Cervical Cancer and the HPV Vaccine
ABOUT HPV AND CERVICAL CANCER
Human papillomavirus (HPV) is the most commonly sexually transmitted infection (STI) in the United States. The HPV family contains over 100 different types of the virus, and is responsible for problems such as common warts, plantar warts, skin cancers, genital warts, genital cancers, and cervical cancer (Schmidt, 2007). Infection can be spread through intercourse or non-intercourse genital contact (Gray, 2007). Over fifty percent of sexually active men and women will be infected with one or more of the virus types at some point in their life (Koutsky, 1997), and of those infected over half are between the ages of 15 and 24 (Cates, 2006). Most forms of HPV are asymptomatic and will resolve themselves without any medical attention, but some infections could persist for years or remain dormant in the cell lining of the cervix, causing serious problems even years later (FDA, 2006).
According to most scientific studies, over 90% of cervical cancer cases are caused by HPV. Cervical cancer is the second-most common cancer worldwide. It affects about 16 per 100,000 women per year and causes death in about 9 per every 100,000 per year. In the United States, cervical cancer is the eighth-most common cancer. But even though the U.S. incidence and mortality rates for cervical cancer are about half that of the rest of the world, mostly due to the success of Pap smear screening (http://www.aafp.org), it is by no means a small problem. The American Cancer Society estimated that 3,700 women would die of cervical cancer in the United Sates in 2006, and that about $4 billion would be spent on management of HPV (ACS, 2006). That makes HPV the second most costly sexually transmitted infection in society.
In June 2006, FDA approved Merck & Company’s vaccine Gardasil, which protects against four strains of HPV (FDA, 2006). Two of the strains (types 16 and 18) are responsible for 70% of cervical cancers, and the other two strains (types 6 and 11) account for 90% of genital warts (Frazer et. Al., 2006). It only works if given before infection occurs, so the company recommends vaccination as early as 9 years old, before girls become sexually active.
Randomized controlled trial of HPV vaccines were carried out to determine the long-term effectiveness and safety of these vaccines (Harper, 2006). The study included 776 women who received three doses of the bivalent HPV-16/18 virus-like particle AS04 vaccine or a placebo. During the follow-up period, the researchers monitored cervical sampling for HPV DNA testing, cervical cytology, and blood tests for immunologic responses. Participants also had to report any new onset of chronic disease, any condition that required medical attention, or any serious side affect experienced during the follow-up study. The average follow-up lasted 47.7 months.
In the treated group, patients showed a strong positive immunologic response. Although the vaccine had no positive effect on patients previously infected with HPV, the immunization was effective for preventing new infections. Only two out of 353 immunized women developed new HPV-16 infections, and two out of 352 women taking the placebo developed new mixed HPV-16/18 infections during the extended follow-up. In women assigned to placebo, the following new infections were documented: HPV-16, 21 infections; HPV-18, 11 infections; mixed HPV-16 and HPV-18, 28 infections. The study showed that the vaccine was 95.8 percent effective against new HPV-16 infections, 100 percent against new HPV-18 infections, and 96.9 percent against mixed infections. The vaccine also showed similar effectiveness against both incident and persistent infections. Adverse events were more common in the placebo group than in the vaccine group (22 percent versus 14 percent), but the researchers suggest that these events were not related to the immunization.
The study concluded that the immunization provided effective protection against HPV-16 and HPV-18 infections. The vaccine protection appears to last for four to five years.
The FDA approved the vaccine after only 6 months testing. Four studies were conducted around the world, showing that Gardasil was successful in preventing HPV infection, but none of the studies were long enough to track the formation of cervical cancer. The manufacturer has agreed to conduct several more long-term studies, but results will not be available for several years.
According to a Wall Street Journal Online/Harris Interactive health-care poll, a majority of Americans do support the widespread use of the HPV vaccine (http://online.wsj.com/article/SB115464198706026167.html). The online poll found that 70% of U.S. adults believe that encouraging girls and young women to get the vaccine is a good way to prevent the spread of cervical cancer, while only 7% disagree and 23% are not sure. Also, 50% of those polled said that the vaccine should be part of the vaccine routine for all children and adolescents, while 21% disagree. On the flip side, 44% of the poll participants said that abstinence programs are a better way of preventing HPV than medical treatment, while 40%disagreed. In addition to these statistics, the vaccine is facing vehement opposition from many Christian and conservative groups. Opponents say that the vaccine itself is a good thing, but the decision to get the vaccination should be left up to the parents or guardians of the girls. Since cervical cancer is an STI, and factors such as numerous sexual partners increase the risk of contraction, some conservatives and parents-rights groups say that requiring the vaccine would encourage premarital sex and sexually promiscuous behavior, as well as infringe on the rights of the parents in raising their children. As the Family Research Council stated, “While we welcome medical advances such as an HPV vaccine, it remains clear that practicing abstinence until marriage and fidelity within marriage is the single best way of preventing the full range of sexually transmitted diseases” (Stein, 2005).
Since the target of the vaccine is preadolescent children, parental support for this vaccine is critical for its success. A study was conducted to: (1) to determine the overall acceptance of HPV vaccines for preadolescent children by parents, (2) to evaluate the influence of written educational information about HPV on parental acceptability of HPV vaccines, and (3) to identify independent predictors associated with HPV vaccine acceptability by parents (Dempsey, 2006). A randomized intervention study within a cross-sectional survey was conducted. Parental HPV vaccine acceptability was measured under 3 different hypothetical scenarios. A self-administered survey on the knowledge, attitudes, and beliefs about HPV and HPV vaccines was sent to 1600 parents of 8- to 12-year-old children. In addition to the short description of HPV and the vaccine which was given to all of the parents, half of the study group received detailed "HPV Information Sheets" describing the epidemiology and clinical significance of the HPV infection. The results of the study showed that parents who received the HPV information sheet had higher mean scores on the HPV knowledge assessment tool than the control group, but, there was not a statistically significant difference in HPV vaccine acceptability between the 2 groups. This study indicated that providing parents with an HPV information sheet did seem to improve knowledge about HPV, but this increased knowledge had little effect on the acceptability of these vaccines by parents for their children. Instead, attitudes and life experiences seemed to be more important factors influencing HPV vaccine acceptability among parents (Dempsey, 2006).
POLITICAL/ECONOMIC IMPLICATIONS OF THE VACCINE
On Friday, February 1, 2007, the Governor of Texas, Rick Perry, issued an executive order mandating that all girls entering the sixth grade in Texas must get the new vaccine, Gardasil, before they can enroll. Perry is a conservative Republican, but he is coming under fire from conservatives in both the political and social angles for requiring this very new, very expensive vaccine for a sexually transmitted cancer. Perry, however, maintains his decision, saying that the cervical cancer vaccine is no different than the vaccine against polio. “If there are diseases in our society that are going to cost us large amounts of money, it just makes good economic sense, not to mention the health and well-being of these individuals to have those vaccines available.”
It is true that cervical cancer is responsible for the spending of billions of healthcare dollars every year, but there is also other money at stake. The vaccine is composed of three shots totaling $360, and Merck, the drug company that owns the vaccine, is reportedly spending millions of dollars to try to convince governments to require it (CBS, 2007). Merck has doubled its lobbying budget in Texas and has funneled money through Women in Government, an advocacy group of female state legislators around the country. A top official from Merck’s vaccine division sits on the group’s business council, and Women in Government has been responsible for introducing many of the state bills for adopting the mandatory vaccine. Analysts and investors predict that Gardasil (the vaccine) will be at least a billion dollar profit for Merck. Governor Perry also has multiple ties to Merck and Women in Government. The drug company has recently hired a new Texas lobbyist, Mike Toomey, who also happens to be Perry’s former chief of staff. Perry’s current chief of staff’s mother-in-law, state Rep. Dianne White Delisi, is a state director for Women in Government. Perry also received $6,000 from Merck’s political action committee during his reelection campaign. Merck spokeswoman Janet Skidmore refused to release how much money the company is spending on lobbyists, or how much money it gave to Women in Government. The group’s president, Susan Crosby, also refused to specify how much money the drug company gave to the group. Although Texas is but one state, it was the first to take the initiative on the vaccine. And since laws regarding immunization and consent of minors fall under state jurisdiction, (Schmidt, 2007), it is likely that other states will face similar conflicts-of-interest involving public health and economic motives.
The price of the drug itself is also under fire. Even though most state mandates-in-the-works include an opt-out option for parents with religious objections, most families will still be forced to get the most expensive vaccine in history. At almost $400 dollars a vaccine, many families cannot afford the shots, especially if they have more than one daughter. Many doctors, too, cannot afford to stock Gardasil, and doctors from Arizona to New York are refusing to stock Gardasil because of its steep price and inadequate reimbursement from most insurers. Many practices must invest $50, 000 or more in vaccine inventory, multiple refrigerators, and insurance. They also have to absorb the costs of wasted or broken vials, because most insurers reimburse just $2 to $15 dollars for the $120/dose charged by Merck. To cover these problems, many doctors are charging up to $450 a vaccine. Pediatricians and gynecologists contacted the Associated Press and said that they would, at best, break even if they stocked the vaccine.
Based on the results of numerous clinical trials, there is every indication that the use of human papillomavirus (HPV) vaccinations will help prevent cervical cancer. With 10,370 new cases a year and 3,710 women in the United States still dying from this disease annually, it seems obvious that the HPV vaccine would become part of routine immunization. Due to the nature of the disease however, and the surrounding social implications, implementation of the vaccine is not a black and white issue. Infection with the virus is acquired by sexual intercourse, and the risk of infection is related to the number of sexual partners as well as other factors. Immunizing young before sexual activity could be seen as accepting or even promoting sexual promiscuity. Do to the sexual basis of the disease, attempting to screen for persons “most at risk” raises issues such as confidentiality and stigmatization. Making the vaccine mandatory for such young children also raises issues of parental choice and control, since another disease prevention method is behavior control. Studies also indicated that increased knowledge of the HPV virus did not necessarily change the opinions of parents regarding the vaccine, indicating that prejudice against the vaccine could be deeply rooted. At the time of this article, Merck is the sole provider of the HPV vaccine, which raises further questions of economic and healthcare interests. The vaccine can provide the protection against the HPV virus, but the success of the drug is overshadowed by the social aspects of its implementation.
American Cancer Society. (2006). Detailed guide: Cervical cancer. What are the key statistics about cervical cancer? Retrieved September 20, 2007, from http://www/cancer.org/docroot/CRI/content/CRI_2_4_IX_What_are_the_key_statistics_for_cervical_cancer_8.asp?sitearea.
Bright, Beckey. (2006, August 8). Majority of Americans back HPV vaccine, poll shows. Wall Street Journal. Retrieved September 20, 2007, from http://online.wsj.com/article/SB115464198706026167.html.
Cates, W., Jr. (2006). Estimates of the incidence and prevalence of sexually transmitted diseases in the United States. American Social Health Association Panel. Sexually Transmitted Diseases, 26, S2-S7.
CBS. (2007, February 2). Texas mandates cervical cancer vaccine. Retrieved on September 20, 2007, from http://www.cbsnews.com/stories/2007/02/02/health/main2427919.shtml.
Dempsey, A.F., Zimet, G.D., Davis, R.L., & Koutsky, L. (2006). Factors that are associated with parental acceptance of human papillomavirus vaccines: A randomized intervention study of written information about HPV. Pediatrics, 117, 1486-1493.
Frazer, I.H., Cox, J.T., Mayeaux, E.J.,Franco, E.L., Moscicki, A.B., Palefsky, J.M., et. al. (2006). Advances in prevention of cervical cancer and other human papillomavirus-related diseases. Pediatric Infectious Disease Journal, 25(2), S65-S81.
Goeser, A. (2007, August 15). Quadrivalent HPV Recombinant Vaccine (Gardasil) for the Prevention of Cervical Cancer. American Academy of Family Physicians. Retrieved on September 20, 2007 from http://www.aafp.org/afp/20070815/steps.html.
Gostout, Bobbie, M.D. (2007, May 16). Cervical cancer vaccine: who needs it, how it works. Retrieved from http://www.mayoclinic.com/health/cervical-cancer-vaccine/WO00120.
Gray, Julie R. (2007, April/May) HPV vaccination: should it be mandatory for entry into public school? Nursing for Women’s Health. Vol. 11, Issue 1, pg. 83-87.
National Cancer Institute. (2002). Clinical trial results: Vaccine protects against virus linked to half of all cervical cancers. Retrieved September 18, 2001, from http://www.cancer.gov/clinicaltrials/results/cervical-cancer-vaccine1102.
Harper DM, et al. (2006, April 15) Sustained efficacy up to 4.5 years of a bivalent L1 virus-like particle vaccine against human papillomavirus types 16 and 18: follow-up from a randomised control trial. Lancet. 367:1247-55.
Koutsky, L.A. (1997). Epidemiology of genital human papillomavirus infection. American Journal of Medicine, 102, 3-8.
Schmidt, Judy V. (2007, February/March) HPV vaccine: implications for nurses and patients. Nursing for Women’s Health. Vol. 11, Issue 1, pg. 83-87.
Stein, Rob. (2005, October 31). Cervical cancer vaccine gets injected with a social issue. Washington Post. Retrieved from http://www.washingtonpost.com/wp-dyn/content/article/2005/10/30/AR2005103000747.html.
U.S. Food and Drug Administration. (2006). FDA licenses new vaccine for prevention of cervical cancer and other diseases in females caused by human papillomavirus. Retrieved September 21, 2007, from http://www.fda.gov/bbs/topics/NEWS/2006/NEW01385.html.
Wisconsin Department of Natural Resources. (2001). Glacial habitat restoration areas. Retrieved September 18, 2001, from http://www.dnr.state.wi.us/org/land/wildlife/hunt/hra.htm
The Health Psychology Home Page is
produced and maintained by David Schlundt, PhD.
Vanderbilt Homepage | Introduction to Vanderbilt | Admissions | Colleges & Schools | Research Centers | News & Media Information | People at Vanderbilt | Libraries |Vanderbilt Register | Medical Center
|Return to the Health Psychology Home Page|
|Send E-mail comments or questions to Dr. Schlundt|