August 18, 2014
News Review From Harvard Medical School -- Shots Fight Cancer-Linked Virus 8 Years
A vaccine appears to protect against human papillomavirus (HPV) for 8 years, a new study finds. Human papillomavirus causes most cases of cervical cancer. This was a long-term follow-up to an earlier study. In the original study, more than 1,700 boys and girls were randomly assigned to receive the vaccine or placebo shots. Those who received the placebo were given the actual vaccine 2½ years later. Researchers called this the catch-up group. In the first group, the average child was 12 when vaccinated. In the catch-up group, the average age was 15. Each person received 3 doses. Researchers were able to keep track of more than 1,600 of the original study group. This included 1,100 from the first vaccination group. After up to 8 years (average 6.8), the vast majority of this group had blood antibodies against HPV. No one in the early vaccination group developed a lasting HPV infection. There were 7 cases of lasting infection in the catch-up group. Researchers said they may have been infected before getting the vaccine. The journal Pediatrics published the study. HealthDay News wrote about it August 18.
By Henry H. Bernstein, D.O., M.H.C.M.
Harvard Medical School
What Is the Doctor's Reaction?
The human papillomavirus (HPV) is an infection easily passed during sex. More than half of sexually active people get it at some point in their lives. For most people, the infection goes away on its own. But in some cases, HPV causes cancer. For example, about 11,800 U.S. women were diagnosed with cervical cancer in 2010. About 3,900 died of the disease.
The HPV vaccine helps prevent serious health problems caused by HPV infection, such as:
- Cervical and anal cancer in females
- Head, neck, penile and anal cancer in males
- Genital warts in females and males
- Warts in the airways of babies and children
A study in the journal Pediatrics looked to see if the HPV vaccine is still helpful as much as 8 years after the first dose. The researchers kept track of more than 1,600 boys and girls who got a 3-dose series of the HPV vaccine. They received the shots between ages 9 and 15.
The study checked how well the vaccine offered them:
- Immunity (amount of protection)
- Effectiveness (cases of HPV infection or disease prevented)
- Safety (cases of serious side effects from getting vaccine)
One group got the vaccine at an average age of 12 years. For the "catch-up" group, the average age was 15. Researchers found that:
- Children and teens were protected from HPV as long as 8 years after vaccination.
- Not one teen in the early-vaccination group developed a serious HPV-related infection or disease.
- Three serious health events occurred during the study period. One was related to the vaccine.
- The only cases of serious HPV infection that occurred were found in the catch-up vaccination group. In one case, abnormal cervical cells were found. This could be because this group was vaccinated three years later than the other group. They might have been exposed to HPV sometime in those years before getting the vaccine.
The authors believe that HPV vaccine has an important role in preventing HPV-related cancers. This study's long-term data on effectiveness and safety should be very reassuring to teens, families and health care professionals. I hope that more teens and families now will accept the HPV vaccine.
What Changes Can I Make Now?
It's important to get your sons and daughters vaccinated to protect them against HPV. The American Academy of Pediatrics and Centers for Disease Control and Prevention recommend HPV vaccine for all males and females at ages 11 to 12. The vaccine is licensed for children as young as age 9.
There are 2 HPV vaccines. Gardasil (HPV4) is recommended for both females and males. Cervarix (HPV2) is recommended only for females. Both are given as 3 shots over a 6-month period.
The HPV vaccine prevents cancer. Yet some parents hesitate to have their young children vaccinated against a virus that is spread through sex.
Your child should not wait until he or she is sexually active to get the HPV vaccine. The vaccine works best when it is given before someone has sex for the first time. Plus, this study shows us that the HPV vaccine keeps working as much as eight years after the vaccine series was received.
What Can I Expect Looking to the Future?
Expect doctors to routinely recommend the HPV vaccine for your children by age 11. Do not delay getting the vaccine for your children. If you have any concerns about the HPV vaccine, talk with the pediatrician.
I hope that, with better education, more parents will get all their children vaccinated against HPV. The best timing for the vaccine to protect against cancer is before your child begins having sex.
I expect that more children will get the HPV vaccine when they are younger. This will lead to less cancer. Many more lives will be saved.