While the controversy over the HPV vaccine may continue in some circles, a new study says the vaccine is proving effective in teenage girls.
The human papillomavirus (HPV) vaccine was introduced 10 years ago and its use immediately became a hot topic. The vaccine is recommended for young girls and boys ages 11 and 12, to protect them from the sexually transmitted virus that can cause cervical as well as anal, penile, mouth and throat cancers.
The study found that in teenage girls, the virus’s prevalence has been reduced by two-thirds.
Even for women in their early 20s, a group with lower vaccination rates, the most dangerous strains of HPV have still been reduced by more than a third.
“We’re seeing the impact of the vaccine as it marches down the line for age groups, and that’s incredibly exciting,” said Dr. Amy B. Middleman, the chief of adolescent medicine at the University of Oklahoma Health Sciences Center, who was not involved in the study. “A minority of females in this country have been immunized, but we’re seeing a public health impact that is quite expansive.”
HPV vaccinations rates, in young girls and boys, have slowly been increasing, since the vaccine was introduced, but 4 out of 10 adolescent girls and 6 out of 10 adolescent boys have not started the recommended HPV vaccine series, leaving them vulnerable to cancers caused by HPV infections.
That is partly because of the implicit association of the vaccine with adolescent sexual activity, rather than with its explicit purpose: cancer prevention. Only Virginia, Rhode Island and the District of Columbia require the HPV vaccine.
The latest research examined HPV immunization and infection rates through 2012, but just in girls. The recommendation to vaccinate boys became widespread only in 2011; they will be included in subsequent studies.
Using data from a survey by the Center for Disease Control and Prevention (CDC), the study examined the prevalence of the virus in women and girls of different age groups during the pre-vaccine years of 2003 through 2006. (The vaccine was recommended for girls later in 2006.) Researchers then looked at the prevalence in the same age groups between 2009 and 2012.
By those later years, the prevalence of the four strains of HPV covered by the vaccine had decreased by 64 percent in girls ages 14 to 19. Among women ages 20 to 24, the prevalence of those strains had declined 34 percent. The rates of HPV in women 25 and older had not fallen.
“The vaccine is more effective than we thought,” said Debbie Saslow, a public health expert in HPV vaccination and cervical cancer at the American Cancer Society. As vaccinated teenagers become sexually active, they are not spreading the virus, so “they also protect the people who haven’t been vaccinated,” she said.
Many doctors are pressing for primary care providers to strongly recommend the HPV vaccine in tandem with the other two that preteen children now typically receive.
Many health experts are hoping that the positive results from this study will encourage more pediatricians and primary care physicians to discuss getting the vaccine with parents of young children.
The study was published in the online journal Pediatrics.
Source: Jan Hofman, http://www.nytimes.com/2016/02/22/health/vaccine-has-sharply-reduced-hpv-in-teenage-girls-study-says.html?ref=health