Estimating vaccine efficacy from small outbreaks
利用小规模暴发估计疫苗效力
Let CV and C0 denote the number of cases among vaccinated and unvaccinated individuals, respectively, and let υ be the proportion of individuals vaccinated. The quantity ê = 1–(1–υ)CV/(υC0) = 1–(relative attack rate) is the most used estimator of the effectiveness of a vaccine to protect against infection. For a wide class of vaccine responses, a family of transmission models and three types of community settings, this paper investigates what ê actually estimates. It does so…