Sustained transmission of whooping cough in vaccinated children of 1-5 years of age in a nursery school, in Florida, USA

Abstract
In September 2013, health officials from Tallahassee County, Florida, in the United States, were informed of a laboratory-confirmed pertussis case in a 1-year preschool participant. Over a 5-month period, 26 (22%) students of 1-5 years, 2 members of the same kindergarten and 11 family members met the definition of national pertussis case. Four people during this outbreak were hospitalized for the clinical management of pertussis symptoms. Only 5 students, including 2 students with whooping cough, had not received the full set of pertussis vaccinations. Attack rates in 1 class for all students who received the full set of pertussis vaccinations approached 50%. This outbreak raises concerns about the effectiveness of the vaccine in this preschool age group and reinforces the idea that recent pertussis vaccination should not deter doctors from diagnosing, testing or treating people with pertussis-compatible disease.