The success of the COVID-19 vaccine, an almost unthinkable scientific feat just a year ago, has once again brought the debate about required immunization to our state’s attention.

While states and districts decide whether children should have to receive the COVID-19 vaccine before returning to the classroom, it is a good time to remember another lifesaving vaccine that is grossly underutilized and should also be mandated by Pennsylvania schools: the HPV vaccine.

HPV, or human papillomavirus, causes a variety of ailments ranging from benign to deadly. Some strains cause genital warts, while others cause cancers of the cervix and other organs. It is spread through any kind of genital contact and is so common that the vast majority of Americans will be infected with some strain during their lifetime.

First approved for girls in the United States in 2006, the HPV vaccine is one of two available vaccines that prevent cancer-causing viruses. Since its debut, it has proven so safe and effective that the American Academy of Pediatrics now recommends the two-shot series for all children beginning at age 9.

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Despite this recommendation, the HPV vaccine is administered at drastically lower rates than other childhood immunizations. In 2019, according to the Centers for Disease Control and Prevention, only 51% of teens were up-to-date on their HPV series, compared with 91% for the measles-mumps-rubella series.

When the vaccine was first introduced, vaccination was hindered by a belief that getting the shot would encourage teenagers to have sex. There is ample evidence to disprove this theory, and fortunately, this now falls relatively low on the list of reasons why parents choose not to vaccinate their children.

But based on the gaping divide in vaccination rates, it is indisputable that parents still view the HPV vaccine as different from other childhood vaccinations.

Allowing parents to continue to refuse or delay vaccination based on these views carries deadly consequences. The need for mandated HPV vaccination is not about sex at all — it’s about cancer.

Cervical cancer is one of the leading causes of cancer deaths in women worldwide. Treatment of advanced cervical cancer often requires disfiguring pelvic surgery, chemotherapy, and radiation. Despite this aggressive treatment, advanced cervical cancer carries a dismal 17% five-year survival rate.

And although cancer is the most dreaded outcome of HPV infection, it is by no means the only unpleasant one. HPV-infected people with positive Pap tests must undergo colposcopy and biopsy, an uncomfortable procedure that involves removing a piece of the cervix for microscopic examination. If that biopsy shows cancer or precancer, that patient is now subject to further removal of portions of the cervix (or even its entirety), which can carry complications including bleeding, damage to other organs, infection, and preterm birth.

These outcomes — not to mention those of the other cancers that HPV causes — will be the fate of thousands of children whose parents refuse to have them vaccinated. According to the CDC, using the vaccine as recommended could prevent over 32,000 HPV-related cancers each year.

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As a pediatrician, I and my colleagues have developed strategies to encourage HPV vaccination. These include focusing on the cancer-causing aspect of HPV rather than the sexually transmitted one, emphasizing the robust data supporting its safety, and grouping it with the other recommended vaccines rather than discussing it separately.

While education campaigns and one-on-one discussions are critical for building community buy-in, at best they are modestly effective. The best tool we have for increasing HPV vaccination and preventing cancer is to mandate it for school attendance. Doing so will be an education campaign in itself: It will signal that the HPV vaccine is just as critical to children’s health as those for meningitis and chicken pox.

Some parents decline to vaccinate on time because of a desire to wait until their children are older. Unfortunately, delayed vaccination carries risk. The shot is most effective when it is given prior to the onset of any kind of sexual activity. Since over half of American teenagers have been sexually active by the time they turn 18, and we don’t test for HPV until age 21, allowing parents to wait until they decide their children are old enough to talk about sex is not only unnecessary — it wastes critical time.

Besides, there is another vaccine against a sexually transmitted, cancer-causing virus that Pennsylvania’s public schools require for attendance: the hepatitis B vaccine given to infants.

Three states have already mandated HPV vaccination for schools, and the results have been encouraging. Rhode Island began requiring HPV vaccination for enrollment in seventh grade in 2015 and since then has made significant headway closing the gap between HPV and other required vaccinations.

By allowing half of our nation’s children to go unvaccinated against HPV, we are dooming tens of thousands of them to grow up into cancer patients. They will undergo painful treatments and psychological trauma, and many will die. We have a safe and effective way to save them from this fate. We owe it to them to make sure they receive it.

Leigh Finnegan is a resident physician in pediatrics in Philadelphia.