The Advisory Committee on Immunization Practices voted Wednesday, 14-0 with one abstention, to recommend that a tetanus-diphtheria-acellular pertussis booster vaccine be given to pregnant women during each pregnancy, despite concern over the lack of data for the safety of multiple Tdap vaccinations.
Last year, ACIP recommended that pregnant women receive the Tdap vaccine only if they have previously not received one.
In a Vaccine for Children vote, the committee voted unanimously to include a change that recommends that adolescents who are pregnant should receive a dose of Tdap, regardless of their Tdap vaccination history.
“There is absolutely no question that we need more data,” Carol Baker, MD, professor of pediatrics at Baylor College of Medicine, said while representing the IDSA at the meeting. “But we have to consider risk to the mother vs. the benefit, just like this committee always has.”
According to Jennifer Liang, MD, epidemiologist in the CDC’s National Center for Immunization and Respiratory Diseases, antibody response from the Tdap vaccine peaks at 1 month after vaccination and decreases significantly after 1 year. Because of this, women who have received the vaccine during a previous pregnancy may not have the same protection at future pregnancies.
“A single dose of Tdap at one pregnancy is insufficient to provide protection for subsequent pregnancies,” Liang said.
A lack of safety data about multiple Tdap vaccinations caused some hesitancy among the committee, especially when considering women who have short intervals between pregnancies. There are no data available that address this specific issue, but available data suggest that there is no excess risk of adverse events, Liang said, adding that the CDC working group supports the need for a prospective study to determine the adverse event risk in women with multiple pregnancies.
She said data indicate that the average woman has two children, and most have an interval of at least 13 months between pregnancies, meaning that most women would not receive more than two doses of the vaccine.
After recommendations, the ACIP continues to review data about its recommendations and will continue reviewing data on the safety of giving multiple Tdap vaccinations to pregnant women.
Because the recommendation is an off-label use of the Tdap vaccine, there was concern about whether insurance programs, including Medicare and Medicaid, would cover the vaccinations for these women.
“In making an off-label use recommendation, what we need to understand is how the coverage of immunizations under Medicare and Medicaid and individual insurance plans will be affected,” committee member Sara Rosenbaum, JD, said.
A representative from American’s Health Insurance Plans (AHIP) indicated that insurance plans almost always follow ACIP recommendations, even when those recommendations are for off-label use, and there is precedent for it. A representative for the CMS indicated that, for Medicaid, the ACIP recommendations are followed, but for Medicare, ACIP recommendations are not followed under Part D.