RT Journal
A1 Skoff TH, Cohn AC, Clark TA, Messonnier NE, Martin SW
T1 EArly impact of the us tdap vaccination program on pertussis trends
JF Archives of Pediatrics & Adolescent Medicine
JO Archives of Pediatrics & Adolescent Medicine
YR 2012
FD April 1
VO 166
IS 4
SP 344
OP 349
DO 10.1001/archpediatrics.2011.1093
UL http://dx.doi.org/10.1001/archpediatrics.2011.1093
AB Objective 
                  To evaluate the impact of the adolescent Tdap (tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine) vaccination program on pertussis trends in the United States.Design 
                  Retrospective analysis of nationally reported pertussis cases, January 1, 1990, through December 31, 2009.Setting 
                  United States.Participants 
                  Confirmed and probable pertussis cases.Intervention 
                  The US Tdap vaccination program.Main Outcome Measure 
                  Rate ratios of reported pertussis incidence (defined as incidence among 11- to 18-year-olds divided by the combined incidence in all other age groups) modeled through segmented regression analysis and age-specific trends in reported pertussis incidence over time.Results 
                  A total of 200 401 pertussis cases were reported in the United States from 1990 to 2009. Overall incidence ranged from 1.0 to 8.8 per 100 000 persons (1991 and 2004, respectively). Slope coefficients (estimated annual rate of change in rate ratios) from segmented regression showed a steady increase in pertussis incidence among adolescents 11 to 18 years old compared with all other age groups before Tdap introduction (slope = 0.22; P < .001), and a steep decreasing trend post introduction (slope = −0.48; P < .001), suggesting a direct impact of vaccination among adolescents. Indirect effects of adolescent vaccination were not observed among infants younger than 1 year.Conclusions 
                  Changes in pertussis incidence in the United States from 2005 to 2009 revealed a divergence between 11- to 18-year-olds and other age groups, suggesting that targeted use of Tdap among adolescents reduced disease preferentially in this age group. Increased Tdap coverage in adolescents and adults is needed to realize the full direct and indirect benefits of vaccination.