尽管在美国95%以上的学龄儿童接种过麻疹疫苗,但在学校中麻疹大爆发不断出现,并且大多数病例见于以前免疫过的儿童。作者利用1986年在美国威斯康星州戴恩县麻疹大爆发的数据,进行了病例-对照研究以评价疫苗接种失败的危险因素,并对在学校进行复种的费用-效益关系作了分析。219例麻疹病人中有185(84%)例是分布于30个学校的学生。作者分别选择了170例和144名爆发前接种过单剂疫苗的病人和 Although more than 95% of school-age children in the United States have been vaccinated against measles, measles outbreaks continue to occur in schools, and most of the cases occur in previously immunized children. Using data from the measles outbreak in Dane County, Wisconsin, USA, in 1986, the authors conducted case-control studies to assess the risk factors for failed vaccination and to analyze the cost-benefit relationship for multiple cropping in schools. Of 219 patients with measles, 185 (84%) were students distributed in 30 schools. The authors selected 170 patients and 144 patients who had received a single dose of vaccine prior to the outbreak