Pertussis Vaccine: Just One Dose Prevents Death

Deborah Lehman, MD reviewing Tiwari TSP et al. Pediatrics 2015 May 4.

Unimmunized infants are at the highest risk for death.

Despite widespread use of the pertussis vaccine, pertussis continues to circulate, causing cough illness in older children and adults and severe disease and sometimes death in young infants. Reasons for its persistence and recent outbreaks (>28,000 cases reported in 2014) include waning immunity and improved diagnostic techniques.

Investigators from the CDC reviewed all confirmed and probable pertussis cases in the U.S. from 1991 to 2008 in infants aged <365 days and assessed the role of vaccination in preventing pertussis-related deaths.

Of 45,404 pertussis cases recorded, 258 deaths occurred (0.57%). The highest death rates were in Hispanic infants and in those of American Indian/Alaska Native race. All fatal cases were in infants aged <34 weeks, and among infants aged ≥42 days, the receipt of at least one vaccine dose was associated with a 72% decrease in relative risk for pertussis-associated death. A multivariable analysis of infants aged ≥42 days showed that by immunizing infants at age 6 weeks (the youngest age recommended by the CDC) rather than at age 2 months, 68 deaths would have been prevented.

Citation(s):

Tiwari TSP et al. First pertussis vaccine dose and prevention of infant mortality. Pediatrics 2015 May 4.