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UTHealth experts answer questions about the most common sexually transmitted disease in the US, human papillomavirus (HPV): Who should be vaccinated and at what age, how oral cancers are related, how women’s heart disease may be linked, and many others.
As recently as late October 2011, an advisory committee of the US Centers for Disease Control and Prevention (CDC) made national headlines when it recommended that middle school-aged boys also be routinely vaccinated to protect against HPV – the same recommendation the committee gave five years before for middle school-aged girls to protect against cervical cancer from HPV.
The decision of the CDC’s Advisory Committee on Immunization Practices (ACIP) for routine immunization of 11- and 12-year-old boys comes at a time when the HPV vaccine is still the subject of controversy, not for its safety and efficacy, but because its recommended use involves pre-teens. HPV spreads through direct sexual contact, and some believe that administering the vaccine to young girls and now young boys may encourage early sexual activity.
However, the CDC says that routinely vaccinating boys will help prevent the spread of the virus, as well as prevent certain cancers. And, administering the vaccine before an individual becomes sexually active and at risk of contracting HPV is the most effective time.
Human papillomavirus is the most common sexually transmitted infection in the United States with more than half of sexually active females and males infected with HPV at some point in their lives. Statistics from the CDC state that approximately 20 million Americans currently are infected with HPV with an additional six million people newly infected each year.
Individuals infected with HPV typically have no symptoms. Often, the infection clears up on its own without treatment. However, certain HPV types do not clear up, and the infection leads to genital warts, pre-cancer and cancer of the cervix, vulva and vagina. More rarely (see questions and sidebar), HPV is associated with cancer of the penis, anus, and certain cancers of the mouth and throat.
To answer some of our questions related to HPV, HealthLeader spoke with two experts: Stephen K. Tyring, MD, PhD, one of the research investigators of the HPV vaccine and clinical professor of dermatology, microbiology/molecular genetics and internal medicine at The University of Texas Health Science Center at Houston (UTHealth) Medical School; and gynecologic oncologist Larissa A. Meyer, MD, assistant professor of obstetrics, gynecology and reproductive sciences at UTHealth Medical School.
Q. Why has it taken so long to recommend that men and boys get the vaccine?
A. Dr. Stephen Tyring: Because the vaccine that protects against four HPV types [Gardasil]—the vaccine recommended for males— was first studied in women. Women were studied first because they are more likely than men to develop ano-genital cancer if not vaccinated.
Dr. Larissa Meyer: All the initial studies were done with a focus on pre-cancers of the cervix. In 2009, the Food and Drug Administration licensed the quadrivalent HPV vaccine for use in men and boys for prevention of genital warts. New data emerged demonstrating the efficacy of the quadrivalent HPV vaccine in preventing precancerous anal lesions leading the FDA in 2010 to approve the vaccine for prevention of pre-cancers and cancers of the anus.
Q. There are so many different strains of HPV. Can you discuss how the vaccine works and which strains it targets?
A. Tyring: There are more than 100 known types of HPV, and there are two available vaccines. One vaccine (Cervarix) protects against the two most common cancer types, HPV 16 and HPV 18. The other vaccine (Gardasil) protects against those two types, as well as the two most common types that can cause ano-genital warts, HPV 6 and HPV 11. [Since Gardasil covers four strains, it is called a quadrivalent vaccine.] Both of these vaccines use copies of the viral proteins and, like all vaccines, boost the immunity of the patient to prevent infection.
Q. Are females using these vaccines?
A. Meyer: The ACIP recommends the HPV vaccine for 11- to 12-year-old girls, for teen girls and for young women through age 26 who have not already received the vaccine. This recommendation by ACIP was announced in June 2006. Even though the quadrivalent HPV vaccine (Gardasil) is covered through the Vaccines for Children Program, usage has been disappointing for such an important cancer prevention tool. Nationally, uptake is estimated at 37 percent.
There’s been a recent connection between HPV and heart disease in women...
Meyer notes this research data is very new, with findings published Nov. 1 in the Journal of the American College of Cardiology. Physician-researchers reviewed HPV and heart disease data from a diverse group of 2,450 women, ages 20 to 59, who participated in the National Health and Nutrition Examination Survey in 2003-06, a large federally funded study
Meyer: They found a small group of 60 women who had suffered a stroke or heart attack. Vaginal swabs from these women were tested for the presence of 13 types of HPV defined as either cancer-causing or cancer-associated. Samples from nearly a quarter of the women tested positive for cancer-associated HPV. Women with those strains tended to be younger and have a greater prevalence of cardiovascular disease than the uninfected women.
The researchers’ proposed mechanism involves the tumor suppressor protein P53, which is decreased by HPV. Decreased P53 also is associated with an increase in atherosclerosis or hardening of the arteries.
While this data is exciting, it is not definitive proof. I look forward to further research in this area that not only may help to better understand the pathogenesis of cardiovascular disease but also how the vaccine may contribute as a novel way of preventing severe cardiovascular events.
Q. How safe and how effective are HPV vaccines?
A. Tyring: The two available vaccines are very safe and almost 100 percent effective.
Q. Why aren’t more people getting vaccinated?
A. Meyer: Multiple factors have contributed to the low vaccination rate among adolescents especially. Studies have shown that the most common reasons that led parents to not have their girls vaccinated was a belief that the child did not need the vaccine, a lack of knowledge of the vaccine and the belief that their child was not sexually active.
Physician behavior also may contribute. Given that the vaccine was initially only recommended for girls and young women, remembering to offer the vaccine to boys and young men and feeling sufficiently trained to discuss the risks and benefits may have affected the uptake as well.
Because individuals need three separate doses of the HPV vaccine within a six-month period, patient compliance and follow-through can be another obstacle.
The issue, especially if you’re dealing with adolescents or kids, is that they are relying on their parents to take them to the doctor’s office three separate times. They may get one shot, but to get people to come back to finish the series is a bit more difficult.
Q. Should we be mandating the HPV vaccine to our younger children?
A. Both Tyring and Meyer agree that vaccinating young children against HPV is a good choice. They explain their viewpoints.
Tyring: With the understanding that “mandating” means that the children/parents can “opt out” of receiving it and that the government will pay for the vaccine for children who cannot afford it, this mandate would be good. Younger children should receive it, because if we wait until they are teenagers or adults, the probability that they will become infected with HPV goes up. Therefore, this vaccine, like all vaccines, would not be useful in someone who is already infected.
Meyer: I believe that we should be strongly encouraging the vaccine for all children, boys and girls alike. The vaccine should be offered and endorsed in a similar fashion to the flu vaccine, chicken pox vaccine, and other important childhood vaccines. It is a terrible thing to see a woman die from a largely preventable cancer. Any step we can do to prevent cervical and other HPV- associated cancers is important.
Q. Is there a test to show that males have HPV or carry it?
A. Meyer: Currently, there is no test to find HPV in men. The only approved HPV tests on the market are not useful for screening for HPV-related cancers or genital warts in men.
Q. If a young woman comes up positive for one strain, should she still get the vaccine?
A. Tyring: Yes, if she already has one type of HPV, the vaccines will protect her against the other one or three common HPV types, respectively, which she does not already have and that the particular vaccine is designed to protect against.
By Roberta B. Ness, MD, MPH, dean of the UT School of Public Health and Maria Fernandez, PhD, associate professor, UT School of Public Health
Should my child be vaccinated with the HPV vaccine? This question has been so muddied by politics and misinformation that many parents are doing the wrong thing. That wrong thing is to avoid vaccination.
Q. Once a woman is infected, and then has the lesions removed or the affected part of the cervix removed, does she still “have” HPV?
A. Meyer: While the goal of such surgical procedures is to remove abnormal cells, HPV can be “multifocal” and removing all areas can be difficult. The virus can remain and cause additional abnormalities if not cleared by the immune system. For this reason, it is very important for individuals who have been affected by HPV- related changes to have regular follow-up with their physician. HPV infection can be a persistent problem requiring multiple therapies, especially in individuals with suppression of their immune system such as HIV, the transplant community, as well as smokers.
Q. Is there an age when sexually active people are less susceptible to HPV infection?
A. Meyer: While people are susceptible at any age, some experts have advocated delaying intercourse until at least age 20. In teenage girls, the cervix is still immature and is thought to undergo certain normal changes associated with growth and development. So, a teenage girl’s cervix may be more sensitive to infection with HPV and at greater risk for abnormal cell changes. Delaying intercourse also may theoretically decrease the number of partners a woman has in her lifetime. Limiting the number of sexual partners and using condoms also may reduce your chances of getting HPV and its associated cancers.
Q. How long does it take for one of the high-risk HPV strains to possibly cause cancer of the cervix?
A. Meyer: It is thought to take approximately 10-15 years for cervical cancer to develop. The most important thing a woman can do is to get regular screening from her gynecologist [or primary care provider] for cervical cancer through a Pap smear [or Pap test]. About six out of 10 women who are diagnosed with cervical cancer either have never had a Pap test or have not had a recent Pap test.
Q. Can a mother pass HPV on to her newborn baby unknowingly?
A. Meyer: Yes, very rarely, genital HPV infections can be transmitted from mother to baby during delivery. It can lead to a rare condition called recurrent respiratory papillomatosis (RRP), which manifests as warts in the respiratory tract of the baby.
Because it is not clear whether delivery by Cesarean section prevents RRP, routine Cesarean section delivery is not recommended just to prevent HPV infection in the newborn. However, if a woman has extensive warts that would obstruct a vaginal delivery or if there is risk of extensive bleeding from the genital lesions, then Cesarean section delivery is warranted.
Q. What is the connection between HPV and head and neck cancers? Is oral sex the link?
A. Meyer: Recent studies show that about 60 percent of oropharyngeal cancers [cancers of the back of the throat, including the base of the tongue and tonsils] are linked to HPV. The increasing prevalence of oral sex is one factor thought to be contributing to this rise.
The incidence of HPV- related head and neck cancers has increased over the last decade. HPV- related cancers of the head and neck are much more common in men than women. In fact, among the sites of HPV-associated cancers occurring yearly in the United States, the oropharynx is the second most common after the cervix.
The natural history of oral HPV infection and the conditions in which oral HPV infection may lead to cancer are uncertain. Just like with genital HPV infection, certain subtypes are thought to be associated with warts, while others with precancerous changes or cancer.
Q. Can you always see or feel HPV-related lesions in the mouth or throat?
A. Meyer: Often, individuals may have more subtle findings, such as a persistent sore throat, changes in the voice, hoarseness, pain or difficulty swallowing, pain while chewing, a lump in the neck, or non-healing sores.
Q. Can you catch HPV from kissing?
A. Meyer: The connection between HPV infection and kissing is not as clear. There are no epidemiological studies that directly address oral-to-oral transmission of HPV. However, some studies have linked oral HPV infection with a history of open-mouthed kissing and oral sex. Rare cases have described husband-wife pairs with HPV- positive cancer of the tonsils.
Q. Are the same HPV strains that develop into cervical cancer also responsible for head and neck cancers?
A. Meyer: High-risk types, HPV-16 and HPV-18, are thought to be associated with approximately 70 percent of cervical cancers. However, HPV-16 alone is thought to be associated with an even greater proportion – 85 percent – of HPV-positive oropharyngeal cancers.
For more information on HPV-related conditions, vaccines and treatments, please visit the CDC website for Human Papillomavirus (HPV).
Send us your questions for the experts, comments or suggestions.
Last Updated: 2-01-2012
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Dr. Stephen Tyring is a clinical professor of dermatology at the UTHealth Medical School.
Dr. Larissa A. Meyer is an assistant professor of obstetrics, gynecology and reproductive sciences at UTHealth Medical School.
Simple Ways to Help
Young and Old Eyes
May is Healthy Vision Month and it is imperative to take care of eyes whether they’re young or old.
Children should have their vision checked by age 6, even if there aren’t any signs of eye problems. Healthy eyes and vision are very important to a child’s development. Finding and treating eye problems early on can save a child’s sight. Two common eye problems in children are:
Both of these eye problems can be treated if they are found early.
Here are ways to help your child develop vision skills:
Don’t let poor vision put elders at risk. Leave a three-foot, clear path through each room of their house. Outline edges of steps, coffee tables, doorways and bathtubs with colored tape to contrast with surrounding areas. Install lights along outdoor pathways and keep foyers well lit to avoid having to enter dark areas. Replace switch plates with colors that contrast with walls, or outline them with tape of contrasting colors. It is also always smart to use nightlights during the night.
