When your kid is 11 or 12 years old, the sex talk — the one about the birds and the bees and using protection — might seem like a long way away. But it’s definitely not too early for the HPV vaccine. HPV, or human papillomavirus, is the most common sexually transmitted infection — around 80 percent of adults have been exposed to it at some point in their life. And it isn’t something to mess around with. Usually, the immune system completely clears the virus within a year or two, and most people won’t experience any symptoms. But out of the more than 100 strains of HPV, at least 14 have the potential to cause a range of cancers, most notably cervical cancer.
Cervical cancer is the fourth most common cancer among women, according to the National Institutes of Health. Good news: that means it’s almost completely preventable with two quick jabs of the HPV vaccine.
Fifteen years after the U.S. Food and Drug Administration’s (FDA) 2006 approval of the HPV vaccine, its impact on rates of cervical cancer is undeniable. For a recent study, published in JAMA Pediatrics, scientists compared cervical cancer rates in two different time periods: 2001-2005 (pre-vaccine) and 2010-2017 (post-vaccine). Among teens and young adults between the ages of 15 and 24, rates of cervical cancer dropped nearly 38 percent, and deaths dropped by 43 percent. Among adults between 30 and 39 years old, the change in diagnoses and deaths was much less substantial: an eight percent decrease in diagnoses and about a 39 percent decrease in deaths. The difference between the younger and older groups? The teens and young adults had the opportunity to get vaccinated against HPV; the older adults did not.
With the HPV vaccine, we essentially have a vaccine against cancer. But before making an appointment for the shot, you’ll likely have a bunch of questions: Are there any HPV vaccine side effects? Can it wait until my kid is older? Should boys get the vaccine? Here, we answer all your HPV vaccine questions.
At What Age Should Kids Get the HPV Vaccine?
The Centers for Disease Control and Prevention (CDC) recommends that all kids receive the HPV vaccine at 11 or 12 years old, or as early as 9 years old. That may seem young, but the age range is important for several reasons.
First, 11- and 12-year-olds have a stronger immune response to the vaccine than older teens. Their immune systems pump out more virus-fighting antibodies compared to older kids, according to the University of Utah Health. In fact, to achieve the immune response needed to protect against infection, kids younger than 15 only need two doses, but older teens need three shots. Tweens and teens younger than 15 need to wait at least six months between doses, while older teens need to wait 1-2 months before their second vaccine and another six months before their third.
There’s also the (sometimes uncomfortable) fact that during those tween years, puberty is just around the corner, if it hasn’t hit yet. It’s important that tweens and teens get vaccinated against HPV well before they start having sex. HPV is common enough that most adults pick it up soon after first becoming sexually active, according to the CDC. (HPV isn’t just passed via intercourse — it can also be contracted through oral sex and intimate touching.)
But getting the HPV vaccine doesn’t need to involve a conversation about sex. Instead, parents can simply explain to kids that the vaccine is protecting them against HPV infection and up to six types of cancer.
What Is the HPV Vaccine Age Limit?
Although it’s best to get vaccinated as a tween, it’s not too late for older teens and young adults. The CDC recommends the HPV vaccine for youth up to 26 years of age. After that point, experts say that the vaccine is no longer useful to most people, who likely will have been exposed to HPV. There are exceptions, however, for adults over 26 who have a lower chance of previous exposure — for example, if they haven’t yet become sexually active or have had only one monogamous sexual relationship.
Although it’s not ideal to get the vaccine after becoming sexually active, it’s still potentially worth it, depending on how many partners a person has had and those partners’ risk of exposure. Remember: the vaccine prevents nine cancer-causing strains of HPV. It’s possible to fight off one strain, then later be exposed to a second strain after having sex with a new partner. So even if a person is sexually active and has been exposed to HPV, the vaccine offers protection from other strains of the virus — and a better chance of avoiding cancer caused by HPV.
Are There Any HPV Vaccine Side Effects?
Prior to its approval, Gardasil 9, the HPV vaccine currently used in the U.S., went through 15 years of monitoring and research. It was studied in clinical trials with more than 29,000 people of all sexes and genders, according to the CDC. Since then, the CDC has continued to monitor side effects through the Vaccine Adverse Event Reporting System.
The most common side effects reported are redness and pain at the injection site, headache, fever, and fainting, which is an especially common reaction to vaccines in teens. Although these side effects may be uncomfortable, none are particularly harmful, and they’re all short-term.
What About HPV Vaccine Long-Term Side Effects?
The CDC has also investigated whether there is any relationship between the HPV vaccine and a number of long-term conditions, including auto-immune disorders, chronic fatigue syndrome, chronic pain, and premature menopause.
Early on, some scientists raised concerns about an association between the HPV vaccine and Guillain-Barré syndrome, an auto-immune disease which leads to nerve degeneration and neurological complications. However, these cases were rare, on the order of a handful out of tens of millions. Later, multiple large-scale studies found that Guillain-Barré syndrome, which can have a sudden onset, didn’t occur in vaccinated people more frequently than in the general public. A paper published in Science Reports suggesting a connection to neurological damage was later retracted due to problems with the study methods. In other words, any apparent association was likely due to random chance.
The story is the same with other long-term conditions. For instance, the CDC received reports of two physician-diagnosed cases of premature menopause in women who had received the HPV vaccine — out of 60 million doses administered. Upon further analysis, scientists found that premature menopause happens at a similar rate in unvaccinated people. Again: all signs point to random chance.
So there are no documented long-term side effects from the HPV vaccine, and it’s unlikely that any are going to pop up now, 15 years after approval of the vaccine.
Does the HPV Vaccine Affect Fertility?
Getting the HPV vaccine isn’t associated with any changes in fertility. But cancer is, according to the CDC. People who develop cancer from an HPV infection might require chemotherapy, radiation, or a hysterectomy, all of which have the potential to cause fertility issues. So in an indirect way, the HPV vaccine actually protects fertility.
Do Boys Need the HPV Vaccine?
Although cervical cancer is the most common cancer caused by HPV, and the most prevalent worldwide, HPV can also cause penile cancer, cancer of the throat and mouth, and anal cancer. A new study even found that if 80 percent of teens get vaccinated against HPV, the shot could prevent nearly one million cases of male oropharyngeal cancer this century. In other words, kids of all genders and bodies need protection from HPV.