TABLE 1.

Chickenpox Attack Rate by Years Since Vaccination: Oregon Elementary School Outbreak

Years Since VaccinationCasesTotal StudentsAttack Rate, %
≤21283.6
>2–30120
>3–41156.7
>4–51323.1
>5–693923.1
>662623.1
Total1813412
  • The table includes only vaccinated students without a prior history of chickenpox in classrooms attended by case students.