Human papillomavirus (HPV) is the most commonsexually transmitted infection in the US. There are more than 150 types of HPV, 40 of which can be contracted through skin-to-skin contact during vaginal, anal or oral sex.
Low-risk HPV types, such as HPV-6 and HPV-11, can cause warts around the genitals or anus. But high-risk types, including HPV-16 and HPV-18, account for approximately 5% of all cancers worldwide.
Specifically, HPV-16 and HPV-18 account for around 70% of all cervical cancers and almost 50% of all vaginal, vulvar and penile cancers. HPV-16 is also accountable for more than 50% of throat cancers.
There are currently two vaccines available for HPV, which are administered in three shots over 6 months. Cervarix and Gardasil are used for the prevention of cervical cancer, while Gardasil can also protect against anal, vulvar and vaginal cancers and genital warts.
The Advisory Committee on Immunization Practices (ACIP) recommends that preteen girls and boys aged 11 or 12 are vaccinated against HPV. The vaccination is also recommended for teenage girls and young women up to the age of 26 who did not receive it when they were younger, and teenage boys and young men up to the age of 21.
HPV vaccination coverage increased in 2012-13, but remains too low
But despite these recommendations, a new report from the Centers for Disease Control and Prevention (CDC) – published in this week’s Morbidity and Mortality Weekly Report – estimates that in 2013, only 57% of girls and 35% of boys ages 13-17 years received one or more doses of the HPV vaccine.
The figures came from results of the CDC’s National Immunization Survey-Teen (NIS-Teen), which includes vaccine information via telephone surveys for adolescents aged 13-17 years from across the US.
The CDC investigators did, however, find that HPV vaccination coverage increased slightly among girls between 2012-13, from 53.8% to 57.3%, although only a third received the complete three doses. Teenage boys saw a greater increase in vaccination coverage, from 20.8% to 34.6%.
But still, the CDC say HPV vaccination coverage among adolescents is too low, particularly when compared with coverage to other vaccination types. For example, another report from the CDC found that almost 86% of adolescents received one dose of the Tdap vaccine last year, which protects against tetanus, diphtheria and whooping cough.
A 10-year national objective in the US – set in 2010 by Healthy People 2020 – is to reach 80% HPV vaccination coverage among adolescents. These latest statistics suggest there is a lot of work to be done. But according to Dr. Anne Schuchat, assistant surgeon general and director of the CDC’s National Center for Immunization and Respiratory Diseases, they also show promise:
“It’s frustrating to report almost the same HPV vaccination coverage levels among girls for another year. Preteens need HPV vaccine today to be protected from HPV cancers tomorrow.
The high coverage rate of Tdap vaccine shows us that it is certainly possible to reach our goal of vaccinating 80% of adolescents against cancers caused by HPV.”
Why is HPV vaccination coverage still low?
From NIS-Teen, the CDC investigators were also able to establish some reasons as to why HPV vaccination coverage remains low among adolescents.
They found that clinicians’ recommendations significantly influenced a parent’s decision of whether to have their children vaccinated against HPV.
Fast facts about HPV
- Approximately 79 million Americans are infected with HPV
- Around 14 million Americans are newly infected with HPV every year
- Almost all sexually active men and women contract HPV throughout their lifetime, but many are unaware they have it.
Of parents whose daughters were vaccinated, 74% said they received a recommendation from their doctor, while 52% of parents who did not have their daughters vaccinated received a doctor’s recommendation. Among parents whose sons were vaccinated, 72% received a recommendation, while only 26% of parents whose sons were not vaccinated received a recommendation.
Based on these findings, Dr. Schuchat believes health care professionals are key in boosting HPV vaccination coverage among adolescents in the US.
“Pediatricians and family physicians are uniquely situated to prevent missed opportunities by giving HPV vaccine during the same visit they give Tdap and meningococcal vaccines,” she adds.
The CDC state that if preteen girls had received the HPV vaccine with other vaccines during health care visits in the year 2000, vaccination coverage in this cohort could have reached 91.3%.
Parents also revealed that concerns over the safety of the HPV vaccine deterred them from vaccinating their children. However, the CDC stress that – after analyzing national postlicensure vaccine safety data – no serious safety concerns have been linked to the HPV vaccine in the 8 years it has been available.
The investigators point out that the most commonly reported side effects of the vaccine include dizziness, fainting, nausea and headache, and injection-site reactions – including pain, redness and swelling.
In conclusion to the report, the CDC say they will continue efforts to team up with state and local immunization programs, cancer organizations, professional organizations and other stakeholders in an attempt to educate parents and health care professionals about the importance of the HPV vaccine, adding:
“Collaborative efforts remain critical to promoting HPV vaccination so that the nation’s adolescents are protected against vaccine-preventable, HPV-associated cancers.”