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HPV: A Complicated Vaccine




The U.S. Food and Drug Administration has approved two vaccinations against human papillomavirus (HPV), but medical debate about the appropriate time of administration and the general population’s growing fears regarding the vaccines’ safety continue.

Paul Darden, MD, CMRI James Paul Linn Chair of Pediatrics, Chief of General and Community Pediatrics at the University of Oklahoma Health Sciences Center, co-authored a study published online in Pediatrics that illuminates rising percentages of vaccine declinations on the parts of parents contrasted by rising percentages of physicians recommending the vaccine. Dr. Darden says the vaccines — Gardasil or Cervarix — should be presented in the same manner as other vaccines.

“I approach the HPV vaccines as I approach other vaccines, which is not as anything special, but as necessary for the preventive care of children,” Dr. Darden explains. “The HPV vaccinations are exciting and different to present in some ways because while HPV is an infectious disease, the primary reason we vaccinate against it is to prevent cervical cancer.”

The National Cancer Institute (NCI) names HPV a major cause of cervical cancer, which accounts for nearly 250,000 deaths worldwide annually. Both vaccines effectively prevent types 16 and 18 HPV infections, which are linked to approximately 70 percent of cervical and anal cancers, according to the NCI. Neither protects against all strains of the virus.

A Question of When

Because the vaccines prevent rather than treat HPV, they should be administered prior to contraction to be fully effective. This means vaccination must ideally occur before people engage in sexual activity. A 2011 survey conducted by the Centers for Disease Control and Prevention (CDC) shows that nearly half of all American high school students reported having engaged in sexual intercourse. Yet, Dr. Darden’s study shows that parents cite sexual inactivity as one of the major reasons for declining the vaccine for their children.

This dichotomy leads Diane Harper, MD, MPH, MS, Professor of Medicine at the University of Missouri School of Medicine, who participated in early trials of the vaccines at the behest of their makers, GlaxoSmithKline and Merck & Co., to suggest that vaccination be based upon individual risk factors because studies have not shown how long the vaccines protect against HPV.

Dr. Harper sees merit in waiting until patients themselves determine the appropriateness of vaccination.

“I provide a balanced picture to my patients and their families and am not at all upset if they refuse the vaccine, especially at younger ages,” Dr. Harper says. “I think it may be more appropriate for some people to decide they want to be vaccinated at age 16, 18 or 20 — whichever age makes the most sense for them to have protection from infection.”

On the other hand, Dr. Darden notes that sexual activity doesn’t always happen as planned, and because of prevalent teenage sexual activity, Dr. Darden encourages vaccination before children enter high school.

“If you vaccinate after the patient is infected, the vaccine won’t help at all,” Dr. Darden notes. “The vaccine may not provide the protection we hope for, but it’s better than nothing — it’s the same reason why we give tetanus shots. I understand concerns that the vaccine doesn’t provide lifelong protection, but I don’t understand using that as an excuse not to vaccinate.”

Dr. Harper questions the appropriateness of routine early vaccination and pushes for an individualized approach to vaccine administration.

“The argument that someone should get the vaccine at age 11 because by the time they’re 18, they’ll have a 50 percent chance of having had sex and the vaccine won’t work, is true at face value,” Dr. Harper says. “But it may very well be that the age at which a person decides to get vaccinated is very personally determined. It’s much more appropriate to decide what the risk is as a family or as a person.”

Benefits of Vaccination

Although preventing cervical cancer is the primary goal of HPV vaccination, people can benefit from the vaccine in other ways. Dr. Harper co-authored a review paper published by the International Scholarly Research Network, in which she notes that the most beneficial results of vaccination are reductions in abnormal pap test results, colposcopies and excisional treatments.

“The importance of the vaccine is not [solely] one of cancer protection, but one of health economics in reducing the number of procedures a young person with HPV is likely to get in his or her lifetime,” Dr. Harper says.

Methods of Approach

In the Pediatrics study, which was published in March 2013, Dr. Darden shows that between 2008 and 2010, a little more than half of surveyed physicians recommended HPV vaccination to their teenage female patients. Dr. Darden explains that physicians have a duty to provide clearly stated recommendations to their patients.

“Sometimes, as physicians, we feel we’ve stated our recommendations, but to the other party, they remain unstated,” Dr. Darden says. “This can increase their uncertainty. Parents or patients can still refuse the vaccination, but the reason they’re coming to you is for your expert opinion, and I don’t think it’s fair to them not to give it.”

Dr. Harper agrees that, while physicians should clearly state their recommendations, they should not conform to messages sent by the CDC’s Advisory Committee on Immunization Practices.

“The message physicians have received ... is that you have to push the vaccine,” Dr. Harper says. “That’s absolutely the wrong way to present these vaccinations. What physicians need to be saying is that the vaccine is available, and it’s useful.”


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