Vaccines Against Whooping Cough, Tetanus and Diphtheria: The ACIP Recommendations

Before childhood vaccination, the United States averaged 200,752 whooping cough cases and 4,034 deaths a year (1934–1943). Vaccines against pertussis, tetanus and diphtheria changed that — yet pertussis has made a partial comeback, and tetanus still kills people who were never fully vaccinated. CDC has gathered every recommendation of its Advisory Committee on Immunization Practices (ACIP) on these three diseases into one report, approved by the committee in October 2016. It added nothing new; it replaced all earlier reports as a single reference for clinicians.

The vaccines

From the late 1940s through the 1990s children got DTP, with whole-cell pertussis, which often caused redness, swelling and pain and less often serious reactions. Safety concerns led to the acellular DTaP vaccines, which replaced it in the 1990s; a five-dose DTaP series has been recommended since 1997. Tdap for adolescents and adults followed in 2005, and Tdap in every pregnancy in 2012. Single-antigen tetanus vaccine (TT) stopped being made in 2013. No "pertussis-only" vaccine is licensed in the United States.

The recommendations

• Children, 2 months to 6 years: five DTaP doses, at 2, 4 and 6 months, 15–18 months, and 4–6 years. The first can be given as early as 6 weeks; the fourth at least 6 months after the third and not before 12 months; a fifth is not needed if the fourth is given at age 4 or older.
• Ages 11–18: one dose of Tdap, preferably at 11–12.
• Adults 19 and older who have never had Tdap: one dose in place of a Td booster, without delay, whenever the last tetanus shot was.
• Every adolescent and adult after Tdap: a Td booster every 10 years for life.
• Pregnant women: Tdap in every pregnancy, between 27 and 36 weeks — earlier in that window gives the baby the most antibodies — whatever her history. It can be given with flu vaccine. A woman who has never had Tdap and did not get it during pregnancy should get it right after birth.
• Close contacts of infants (parents, siblings, grandparents, child care and health care providers) who have never had Tdap: one dose, ideally at least 2 weeks before contact.
• Health care personnel: one dose of Tdap as soon as feasible if never received, then routine Td.

Tdap is not recommended more than once for the general population, except in pregnancy. Some uses — in pregnancy, in children 7–10, and in adults 65 and older for one product — are off-label; ACIP judged that the benefits outweigh the risks.

Catching up and special situations

• Children under 7 behind schedule need not restart the series, but should not exceed six diphtheria-tetanus doses before age 7.
• Ages 7–18 not fully vaccinated: Tdap as one dose (preferably the first) of catch-up, then Td; those given Tdap at 7–10 get another at 11–12.
• Unvaccinated adults: three doses — Tdap, then Td 4 weeks later, then Td 6–12 months after that.
• Wounds: people who completed three tetanus doses and had one within the past 5 years need nothing more. Others may need a tetanus vaccine and tetanus immune globulin, given in separate sites; people with HIV or severe immunodeficiency with contaminated wounds get the immune globulin regardless.
• After pertussis, tetanus or diphtheria: vaccinate anyway — infection does not give lasting immunity.
• Seizures: delay pertussis vaccine until a child's neurologic condition is assessed and stable; a family history of seizures is not a reason to withhold it.

The three diseases

Protection from the acellular pertussis vaccines fades: cases rose from the mid-2000s among children aged 7–10, among the first to receive only DTaP, and later among 13- and 14-year-olds. Siblings have become the most common source of infection for infants. By age 70, only 45 percent of men and 21 percent of women in a national survey had protective tetanus antibodies.

Reported U.S. pertussis cases, 1922–2016. Credit: CDC, Morbidity and Mortality Weekly Report.

U.S. tetanus incidence and deaths, 1947–2016. Credit: CDC, Morbidity and Mortality Weekly Report.

Coverage and what's next

In 2015, 95.0 percent of children aged 19–35 months had at least three DTaP doses but only 84.6 percent had four, short of the 90 percent target; 86.4 percent of adolescents had Tdap, up from 10.8 percent in 2006. Only 23.1 percent of adults had Tdap, and 48.8 percent of pregnant women got it in 2015–16. DTaP and Tdap remain the best tools against pertussis and are safer than DTP, but they do not give long-term protection and may not stop transmission. Protecting infants, who are at greatest risk of dying, is the immediate priority.

Sources

Based on "Prevention of Pertussis, Tetanus, and Diphtheria with Vaccines in the United States: Recommendations of the Advisory Committee on Immunization Practices (ACIP)," by Jennifer L. Liang and colleagues, MMWR Recommendations and Reports, Centers for Disease Control and Prevention; a work of the United States government in the public domain.