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Study shows HPV vaccine lowers HPV infection risk in teen girls

conservative-HPV-vaccineHPV quadrivalent vaccine, also known as Gardasil (or Silgard in Europe), is marketed by Merck, usually for vaccination of teenage girls (with an increasing number of boys). The vaccine prevents the transmission of certain types (pdf) of human papillomavirus (HPV), specifically types 6, 11, 16 and 18. HPV types 16 and 18 cause approximately 70% of cervical cancers, and caused most HPV-induced anal (95% linked to HPV), vulvar (50% linked), vaginal (65% linked), oropharyngeal (60% linked) and penile (35% linked) cancers. These cancers, mostly related to HPV, can be prevented as long as you can prevent the HPV infection from ever happening, which usually happens through genital contact, most often during vaginal and anal sex. HPV may also be passed on during oral sex and genital-to-genital contact. HPV can be passed on between straight and same-sex partners—even when the infected partner has no signs or symptoms. Approximately 79 million Americans, most in their late teens and early 20’s, are infected with HPV, and about 14 million people become infected each year in the USA.

According to CDC, each year in the United States, about 19,000 cancers caused by HPV occur in women, and cervical cancer is the most common.  About 8,000 cancers caused by HPV occur each year in men in the United States, and oropharyngeal (throat) cancers are the most common.

A new study, published in the June issue of The Journal of Infectious Diseases examined the prevalence HPV infections in girls and women before and after the introduction of the HPV vaccine, concluded that after the introduction of the vaccine, there was a significant reduction in HPV types targeted by the vaccine (HPV-6, -11, -16, and -18). The study revealed that since the vaccine was introduced in the USA in 2006, the prevalence of the HPV types prevented by the vaccine decreased by 56% among female teenagers, 14-19 years old.

According to CDC Director Tom Frieden, MD, MPH, “This report shows that HPV vaccine works well, and the report should be a wake-up call to our nation to protect the next generation by increasing HPV vaccination rates. Unfortunately only one third of girls aged 13-17 have been fully vaccinated with HPV vaccine. Countries such as Rwanda have vaccinated more than 80 percent of their teen girls. Our low vaccination rates represent 50,000 preventable tragedies – 50,000 girls alive today will develop cervical cancer over their lifetime that would have been prevented if we reach 80 percent vaccination rates.  For every year we delay in doing so, another 4,400 girls will develop cervical cancer in their lifetimes.”

Rwanda has 80% vaccination rates for HPV, and the USA only 33%? We know who to blame for this.

Back to the results:

  • The study compared HPV prevalence in 4,150 females in 2003-2006 (before introduction of the vaccine) and in 4,253 females from 2007-2010.
  • The study used the National Health and Nutrition Examination Survey (NHANES) data to compare prevalence—or proportion of girls and women aged 14-59 years with certain types of HPV—before the start of the HPV vaccination program (2003-2006) with the prevalence after vaccine introduction (2007-2010). 
  • The incidence of HPV (prevented by the vaccine) dropped from 11.5% to 5.1%, a decrease of 56% (all numbers are statistically significant at a 95% confidence interval).
  • Of the the 2007-2010 group, 34.1% had at least 1 vaccination (and of those, 62.5% had all three).
  • Sexual behavior between the two groups was insignificantly different, with 53.9% having had sex in the 2003-2006 group, and 50.3% in the 2007-2010. There were no significant differences between the groups in lifetime number of partners and race/ethnicity.

“The decline in vaccine type prevalence is higher than expected and could be due to factors such as to herd immunity, high effectiveness with less than a complete three-dose series and/or changes in sexual behavior we could not measure,” said Dr. Markowitz. “This decline is encouraging, given the substantial health and economic burden of HPV-associated disease.” 

With these better than expected results regarding the effectiveness of the vaccination along with the outstanding safety profile as shown in massive epidemiological studies (approximately 200,000 women), why would any parent not get their daughters (and to be honest, sons too) vaccinated with the HPV vaccine. All three doses. It saves lives, thousands of lives. 

Get your sons and daughters vaccinated with the HPV vaccine. Do it. Because Gardasil saves lives.

 

Use the Science-based Vaccine Search Engine.

 

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