few subtypes of which cause cancer. HPV is a sexually transmitted virus and virtually all sexually active people in the U.S. are infected with HPV.
HPV infects the cells called squamous cells that line the surface of several organs in the body. The immune system keeps most HPV infections in check, but some long-lived HPV infections have the ability to transform squamous cells into cancerous cells.
HPV Vaccine Prevents Most Cervical Cancer Cases
Vaccinating against HPV consequently prevents almost all cases of cervical cancers and is now recommended for all teenage boys and girls. Imagine that: we can actually tell people that a couple of HPV shots will virtually eliminate the risk of an entire type of cancer. A single HPV vaccine called Gardasil 9 is available in the U.S. The U.S. Centers for Disease Control and Prevention (CDC) recommends that all boys and girls aged 11-12 receive two doses of Gardasil 9, although the vaccine can be given to people up to 45-years-old. The second dose is given 6 to 12 months after the first. A three-dose regimen is recommended for people who get their first dose after age 15.
The World Health Organization (WHO) announced a program in 2020 that would drastically reduce the incidence of cervical cancer by, among other steps, vaccinating 90% of all girls by age 15. It is estimated that, if successful, such an initiative would prevent 8.7 million cases of cervical cancer among women born between 2005 and 2014. Women in Africa and Asia would realize the greatest benefit.
It is thus extremely difficult for us to understand why rates of HPV vaccine hesitancy seem to be increasing in the United States. In a study published earlier this year, investigators found that the rate of HPV vaccine hesitancy had risen from 50.4% of parents of vaccine-eligible children in 2012 to 64% in 2018. The authors speculated that misinformation about the HPV vaccine might be responsible for this increase in vaccine hesitancy.
The social media platform Pinterest decided in 2019 to moderate posts about HPV vaccine and a study published last year showed that while this had the effect of decreasing misinformation it also resulted in an overall decrease in posts about the vaccine. Thus, improving the quality of information about HPV vaccine on Pinterest had the unintended consequence of reducing the total amount of information available. All of this comes in the context of a general decrease in support for vaccines among parents in the U.S.
HPV Vaccine is Safe and Effective
There appear to be unfounded concerns about the safety of the HPV vaccine. A study published in June showed that safety concerns about the HPV vaccine increased substantially between 2008 and 2019. The authors noted that “The COVID-19 pandemic has brought to the forefront the fragility of public confidence in the safety of vaccines,” which raises the possibility that such safety concerns actually increased even more dramatically in the past year.
The HPV vaccine is clearly safe. Minor adverse reactions like fever or nausea and pain and swelling at the injection site are transient. More serious side effects are extremely rare. Anti-vaccination activists exploit the surveillance system called VAERS that CDC and the U.S. Food and Drug Administration (FDA) use to detect adverse side effects to vaccines. Anyone can report anything that happens after a person receives a vaccination to VAERS and health authorities will investigate. The adverse event is almost always a coincidence, but anti-vaccination activists relish advertising what gets reported to VAERS as if every event is proven vaccine related. It is important to emphasize once again that this is not the case; most things reported to VAERS turn out not to be vaccine related. Gardasil 9 has an excellent safety record. HPV vaccination does not make teenagers become more sexually promiscuous.
What it does do is prevent people from getting several types of cancer. The incidence of human papillomavirus infections has been reduced dramatically since the introduction of the vaccine. HPV vaccine similarly dramatically reduces the rate of cervical cancer. It also prevents, vulvar, vaginal, anal, penile, and some head and neck cancers. HPV vaccine is also credited with a reduction in premature births.
Still, more than a decade after the HPV vaccine was first introduced in 2006, only about half (51.1%) of U.S. adolescent women had completed the HPV vaccine series. By 2019 that number had risen only slightly to 56.8% of girls; the rate for boys was even lower (51.8%). States that mandate HPV vaccine for children not unexpectedly have higher vaccination rates, as do states with higher availability of pediatricians.
Preventing cancer is very difficult. Usually, to even have a shot at doing so people need to affect difficult changes in behavior, like quitting smoking, reducing alcohol consumption, and getting more exercise. Even doing those things is hardly guaranteed to work.
Then there is the case of cancer of the cervix. Two shots when a person is 11 or 12 years old reduces the risk to close to zero, and it does so with virtually no risk because in reality adverse side effects are almost all mild and transient. This seems like something every parent should want for their child.
We find it shocking, therefore, that only about half of the U.S.’ boys and girls have had the full HPV vaccination series and that hesitancy among parents to get their children vaccinated is growing, mostly because of misplaced safety concerns. What is going on here?
Insurance, both commercial and public, covers most people for HPV vaccine. Hence, financial access does not seem to be the issue. The finding noted above that vaccination rates are higher in states where there are more pediatricians suggests that there may be an awareness problem. Studies have shown that there are a variety of cost-effective programs like localizing vaccination sites in schools that work to improve HPV vaccine uptake. Renewed efforts to make parents aware of the need to have their children vaccinated against HPV are clearly needed.
There are two aspects of this problem that we find especially disturbing. We noted above that, as expected, states that have HPV vaccine mandates have higher vaccination rates. Why don’t all states have mandates? Apparently, issues of parents’ rights to refuse and the morality of vaccinating against a sexually transmitted disease come up in state legislatures when HPV vaccine mandates are discussed. While we of course respect everyone’s right to hold personal moral and religious views, there does not seem to be anything ethically appropriate about withholding an intervention with almost no risk that prevents a deadly disease. Should parents have the right to make a decision like that for their children, any more than we give parents the right to decide it is okay for their children to engage in life threatening activities like cigarette smoking and riding in cars without a car seat?
The second aspect that disturbs us involves the safety concerns. We believe that these are being trumped up by the well-organized anti-vaccination activist lobby and that this poses a direct threat to the public’s health. HPV vaccination saves lives and therefore it is especially morally pernicious to withhold it from someone who lacks legal decision-making capacity—i.e., minor children—and it is unethical to allow misinformation and disinformation about imaginary risks to go unchecked to the point that they influence the decision to vaccinate a child.
We do not believe merely wringing our hands is a sufficient response to low HPV vaccination rates in the U.S. or anywhere in the world. We insist that there is both a medical/scientific and a moral issue here. The medical/scientific issue is that HPV vaccination is a safe and effective method for preventing cervical and several types of cancer. The moral issue is that we are wrong to withhold a potentially lifesaving and nearly risk-free intervention from minor children. Stronger efforts should be made to increase vaccination rates against HPV among children.
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