Winning the War against Cervical Cancer

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Winning the War against Cervical Cancer
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Winning the War against Cervical Cancer

I've yet to meet anyone who loves cancer. When President Nixon began the war on cancer in 1971 with the signing of the National Cancer Act, it was intended to "...strengthen the National Cancer Institute in order to more effectively carry out the national effort against cancer." Despite the billions of dollars spent, and a few scattered victories (e.g. childhood leukemia) the casualties continue to mount in this 40 year campaign with no end in sight.

Diseases such as smallpox and polio have both succumbed to our relentless attack with vaccines, yet cancer has largely remained immune to our assaults. We are not winning this war.

If only we had a vaccine that held the power to vanquish this scourge. We actually do. The problem is that hardly anybody is using it.

In 2006 the pharmaceutical company Merck won approval for Gardasil(R), the first vaccine designed to block the transmission of Human Papillomavirus (HPV). HPV is a family of several closely related viruses, all of which are spread through sexual contact and may cause genital warts. While most HPV infections do not produce symptoms, in some cases of persistent infection the virus can go on to cause cancer.

Most cervical cancers are caused by HPV. Before the HPV vaccine the most effective intervention was annual PAP smears followed by aggressive treatment in the case of a positive diagnosis. With a five year survival rate of less than 16% for stage 4 cervical cancer the odds are not good and despite our best efforts cervical cancer still claims nearly 4000 American women every year.

The HPV vaccine effectively blocks the transmission of those viral strains that cause most cervical cancers. Despite the obvious benefits, in some states fewer than 25% of adolescent girls have received the three doses of the HPV vaccine needed to protect them from the trauma of this terrible disease. Nationwide fewer than 35% of mothers approve of protecting their teenage daughters, and support for vaccination is actually dropping.

Some of this opposition can be attributed to a general distrust of vaccines. A fraudulent 1998 study by Andrew Wakefield allegedly linked autism in children to the widely used MMR vaccine. Numerous studies have since demonstrated that there is no such connection to autism. Yet thousands of Americans refuse to vaccinate their kids in the mistaken belief that they are protecting their children when in fact they are endangering them. Likewise rumors have circulated about severe reactions to the HPV vaccine, but in 2012 the Centers for Disease Control looked into these claims and found that there are no serious side effects with the HPV vaccine.

Another objection stems from the fact that in order to confer protection the vaccine should be administered before a person becomes sexually active. For this reason it is recommended that girls be vaccinated before their thirteenth birthday. Some parents operate under the mistaken belief that by vaccinating their daughters they are inadvertently sanctioning teen sex. In 2012 Emory University researchers, who had followed over 1000 girls for several years, showed that sexual activity of vaccinated girls was absolutely no different from those who were not protected from this deadly virus.

These data were so compelling that Texas Governor Rick Perry signed an executive order requiring all 12-year old girls be vaccinated against HPV, a position for which he was ridiculed in a presidential primary debate. But an Australian study that came out this year shows that Governor Perry was absolutely right.

Australia has had a mandatory HPV vaccine program for several years. Using the prevalence of genital warts as a proxy for measuring infection Australian health officials have seen not only a dramatic drop in HPV infections in girls but also in boys. HPV can only be spread from one infected person to an uninfected one. As fewer girls contract the virus there are less infected boys. The CDC now recommends the HPV vaccine for boys as well as girls. Australia is already doing this.

Decades from now women in Australia and Texas will reap the benefits of these policies, free from the fear of this dread disease. Likewise a growing number of mouth and oral cancers in males that are also linked to HPV will become but a memory.

If we have a weapon that can defeat cancer for present and future generations, what are we waiting for?

Images: Jan Christian, CDC.

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