BACKGROUND AND OBJECTIVES: Pertussis incidence is increasing, possibly due to the
introduction of acellular vaccines, which may have decreased the durability of immune …

OBJECTIVE: To assess the risk of pertussis by time since vaccination in children in
Minnesota and Oregon who received 5 doses of acellular pertussis vaccines (DTaP) …

OBJECTIVE: Data on the effectiveness of the diphtheria–tetanus–acellular pertussis (DTaP)
vaccine in the first 4 years of life are sparse. We evaluated the vaccine effectiveness (VE) of …

Background In the United States, children receive five doses of diphtheria, tetanus, and
acellular pertussis (DTaP) vaccine before 7 years of age. The duration of protection after five …

OBJECTIVES: To determine pertussis risk by diphtheria-tetanus-acellular pertussis (DTaP)
vaccination status and time since last DTaP dose. METHODS: Children born at Kaiser …

METHODS: We modeled pertussis risk in relation to Tdap vaccination status among
adolescents beginning on their 10th birthday. We estimated the hazard ratio (HR) for each …

Background. We estimated the vaccine effectiveness (VE) of tetanus-diphtheria-acellular
pertussis vaccine (Tdap) for preventing pertussis among adolescents during a statewide …

BACKGROUND: Acellular pertussis vaccines replaced whole-cell vaccines for the 5-dose
childhood vaccination series in 1997. A sixth dose of pertussis-containing vaccine, tetanus …

A large, randomized, placebo-controlled clinical trial in Italy on two three-component
pertussis vaccines, given as DTaP in infancy, one manufactured by SmithKline and …

BACKGROUND: During the 1990s, the United States switched from combined diphtheria,
tetanus toxoids, whole-cell pertussis (DTwP) vaccines to combined acellular pertussis …