One of the barriers to more effective prevention of invasive meningococcal disease is lack of herd immunity because of insufficient coverage. Only 54% of U.S. 13- to 17-year-olds had received meningococcal vaccine in 2009.
Also, the vaccine’s protective effect appears to be considerably less durable than initially thought. There is mounting evidence of waning immunity by 2-5 years post vaccination. In sum, the evidence suggests that the ACIP’s recommendation at the time of Menactra’s licensure that vaccination routinely occur at the preventive care visit at age 11-12 years "maybe wasn’t the best decision" because it may not protect through the period of highest risk, Dr. Fischer said.
For this reason, this year ACIP has published revised recommendations for the use of meningococcal conjugate vaccines (Menveo and Menactra) in teens, based on a decision made at the fall 2010 ACIP meeting (MMWR 2011;60:72-6). Patients who receive the vaccine at age 11-12 years should get a booster dose at age 16, whereas those who get their first dose at age 13-15 years should have a booster dose at age 16-18. Those who get their first dose at age 16 or later don’t need a booster dose.
The currently available conjugate vaccines cover Neisseria meningitidis serogroups A, C, Y, and W135, but not serogroup B, which predominates among infants. Developing a conjugate vaccine that protects against serogroup B is a high priority. Initial efforts failed because candidate polysaccharide vaccines had molecular mimicry issues predisposing to adverse events. However, several non-polysaccharide vaccines that sidestep such concerns are now in late-stage clinical trials and – if the data prove positive – could be licensed in the next couple of years, according to Dr. Fischer.
Issues of particular interest to primary care physicians that the ACIP is likely to take under consideration within the next year include routine meningococcal conjugate vaccine for infants, hepatitis B vaccine for diabetic adults, and pneumococcal conjugate vaccine for adults, according to Dr. Fischer.
Two additional meningococcal conjugate vaccines are now under Food and Drug Administration review and are likely to be licensed by the end of the year. "I think ACIP is likely to reconsider the issue of routine meningococcal conjugate vaccine for infants in October, with a possible vote on the matter in February," he predicted.
A pneumococcal conjugate vaccine for adults is also likely to be licensed in the coming months, he said. That’s another vaccine the ACIP will consider recommending.
Also on tap for ACIP consideration is the use of human papillomavirus vaccine in males. There’s already a permissive ACIP recommendation for use of the HPV vaccine in males, but since this relatively weak endorsement was issued there have been new data demonstrating the vaccine’s effectiveness in preventing penile cancer, as well as a cost-effectiveness analysis.
Use of the herpes zoster vaccine in 50- to 59-year-olds isn’t recommended by the ACIP at this time. It’s an issue that’s likely to be raised at an upcoming meeting, according to Dr. Fischer.
Routine hepatitis B vaccination in adult diabetic patients as a means of preventing hepatitis outbreaks could come up for a vote as early as ACIP’s October meeting, he said.
Dr. Fischer said he had no relevant financial disclosures.