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Monday, September 1, 2008

The HPV Vaccine: Risks, Benefits and Alternatives

In June 2006 the United States Food and Drug Administration (FDA) approved the Gardasil® vaccine, designed to prevent infection by certain strains of the human papillomavirus (HPV). That same month, a federal advisory panel on immunization practices recommended that all eleven and twelve year old girls receive the vaccine. But before girls and their parents can make informed decisions, it is important to understand the possible risks and potential benefits of Gardasil®, as well as alternative options for increasing immunity and reducing risk of infection.

Human Papillomavirus and Cervical Cancer

There are more than one hundred strains of the human papillomavirus and at least forty can be transmitted through sexual contact to both men and women. According to the National Cancer Institute, fourteen of these sexually-transmitted HPV strains have been associated with a high risk for developing cervical cancer. Two of these, 16 and 18, are associated with seventy percent of all cases.

According to the FDA, HPV infection is very common and it is rare for HPV infection to lead to cervical cancer, especially in women under the age of thirty. In fact, ninety percent of cervical HPV infections become undetectable within two years. When cervical cancer is diagnosed, it is one of the most treatable cancers. According to the American Cancer Society, invasive cervical cancer diagnosed in its earliest stage has a five-year survival rate of ninety-two percent.

Immunization Basics

Gardasil®, manufactured by Merck, is currently the only available vaccine against HVP, specifically strains 6, 11, 16 and 18. To measure the effectiveness of the vaccine, trials conducted by Merck assessed prevention of pre-cancerous lesions, not cervical cancer. Therefore, predictions about the ability of Gardasil® to prevent cancer is speculation, as the majority of pre-cancerous lesions revert to normal without treatment and only a minority develop into cancer.

Merck researchers concluded that the vaccine was ninety-nine percent effective in preventing infection and pre-cancerous lesions caused by HVP strains 6, 11, 16 and 18 in women who had not been exposed to these viruses before immunization. The vaccine did not protect against infection or pre-cancerous lesions in women who had already been exposed to HPV. Because more than half of all men and women are exposed to HPV within one year of becoming sexually active, the vaccine is most effective when administered before the onset of sexual activity.

According to the CDC, approximately thirty percent of cervical cancers are caused by HPV strains not covered by Gardasil® and women who receive the vaccine are still at risk for cervical cancer. The vaccine does not treat existing HVP infections and does not prevent cervical cancer caused by existing infections.

The vaccine has only been tested by Merck, only for four years, and only in girls and women between the ages of nine and twenty-six. There is no long-term safety data about the vaccine and no information about its use in girls less than nine years old and in women above the age of twenty-six.

Certain individuals should not receive the Gardasil® vaccine. These include women who are pregnant or may become pregnant, breastfeeding women and anyone with a compromised immune system resulting from immunosuppressive therapy, genetic defects, human immunodeficiency virus (HIV) or acquired immune deficiency syndrome (AIDS).

Adverse Effects

According to Merck’s clinical data, adverse effects after immunization most commonly included pain and inflammation at the injection site, fainting, dizziness, fever and nausea. Other side effects were rare but some were very serious, including blood clots, lymphatic system disorders, gastrointestinal problems, nervous system disorders such as Guillain-BarrĂ© Syndrome, musculoskeletal and connective tissue problems, systemic autoimmune disorders such as rheumatoid arthritis, juvenile arthritis and systemic lupus erythematosis and death. Cases of paralysis have also been reported.

According to Merck, Gardasil® has not been studied for its potential to cause cancer or birth defects. However, during clinical trials, women who became pregnant within thirty days of receiving the vaccine had more “serious adverse experiences during pregnancy” including “congenital abnormality” compared to women who received a placebo. Additionally, cases of acute respiratory illness were higher in the infants of breastfeeding women who had received the vaccine within the previous thirty days, compared to infants of breastfeeding women who received the placebo.

One additional concern is the aluminum contained in the vaccine. Aluminum is a heavy metal that can accumulate in the body and has been associated with disruption of normal neurological function. Elevated levels of aluminum have been associated with dyslexia, Alzheimer’s disease and amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder also known as Lou Gehrig’s disease.

Risky Behavior

One alternative to the HVP vaccine is behavior modification. Because HPV strains 6, 11, 16 and 18 are transmitted by sexual contact, abstinence from sexual activity is one hundred percent effective in preventing infection and associated pre-cancerous lesions. When abstinence is not realistic, other behaviors can reduce the risk: delaying the onset of sexual activity, reducing the number of sexual partners and using condoms during sexual activity. Condoms can reduce transmission of the human papillomavirus, but only to and from the areas they protect: the cervix, vagina, penis, anus, and rectum. Condoms do not prevent HVP transmission to and from other areas, including the vulva and perineum.

Regular Screening

Because HPV has a slow growth cycle, most associated cases of cervical cancer are slow to develop and slow to progress. For this reason, regular Papanicolaou tests, also known as pap smears, are important tools of prevention. Pap smears can catch cellular abnormalities that may lead to cancerous changes before they occur and detect early stages of cancer while still highly curable. An additional HPV test, administered at the same time as the Pap test, can determine if a woman has been infected with a high-risk strain. As a result of regular testing, the death rate from cervical cancer continues to drop approximately four percent every year.

Girls and women who are immunized with Gardasil® still require regular pap smears because the vaccine does not protect against all HPV strains associated with cervical cancer, nor does it protect against other causes, including genetic defects and exposure to carcinogenic compounds in cigarette smoke.

Probiotics

Probiotics are healthy bacteria that can prevent infection by other microorganisms. When taken by mouth, they reduce the risk of viral gastrointestinal (GI) infections and vaginal yeast infections. Because they promote a healthy balance of flora in both the vagina and GI tract, probiotics taken orally may reduce susceptibility to HPV infection of the vulva, vagina, cervix, perineum, anus and rectum,. They may also reduce the risk of HPV-associated cervical cancer. Probiotics are available in supplement form, but regular consumption of organic plain yogurt and kefir are also good sources.

Lifestyle Factors

A healthy lifestyle is essential. Getting regular exercise and eating a healthy diet can prevent cancer as well as chronic disease. Studies have consistently shown that people who eat the most fruits and vegetables have the lowest rates of cancer and researchers continue to learn more about the vital role that nutrients found in plant foods play in prevention. Phytonutrients can increase the elimination of carcinogenic compounds from the body, protect cells against damage to DNA and inhibit the growth and development of cancerous cells.

Also essential to a healthy lifestyle is addressing stress and high blood sugar. Both of these conditions can suppress the immune system and inhibit the action of white blood cells responsible for destruction of viruses like HPV and abnormal or cancerous cells in the body. Blood sugar imbalances should be discussed with a doctor and are often treatable through diet and exercise. Stress management strategies are plentiful, from meditation and breathing exercises to yoga, tai chi and qi gong.

Nutritional supplements and botanical medicines can also support a healthy immune system and help prevent cancer. Never self-prescribe; instead find a doctor trained in the use of these natural therapies to individualize a protocol for you. She or he will take into account your medical history, risk factors, current symptoms, future goals and any potential interactions with medications or supplements you may already be taking.