Dr. George Papanicolaou and Dr. Herbert Traut proposed the vaginal smear as a method of detection of cervical cancer screening in 1943. Due to the widespread use of the Pap smear and its impact on the incidence of cervical cancer, this screening was one of the most important public health advances of the 20th century. Public health policies used in developed countries have significantly lowered the incidence of cervical cancer. It is unfortunate, however, that cervical cancer still represents the second most common malignancy among women worldwide, causing more than 273,500 deaths each year.
Human papillomavirus (HPV) is the main causal factor in the development of dysplasia, a pre-cancerous change in cells and tissues, and cancer of the cervix. Since 1970, it has been shown that the HPV genomic sequences are incorporated into the cervical cancer cells. The prevalence of HPV varies by location and ranges from one to 26 percent. The lifetime risk of HPV infection for sexually-active individuals in the United States is 50 percent, and by age 50, at least 80 percent of women have been infected.
The association between HPV and cervical cancer, accompanied with knowledge of the virus and related tumorogenic mechanisms, has led to development of HPV vaccines. Th e first vaccine, the HPV-16 L1 VLP vaccine, made by Merck Research Laboratories, was well-tolerated and highly immunogenic. A landmark study published in 2002 by Dr. Laura Koutsky and colleagues showed the vaccine to be 100-percent effective against persistent infection. That is, compared to the control group, there were no HPV infections specific to this type in the study population. There were some transient infections noted during the study period, but these cleared.
The second vaccine to be developed was the bivalent HPV-16/18, developed by GlaxoSmithKline. The vaccine was 100 percent and 95 percent in preventing persistent infection due to the HPV-16 and HPV-18, respectively. Furthermore, these studies revealed the potential benefit of a combined vaccination against various HPV types.
Since genital warts are common among young adults and the vast majority of these lesions are caused by HPV types 6 and 11, Merck developed a quadrivalent vaccine consisting of the L1 major capsid proteins of HPV types 6, 11, 16 and 18. This then combines in a single vaccine 70 percent of the HPV types which cause cervical cancer and 90 percent of those causing anogenital warts. The combined efficacy for this preparation was 90 percent against the types carried in the vaccine.
Due to the notoriety of the HPV vaccine, local health departments, pediatricians and other primary care providers have been faced with the responsibility to young girls, their parents and adult females about the importance of cervical cancer prevention. Local health departments and other health care providers in Illinois have been advocates for cervical cancer prevention and have promoted and advocated for the HPV vaccine.
The vaccine has been recommended by the CDC and Prevention Advisory Committee on Immunization Practices as a routine vaccine for girls of ages 11 to 12. The series can be started for girls as young as nine years old. It is also recommended as a “catch-up” vaccine for unvaccinated girls and women 13 to 26 years old. The target population for the vaccine is females nine to 26 years of age who have not been previously exposed to HPV.
The vaccine will not provide protection against all types of HPV, and it is most effective on young girls before they become sexually active. Research has not shown how long the protection of the vaccine will last or if one can expect long-term adverse health outcomes. The three-shot series will probably protect a female from an infection which can be acquired through sexual contact; however, research on the vaccine continues with reportable outcomes, and the CDC and FDA continue to monitor the safety of the vaccine after general use. The vaccine does not reverse any of the HPV viruses known to cause cervical cancer, nor does it treat existing HPV infections or complications.
The controversy began as states considered the vaccine to be added to the list of required routine immunizations. Texas was the first state in which the vaccine was made mandatory for all girls entering sixth grade. Later, the Texas legislature overturned the ruling. Other states have allowed parents an “opt-out” option for their young daughters. Illinois is among the states where legislators advocated for the vaccine to be mandatory. At this time most local public health agencies in Illinois and across the country have remained neutral on the decision of a mandatory HPV vaccine, but they still encourage the vaccine to be given because of its high prevention rates.
Another controversy regarding the HPV vaccine is that parents might feel that they are promoting early promiscuous sexual behavior by introducing the topic and the vaccine to their young daughters. Some feel that the government should not be the main decision maker on whether to make the vaccine mandatory and that local public health officials and physicians should be more vocal. Many have voiced some levels of fear of the unknown health risks in post-vaccine exposure.
For those readers wanting more data on the safety update of the vaccine, the Advisory Committee on Immunization Practices has developed a report, Quadrivalent Human Papillomavirus Vaccine (HPV4): United States Post-Licensure Safety Updates. The materials include information collected from seven clinical trials and include 11,778 females, ages nine to 26, who received the vaccine and 9,686 who received a placebo vaccine. The most commonly reported adverse reactions were pain at the injection site, swelling and erythema. The most commonly reported systemic events were fever and nausea. Deaths that were reported in the document were connected to other variables and could not be concluded as a result of the vaccine.
HPV Vaccine Usage in Illinois
Local public health agencies in Illinois have seen a steady usage of the vaccine. The Illinois Vaccines For Children Program announced that, beginning January 1, 2007, the HPV vaccine would be available for females ages nine to 18 who are eligible in the VFC program and under-insured females ages nine to 18. These individuals may receive the vaccine at an Illinois Federally Qualified Health Center (FQHC).
For Peoria County, from January through August 2007, more than 385 doses of the vaccine were given to females nine to 44 years of age, with 13- to 18-year-olds being the largest recipient group. Local physician practices have ordered more than 950 doses and have given slightly more than 400 doses from January to July 2007.
So what is the usage of the vaccine in other counties within Illinois? One southern county with a population of about 260,000 stated that its immunization clinic has been “aggressive with the vaccine,” and they have given more than 200 doses (no time period provided). They stated that they give the vaccine daily. The nursing director of the health department of another southern county stated, “We have been giving about 15 doses each month since March…activity is slow, but steady.”
One public health administrator from a county in central Illinois stated that they are “giving the vaccine to eligible 9- to 18-year-olds through the VFC program, and that their local Planned Parenthood office will be giving the vaccine as well.” A nurse from a northern county health department stated, “We have done approximately 250 girls, which is about 10 percent of our population…parents and families seem to be well-informed and eager to protect themselves and their daughters from cervical cancer.”
The majority of local public health agencies in Illinois agree that the state has a strong immunization program and are not currently interested in adding another mandatory routine vaccination at this time, nor are they interested in initiating the practice of allowing parents “opt-out” options for required routine vaccinations. We will continue to advocate, educate and provide the HPV vaccine, understanding that, at one point in time, all vaccines were new, with parents fearing the unknown long-term health risks. But remember, we have fewer to no cases of measles, mumps, rubella, polio and tuberculosis. Look at the vaccinations we have added in the last twenty years: RSV, Haemophilus influenza (Hib) and Hepatitis B, which is now one of our mandatory vaccinations. The medical community and public health agencies will continue to provide the HPV vaccine and monitor the outcomes to ensure a safe and healthy population, possibly making one more preventable disease—cervical cancer—a disease of the past. TPW