Friday, October 10, 2008

Health Care and HPV

According to an article in the New York Times this week, one in four teenage girls have received the relatively new vaccine against cervical cancer. The figures represent the government’s first substantial study of vaccination rates for the vaccine, Gardasil, which is Merck & Company’s heavily advertised three-shot series that goes after the sexually transmitted human papillomavirus, or HPV. The vaccine protects against strains of the virus that cause about 70% of cervical cancers. Health officials recommend that girls get the shots when they are 11 or 12, if possible, before they become sexually active. Also, 11 is the age when children are generally due for a round of vaccinations. The survey covered children only from 13 to 17.

The results, according to the NY Times, are based on nearly 3,000 girls for whom the researchers could verify vaccination information through medical records. Proponents of the vaccine had been hoping for much higher vaccination rates, saying the shots could significantly reduce the nearly 4,000 cervical cancer deaths that occur each year in the United States. However, many families are cautious about the safety of new vaccines, and other aspects of the vaccine may also give some families pause. It is expensive, selling for about $375, although many health insurers now cover it. And there are questions about whether it confers lifetime immunity or if a booster shot will be needed.

According to the Centers for Disease Control (CDC), Most people with HPV do not develop symptoms or health problems. But sometimes, certain types of HPV can cause genital warts in men and women. Other HPV types can cause cervical cancer and other less common cancers, such as cancers of the vulva, vagina, anus, and penis. The types of HPV that can cause genital warts are not the same as the types that can cause cancer. HPV types are often referred to as “low-risk” (wart-causing) or “high-risk” (cancer-causing), based on whether they put a person at risk for cancer. In 90% of cases, the body’s immune system clears the HPV infection naturally within two years. This is true of both high-risk and low-risk types. Genital warts usually appear as small bumps or groups of bumps, usually in the genital area. They can be raised or flat, single or multiple, small or large, and sometimes cauliflower shaped. They can appear on the vulva, in or around the vagina or anus, on the cervix, and on the penis, scrotum, groin, or thigh. Warts may appear within weeks or months after sexual contact with an infected person. Or, they may not appear at all. If left untreated, genital warts may go away, remain unchanged, or increase in size or number. They will not turn into cancer. Cervical cancer does not have symptoms until it is quite advanced. For this reason, it is important for women to get screened regularly for cervical cancer. Other less common HPV-related cancers, such as cancers of the vulva, vagina, anus and penis, also may not have signs or symptoms until they are advanced.

To attain the greatest impact on cervical cancer prevention, the ACS provides the following supporting recommendations:
1.) Screening:
--It is critical that women, whether vaccinated or not, continue screening according to current ACS early detection guidelines.
--A preventive health care visit in which vaccination is discussed or offered represents an appropriate opportunity to offer Pap screening to sexually active patients.
--HPV testing before initiating vaccination is not recommended.
2.) Vaccine Implementation and Utilization:
--Public health and policy efforts are needed to ensure access and encourage high HPV vaccine coverage for all racial, ethnic, and socioeconomic groups, particularly for females of color, immigrants, those living in rural areas, low-income and uninsured females, and others who have limited access to health care services.
--Strategies should be implemented to maximize adherence to vaccination recommendations, including coadministration with other recommended adolescent vaccines, once sufficient safety data are available.
--The use of noncomprehensive visits (eg, minor illness visits, camp/sports physical visits) and alternative vaccination sites for adolescents unable to access comprehensive preventive care is encouraged.
3.) Education:
--There is a critical need for education of providers, policy-makers, parents, adolescents, and young women about cervical cancer prevention and early detection, including the need for regular screening even after vaccination.
4.) Research:
--Ongoing research and surveillance should be conducted in diverse populations, including research on duration of protective immunity, population- and lesion-based changes in type-specific prevalence for the full spectrum of carcinogenic and noncarcinogenic genital HPV types, changes in Pap test performance characteristics, changes in screening practices and behaviors, comprehensive surveillance for reproductive toxicities, increasing vaccine coverage and acceptability, and impact on safe sexual behavior.
--Safety and efficacy of prophylactic HPV vaccine for the prevention of other anogenital cancers and head and neck cancers in males, as well as females, should be evaluated.
--Research is needed regarding the design of sustainable vaccination programs in less developed countries.

According to the CDC, there are important steps girls and women can take to prevent cervical cancer. The HPV vaccine can protect against most cervical cancers. Cervical cancer can also be prevented with routine cervical cancer screening and follow-up of abnormal results. The Pap test can identify abnormal or pre-cancerous changes in the cervix so that they can be removed before cancer develops. An HPV DNA test, which can find high-risk HPV on a woman’s cervix, may also be used with a Pap test in certain cases. The HPV test can help healthcare professionals decide if more tests or treatment are needed. Even women who got the vaccine when they were younger need regular cervical cancer screening because the vaccine does not protect against all cervical cancers. Unfortunately, there is currently no vaccine licensed to prevent HPV-related diseases in men. Studies are now being done to find out if the vaccine is also safe in men, and if it can protect them against HPV and related conditions. The FDA will consider licensing the vaccine for boys and men if there is proof that it is safe and effective for them. There is also no approved screening test to find early signs of penile or anal cancer. Some experts recommend yearly anal Pap tests for gay and bisexual men and for HIV-positive persons because anal cancer is more common in these populations. Scientists are still studying how best to screen for penile and anal cancers in those who may be at highest risk for those diseases.

In the United States, each year it is estimated that over 6 million people are infected with genital HPV, according to the American Cancer Society (ACS). An estimated 20 million people in the United States, approximately 15% of the population, are currently infected as detected by HPV DNA assays. Almost half of the infections are in those aged 15 to 25 years. Point prevalence estimates for young women range from 27% to 46%. At least half of all sexually active men and women acquire HPV at some point in their lifetime, and modeling studies suggest that up to 80% of sexually active women will have become infected by age 50. There have been some concerns that the perception of safety resulting from introduction of a prophylactic HPV vaccine will lead to an increase in unsafe behaviors and premature sexual activity among adolescents ("behavioral disinhibition").

Some organizations have expressed their support for universal availability of HPV vaccines while emphasizing that vaccination should not be a substitute for sexual abstinence until marriage and fidelity after marriage as reported by the ACS. Media coverage has cited such concerns as a potential barrier to vaccine acceptance and implementation, and several small studies also have cited this as a barrier to parental and provider acceptability. Historically, similar concerns have been raised with regard to penicillin for syphilis, condom availability programs, and emergency contraception. Knowledge of HPV also varies among health care providers. Pediatricians and primary care providers may have limited familiarity with and understanding of HPV, whereas gynecologists may have greater understanding of HPV infection, regression, persistence, and progression to cervical cancer precursors.

Vaccinating against HPV is still a controversial issue. One consensus is that abstinence until marraige may be the best way to prevent contracting the disease in most cases. Another view is that vaccinations should be given to all girls starting at certain ages just as a purely preventive measure regardless of their personal home situation. Mandating vaccinations for HPV should be avoided, as it is not a disease that can be contracted by innocent contact with someone who has a disease such as measles or other communicable illnesses. Studies of patients who have been vaccinated are not entirely conclusive that there are no side effects or long term problems from receiving the medication to prevent HPV. The best way to maintain a healthy life and avoid HPV altogether is to wait until marraige before sleeping with someone and avoid sexual contact with anyone other than a monogomous heterosexual spouse.

Until next time. Let me know what you think.

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