(HealthDay) -- Pertussis rates may reach record levels this year in the United States, where Washington state is experiencing an ongoing epidemic, according to a report published in the July 20 issue of the U.S. Centers for Disease Control and Prevention's Morbidity & Mortality Weekly Report.
Chas DeBolt, M.P.H., of the CDC in Atlanta, and colleagues reviewed all pertussis cases reported between Jan. 1 and June 16 of this year to assess clinical, epidemiologic, and laboratory factors associated with the rise in pertussis cases in the state of Washington. This rise prompted the state's Secretary of Health to declare an epidemic in April.
The researchers found that 2,520 pertussis cases were reported in the first six months of 2012, a 1,300 percent increase over the first six months of 2011. Disease rates were high in infants and children under the age of 10, but also in 13- to 14-year-old adolescents who had received the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine, which suggests immunity might wane soon after Tdap vaccination.
"The focus of prevention and control efforts is the protection of infants and others at greatest risk for severe disease and improving vaccination coverage in adolescents and adults, especially those who are pregnant," DeBolt and colleagues conclude. "Pertussis vaccination remains the single most effective strategy for prevention of infection."
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