(HealthDay News) – During a pertussis outbreak, adolescents who were given whole-cell pertussis vaccines in childhood are more protected than those given acellular pertussis vaccines, according to research published online May 20 in Pediatrics.
Nicola P. Klein, MD, PhD, from the Northern California Kaiser Permanente Vaccine Study Center in Oakland, and colleagues analyzed data from individuals (born 1994–1999) who received four pertussis-containing vaccines during the first two years of life. Comparisons were made between pertussis polymerase chain reaction (PCR)-positive cases (138) with PCR-negative cases (899) as well as matched controls (54,339). The vaccine types considered were diphtheria-tetanus-whole cell pertussis (DTwP), diphtheria-tetanus-acellular pertussis (DTaP), or mixed DTwP/DTaP.
The researchers found that teenagers who had received four DTwPs were much less likely to be pertussis PCR-positive than those who had received four DTaPs (odds ratio, 5.63) or mixed DTwP/DTaP vaccines (odds ratio, 3.77). There was a significant increase in pertussis risk with a decreasing number of DTwP doses.
“Teenagers who received DTwP vaccines in childhood were more protected during a pertussis outbreak than were those who received DTaP vaccines,” Klein and colleagues conclude.
Two authors disclosed financial ties to pharmaceutical companies, including GlaxoSmithKline, Sanofi-Pasteur, Pfizer, and Merck, all of which manufacture the pertussis vaccines used in the study.