We report the first documented mixed outbreak of B. pertussis and B. holmesii infections. Bordetella holmesii particularly affected adolescents. Although laboratory capacity limitations might inhibit routine use of multitarget PCR for clinical diagnosis, focused testing and enhanced surveillance might improve understanding the burden of B. holmesii infection.

WHAT'S KNOWN ON THIS SUBJECT: Infants aged ,2 months are at highest risk for pertussis morbidity and mortality but are too young to receive pertussis vaccines. To protect young infants, the Advisory Committee on Immunization Practices recommends mothers receive 1 dose of Tdap during pregnancy. WHAT THIS STUDY ADDS:This article evaluates the effect of Tdap during pregnancy compared with postpartum Tdap and cocooning in preventing infant pertussis cases, hospitalizations, and deaths, as well as their relative cost-effectiveness. abstract BACKGROUND: Infants ,2 months of age are at highest risk of pertussis morbidity and mortality. Until recently, the US Advisory Committee on Immunization Practices (ACIP) recommended protecting young infants by "cocooning" or vaccination of postpartum mothers and other close contacts with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis, adsorbed (Tdap) booster vaccine. ACIP recommends pregnancy vaccination as a preferred and safe alternative to postpartum vaccination. The ACIP cocooning recommendation has not changed. METHODS:We used a cohort model reflecting US 2009 births and the diphtheria-tetanus-acellular pertussis schedule to simulate a decision and cost-effectiveness analysis of Tdap vaccination during pregnancy compared with postpartum vaccination with or without vaccination of other close contacts (ie, cocooning). We analyzed infant pertussis cases, hospitalizations, and deaths, as well as direct disease, indirect, and public health costs for infants in the first year of life. All costs were updated to 2011 US dollars.RESULTS: Pregnancy vaccination could reduce annual infant pertussis incidence by more than postpartum vaccination, reducing cases by 33% versus 20%, hospitalizations by 38% versus 19%, and deaths by 49% versus 16%. Additional cocooning doses in a father and 1 grandparent could avert an additional 16% of cases but at higher cost. The cost per qualityadjusted life-year saved for pregnancy vaccination was substantially less than postpartum vaccination ($414 523 vs $1 172 825).CONCLUSIONS: Tdap vaccination during pregnancy could avert more infant cases and deaths at lower cost than postpartum vaccination, even when postpartum vaccination is combined with additional cocooning doses. Pregnancy dose vaccination is the preferred alternative to postpartum vaccination for preventing infant pertussis. Pediatrics 2013;131: e1748-e1756 AUTHORS: