(HealthDay News) – Universal administration of the tetanus-diphtheria-acellular pertussis (Tdap) vaccine to adolescents correlates with a decrease in pertussis hospitalizations among vulnerable infants, according to a study published online Oct. 21 in Pediatrics.
To examine whether patterns of pertussis hospitalization for infants changed with adoption of Tdap vaccination among adolescents, Katherine A. Auger, MD, from the University of Cincinnati, and colleagues used data from the Nationwide Inpatient Sample to identify infants (aged <1 year) diagnosed with pertussis. Expected hospitalization patterns if Tdap had not been available, calculated from preimplementation years (2000–2005), were compared with the observed rates for 2008–2011. Data from the early implementation period (2006–2007) were excluded from the analysis.
The researchers found that in 2000, the incidence of hospitalization for pertussis was 5.82 discharges per 10,000 infants in the U.S. population. During pre-Tdap years the rate increased by a mean of 0.64 pertussis discharges per 10,000 infants per year (P for trend=0.004). In 2008, 2009, and 2011, the observed hospitalization rates for pertussis were significantly lower than expected among infants. In 2010 there were no significant differences between the observed and expected rates of hospitalization.
“The implementation of policy for universal vaccination among adolescents against pertussis appears to have been partially effective in decreasing the rates of hospitalization for pertussis among infants,” the authors write.