On immunizing teenagers

August 1, 2007

Q and A with Alain Joffe, MD about current recommendations for adolescent vaccinations.

Q: Dr. Joffe, pediatricians and parents are used to thinking about immunization as an essential aspect of preventive health care for infants and toddlers. Now we're being asked to change that perspective, to think of immunization as something we also do for adolescents. How come?

A: Two reasons: Evidence like the resurgence of pertussis and breakthrough varicella-that the immunity conferred by the shots given in infancy wanes over time. And life cycle events like sexual debut and college entry-that make teenagers especially vulnerable to certain diseases.

Q: What vaccines are we talking about?

Tdap (Adacel, Boostrix), replacing Td in earlier schedules. Tdap adds acellular pertussis vaccine to the tetanus and diphtheria vaccines teens have been getting, to protect them against the recent resurgence in pertussis. Adolescents who are infected with pertussis are a serious danger to very young infants who aren't fully immunized, and they themselves can be miserably ill with this disease.

HPV (Gardasil), appears to confer close to 100% effectiveness against the two serotypes of human papillomavirus (HPV) that cause most cases of cervical cancer. There is no evidence that immunizing girls against a sexually transmitted infection like HPV leads to more or earlier sexual activity, but there is some legitimate opposition to making this vaccination mandatory for school entry.2

MCV4 (Menactra), a highly effective conjugate vaccine that offers protection against most strains of meningococcal meningitis. This is a devastating disease that terrifies any community where it breaks out.

Q: Are there more recommendations for teens?

A: Yes. There are catch-up recommendations for teens who missed immunizations when they were younger. These include MMR (measles, mumps, rubella); varicella (Varivax), except for teens who've had two doses of vaccine or a documented case of the disease; hepatitis B, important for teens especially because it's transmitted by sex and IV drug use; and IPV (inactivated polio vaccine). And for teen populations living where the risk is high, hepatitis A (Havrix, Vaqta). Finally, PPV (pneumococcal polysaccharide vaccine). and influenza for certain high-risk groups.

Q: The routine immunizations are recommended for the 11- to 12-year visit. Why pick that age?

A: A visit for that age group has been in place for quite some time, and parents have come to expect it. Older teens tend to drop out of the system; they are much harder to get into the pediatrician's office. At 11 to 12, kids are going off to middle schools, which usually require proof of immunization for entrance. And because HPV is a sexually transmitted infection, the Gardasil recommendation is intended to provide protection when it is most effective, before the onset of sexual activity.

Q: How would you rate the success of this push for immunizing teens?

A: It's really too soon to say. This is a whole new playing field. It's going to take time to get into the mindset of pediatricians that they need to do it, and it's also going to take time for parents and the public generally to recognize that these new vaccines will prove to be of tremendous benefit to adolescents.

Q: But as you've said, many older teens don't come into the pediatricians' office at all. How are we going to get them fully immunized?

A: Our primary emphasis must continue to be on doing immunizations in the medical home, the place where the pediatric caregiver knows the teen best, keeps the immunization record, and can use the occasion to deal with other adolescent issues as well.

But having said that, we know that many families lose their health insurance or have to change providers when they change insurance, and that some providers may not offer the costly new vaccines. The critical thing is for adolescents to get the vaccines they need.