Challenging Dogma - Spring 2008

...Using social sciences to improve the practice of public health

Monday, April 21, 2008

Public Health and the Human Papillomavirus (HPV): A Closer Look - Toni-Ann Saunders

Cervical cancer is caused by an untreated infection with the Human Papillomavirus (HPV). This cancer causes approximately 9,700 deaths in women a year and is the eleventh leading cause of death among American women. The Centers for Disease Control and Prevention (CDC) estimate that at least 80% of women in the U.S. are infected with HPV by age 50 (6).

Despite its potential effects on all sexually active women, it is disportionately a disease of women who do not receive regular gynecological exams, such as a pap smear. Women who are greatly affected tend to be of low socioeconomic status (SES), minorities, and less likely to have regular pelvic exams. Research shows that black women, particularly those who live in the rural south, as well as Asian and Hispanic women are at higher risk of cervical cancer incidence and mortality. This is due to access to care and social and cultural factors (9).

Given the severity of this relatively preventable disease it is necessary and expected that the public health community intervenes. The cervical cancer and HPV campaign was spurred by the introduction of the HPV vaccine, marketed as Gardasil, in 2006. Since then controversy has surrounded the utility of this vaccine among females between the ages of 11 and 26 years old.

Some of the controversies stem from the ethical utilization of this drug among 9-12 year old girls. Although the vaccine is most effective before exposure to HPV, some activists and physicians believe that this age group is too young, while other public health experts believe that is the best age to target since they are unlikely to be sexually active and have any of the strains of HPV. This divide among experts is a good springboard for discussion regarding measures for prevention.

Currently, the reasons why HPV and cervical cancer prevention efforts have been a public health failure are (1) efficacy and policy issues are not well defined, (2) there is no discussion of social and cultural difference among women at risk for HPV exposure, and (3) education about prevention of this disease is lacking among women.

Influence of HPV vaccine efficacy on public policy
The prevalence of cervical cancer is highest among middle age women despite that there is a push for vaccinations for young girls starting at age 9. The rational for vaccination at this young age is that they are unlikely to be infected with HPV. Efficacy studies for this vaccine, however, had a low age limit of only 16 years old, therefore advocating for shots in a younger age group may be risky. Also, there are likely to be more adolescents and women who have been exposed to at least one strain of HPV so to emphasize a vaccine that may not protect them at this point is a dangerous message.
Positive clinical trials findings, from over 12,000 women aged 16-26 among several countries, have been reported about the effectiveness of Gardasil in protecting against the 2 strains (HPV 16 and 18) that cause 70% of cervical cancer. Nevertheless, there have not been longevity studies done beyond four years to track whether this efficacy continues throughout the lifetime of the immunized woman. Moreover, since the age group enrolled in the study is older (16-26) and more likely to be sexually active than a nine year old it may not be a fair comparison.

Other issues that arise about the efficacy of this vaccine is that it costs $360.00 to administer the full series while a pap smear costs about $10.00 to administer. In light of the cost differential between these two prevention methods public health officials promoting this vaccine should be aware that barriers might exist for women. For example, women who do not have insurance or other means to cover the cost of this potentially beneficial vaccine will be at a disadvantage. Given that an aim of public health is to promote and not preclude health and wellness the focus should be on emphasizing the importance of regular pelvic exams including pap smears.

Social and cultural factors that influence a woman’s risk of HPV infection and cervical cancer
According to the American Cancer Society (ACS) disparities exist among racial and ethnic groups in terms of HPV infection rates and cervical cancer cases. These differences are not just due to access or lack of education but other social factors that involve interplay between the individual and the environment. For instance, studies show that the incidence and mortality of cervical cancer is 60% higher among black women compared with their white counterparts. Moreover, other racial and ethnic groups such as Vietnamese Americans, white women living in rural areas, and Hispanics living along the US-Mexico border have similar experiences of cervical cancer incidence and mortality as black women do (9).

Dr. Si Van Nguyen, an Asian physician, helps to elucidate this discrepancy among his Vietnamese population since issues regarding pelvic exams and pap smears are not discussed because they are seen as taboo. According to this physician, the social norms in this culture are not to discuss such issues. As a result these women are less likely during a doctor’s visit to have inquiries about cervical cancer, the HPV vaccine, or other prevention methods against cervical cancer. Although, other culture groups may have some working knowledge regarding HPV or the etiology of cervical cancer, factors such as mistrust or fear of the medical community make them less likely to seek out preventative care. It has also been shown that depending on whom you seek care from, such as a family practitioner verses a gynecologist, the perception of HPV as a problem will differ because of the physician’s knowledge and experience (11).

With this in mind, an effective public health campaign has to acknowledge these factors in order to be successful in its end objective, which is to reduce the incidence of cervical cancer. The HPV vaccine may only be one level of that story but should not be the entire solution. Other preventative measures such as education and regular pelvic exams in conjunction with pap smears will be more far-reaching and lasting than just vaccination alone.

Public health is failing to counter incomplete preventions messages about cervical cancer and the HPV vaccine
The role of public health in disease prevention is important, especially in underserved communities. A sense of responsibility is paramount in effectively educating and delivering care to the public. If the public health community believes that the HPV vaccine will be effective in decreasing the likelihood of girls and young women contracting HPV then it needs to ensure that they know the facts about HPV. Focus group studies have shown that adolescents and some women know very little about HPV and its association with cervical cancer (7).

Outlets for discussions about women health policy issues, such as Kaiser Family Foundation, show that only 40% of women ages 18 to 75 have heard of HPV. Of that group, less than half know that is associated with cervical cancer. Given that statistic, public health practitioners’ efforts are better spent increasing awareness and education among girls and women eligible to be vaccinated. Some issues of concern not being discussed are that the virus is contracted through sexual contact and the vaccine only protects against 4 of the 30 strains of the virus. Albeit those four strains are responsible for 70% of cervical cancer and 90% of genital warts, awareness of the effectiveness and limitations of the vaccine still needs to be paramount. These women also need to know that if they already have any or all of those 4 strains the virus is not as useful.

Public Health should be applauded for its agenda setting efforts by bringing the issue of cervical cancer and the HPV vaccine to light. Its focus though was too narrow and should have included a host of other factors rather than just jumping on the vaccination bandwagon. Although vaccinations could be seen as the most effective means to prevent cervical cancer there are feasibility issues such as (1) it is not known how the long term effects of this vaccine will play out, (2) there are social/cultural difference among women which impact their propensity to be at a higher risk for cervical cancer, and lastly (3) the lack of education and awareness of this disease that need to be discussed and implemented in a public health prevention campaign for cervical cancer.

1. The American College of Obstetricians and Gynecologists. Revised Recommendations for Women’s Health Screenings and Care. Washington, D.C: ACOG Women’s Health Care Physicians.
2. American Social Health Association. Frequently Asked Questions about cervical cancer/ HPV vaccine access in the U.S.
3. Centers for Disease Control and Prevention (CDC) podcast regarding Cervical Cancer, Pap Tests among Foreign-Born Women.
4. Coombes R.. Life saving treatment or giant experiment?. BMJ 2007; 334:721-723.
5. Dailard C. The Public Health Promise and Potential Pitfalls of the World’s First Cervical Cancer Vaccine. Guttmacher Policy Review Winter 2006; 9 (1): 6-9.
6.Kaiser Family Foundation. Women’s Health Policy Fact Sheet, January 2007.
7. Maghboeba M, El-Shaarawi N. “I have never heard that one”: young girls’ knowledge and perception of cervical cancer. Journal of Health Communication 2007; 12:707-719
8. Phenox J, et al. National Research Center for Women and Families Issue Brief, March 2007.
9. Saslow D. et al. American Cancer Society Guideline for Human Papillomavirus (HPV) Vaccine Use to Prevent Cervical Cancer and Its Precursors. CA: A Cancer Journal for Clinicians 2007; 57: 7-28.
10. Soni, A. Medical Expenditure Panel Survey. Statstical Brief #173. Agency for Healthcare Research and Quality. June 2007.
11. Umar KB. Breaking cultural barriers: cervical cancer in Asian American and Pacific Islander women. Office of Minority Health Resource Center, January/February 2004.
12. Villa, L.L. et al. Prophylactic quadrivalent human papillomavirus (types 6, 11, 16, and 18) L1 virus-like particle vaccine in young women: a randomized double-blind placebo-controlled multicentre phase II efficacy trial. Lancet Oncology 2005; 6:271-78.

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