调查一所小学风疹暴发流行，发病率36．93％。测定82名观察对象的双份血清，感染前抗体几何平均滴度13．86，感染后升至494．98。总感染率73．17％，显性感染率37．81％，隐性感染率35.37％。血凝抑制（HI）抗体滴度≤1：32的暴露者都有发生风疹的可能，绝大多数患者感染时的抗体滴度≤1：16，≥1：64的暴露者绝大多数可以抵抗风疹的再感染。 Investigation of a primary school rubella outbreak, the incidence rate of 36.93%. Two sera from 82 subjects were tested. The geometric mean antibody titer before infection was 13.86 and rose to 494.98 after infection. The total infection rate was 73.17%, the dominant infection rate was 37.81% and the recessive infection rate was 35.37%. Rubella (HI) antibody titers <1: 32 exposure are likely to occur rubella, the vast majority of patients infected with antibody titers ≤ 1: 16, ≥ 1: 64 most of the exposed people can resist Rubella reinfection.