Protection against pertussis waned during the 5 years after the fifth dose of DTaP. (Funded by Kaiser Permanente).

BACKGROUND: During the 1990s, the United States switched from combined diphtheria, tetanus toxoids, whole-cell pertussis (DTwP) vaccines to combined acellular pertussis (DTaP) vaccines because of safety concerns. After a 2010–2011 pertussis outbreak, we sought to evaluate whether disease risk in 10 to 17 year olds differed between those who previously received DTwP from those who received DTaP. METHODS: A case-control study among individuals born from 1994 to 1999 who received 4 pertussis-containing vaccines during the first 2 years of life at Kaiser Permanente Northern California (KPNC). We separately compared pertussis polymerase chain reaction (PCR)-positive cases with PCR-negative and KPNC-matched controls. We assessed risk of pertussis relative to vaccine type in early childhood (4 DTwPs, mixed DTwP/DTaP, or 4 DTaPs) by using conditional logistic regression stratified for calendar time and adjusted for gender, race, medical clinic, and receipt of reduced antigen content acellular pertussis (Tdap) vaccine. RESULTS: We compared 138 PCR-positive cases with 899 PCR-negative and 54 339 KPNC-matched controls. Teenagers who had received 4 DTwPs were much less likely to be pertussis PCR-positive than those who had received 4 DTaPs (odds ratio 5.63, 95% confidence interval 2.55–12.46) or mixed DTwP/DTaP vaccines (odds ratio 3.77, 95% confidence interval 1.57–9.07). Decreasing number of DTwP doses was significantly associated with increased pertussis risk (P < .0001). CONCLUSIONS: Teenagers who received DTwP vaccines in childhood were more protected during a pertussis outbreak than were those who received DTaP vaccines.

BACKGROUND: Vaccination against pertussis during pregnancy is recommended to protect newborns, yet there is limited information about the effectiveness of maternal tetanus toxoid, reduced diphtheria toxoid, acellular pertussis (Tdap) vaccine before the first infant dose of diphtheria, tetanus and acellular pertussis (DTaP) vaccine and during the first year of life in infants who have received DTaP.

BACKGROUND AND OBJECTIVE: Because the effectiveness of diphtheria-tetanus-acellular pertussis (DTaP) vaccine wanes substantially after the fifth dose at ages 4 to 6 years, there is a growing cohort of adolescents who rely on tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) for protection against pertussis. Yet despite high Tdap vaccine coverage among adolescents, California experienced large pertussis outbreaks in 2010 and 2014. We investigated Tdap vaccine effectiveness (VE) and waning within Kaiser Permanente Northern California among adolescents exclusively vaccinated with DTaP vaccines.

Objective To assess the effectiveness of reduced acellular pertussis (Tdap) vaccines in adolescents and adults.

A live attenuated zoster vaccine was licensed in the United States in 2006 for prevention of shingles in persons aged 60 years or older; the indication was extended in 2011 to cover those aged 50–59 years. We assessed vaccine effectiveness (VE) against shingles for 8 years after immunization at Kaiser Permanente Northern California. VE was estimated by Cox regression with a calendar timeline that was stratified by birth year. We adjusted for demographics and time-varying covariates, including comorbidities and immune compromise. From 2007 to 2014, 1.4 million people entered the study when they became age eligible for vaccination; 392,677 (29%) received the zoster vaccine. During 5.8 million person-years of follow-up, 48,889 cases of shingles were observed, including 5,766 among vaccinees. VE was 49.1% (95% confidence interval (CI): 47.5, 50.6) across all follow-up. VE was 67.5% (95% CI: 65.4, 69.5) during the first year after vaccination, waned to 47.2% (95% CI: 44.1, 50.1) during the second year after vaccination, and then waned more gradually through year 8, when VE was 31.8% (95% CI: 15.1, 45.2). Unexpectedly, VE in persons vaccinated when they were aged 80 years or older was similar to VE in younger vaccinees, and VE in persons vaccinated when immune compromised was similar to VE in persons vaccinated when immune competent.

(Abstracted from Pediatrics 2017;139(5):e20164091) Pertussis is a virulent and life-threatening respiratory infection, particularly in infants, caused by the bacteria Bordetella pertussis. Tetanus toxoid, reduced diphtheria toxoid, acellular pertussis (TDaP) vaccination during pregnancy is recommended to protect newborns against pertussis.

Results of this postlicensure evaluation of LAIV safety in US children aged 5-17 years are consistent with preapproval clinical studies and Vaccine Adverse Event Reporting System reports, both of which demonstrated no significant increase in asthma/wheezing events or other adverse outcomes among eligible children who received LAIV.