HPV: To vaccinate or not to vaccinate?
Human papillomavirus (HPV) is a common virus that is typically spread by skin-to-skin contact during sexual activity. Certain types of HPV can cause cancer. The first vaccine to protect against certain types of HPV, Gardasil®, was introduced in 2006 and a second vaccine, Cervarix®, followed in 2009.
Today, HPV vaccination is recommended as part of the routine immunization schedule for boys and girls aged 11 or 12, with catch-up vaccination recommended for those 13-26 years old.
The HPV vaccine has been controversial in the U.S. since it was introduced because of a fear that vaccination might encourage girls to engage in sexual activity at a young age. More recently, parents also have expressed concerns about the safety of the vaccine.
A recent survey showed that 16.4 percent of parents in 2010 did not plan to have their daughter immunized because of concerns about safety and side effects. In 2008, it was 4.5 percent.
Health officials and physicians have offered several explanations for the low vaccination rate among teen girls, including inconsistent information from doctors who don’t always suggest the vaccine because of insurance or ethical concerns. Here are some facts about HPV vaccination to help families make a more informed decision.
What’s the difference between the two vaccines and who should get them?
Both Gardasil and Cervarix are effective against HPV types 16 and 18, which cause most cervical cancers. Both vaccines have been shown to prevent cervical precancers in women. To protect against cervical cancer, either vaccine is recommended for girls at 11 or 12 years old. Teenage girls and young women ages 13-26 are advised get the HPV vaccine if they did not receive any or all doses when they were younger.
Only Gardasil has been tested and licensed for males. Gardasil is recommended for boys aged 11 or 12 years, and for males 13-21 years old, who did not get any or all of the three recommended doses when they were younger. All men may receive the vaccine through age 26.
The vaccine is also recommended for gay and bisexual men, any man who has sex with men and men with compromised immune systems through age 26, if these men did not get fully vaccinated when they were younger.
What are the vaccine risks?
Side effects of the HPV vaccines are similar to other vaccines, and may include fainting, dizziness, nausea, headache, fever and hives. Pain, swelling, itching, bruising and redness at around the injection also can occur.
Some parents may be concerned about media reports of young girls who’ve died after being vaccinated. The Centers for Disease Control and Prevention (CDC) has investigated 42 reports of deaths among HPV vaccine recipients, finding that the cause of death varied from cardiovascular to infectious. CDC officials concluded the vaccine was not responsible for those 42 deaths.
The benefits of ‘herd immunity’
The good news is that while only one-third of teenage girls have received the full course of HPV vaccine, the prevalence of HPV strains that cause cervical cancer has fallen by more than half among all teen girls. The steep decrease comes despite the United States having one of the lowest HPV vaccination rates among developed countries. The concept of herd immunity could be at work. Herd immunity occurs when a critical portion of a community is immunized against a contagious disease, and those who have not been vaccinated are protected.
Vaccination is driving the recent decrease in HPV. In 2006, the year Gardasil was introduced, the infection rate with HPV strains targeted by the vaccine was 11.5 percent among 14- to 19-year-old girls. By 2010, the rate was cut to 5.1 percent, a 56 percent decrease, according to a national survey of teen girls reported in The Journal of Infectious Diseases in June.
In addition, partial dosage is a safeguard. Just one dose of the vaccine was found to be 82 percent effective against HPV. Almost half of teen girls have received at least one dose of HPV vaccine.