1986年3月上旬,我们在彭泽县城开展流脑 A 群抗体水平与带菌状况关系的调查。县一中学生于一年前接种流脑 A 群多糖体菌苗为接种组,县二中学生为未接种组。当时县城未发生流脑病人,两组除免疫史不同外,诸如年龄、性别、环境、医疗保健、生活条件、感染机会等因素相似。两组每位学生均采0.2毫升血,用 ELISA 法测定 In early March 1986, we conducted a survey of the relationship between the level of antibody against Group A meningitis and the carriage status in Pengze County. County middle school students inoculated with a group of meningitis A group of polysaccharide vaccine for the inoculation group a year ago, the county two non-inoculated group of secondary school students. At that time, there was no meningococcal disease in the county seat. In addition to the different immunization history, the two groups had similar factors such as age, gender, environment, health care, living conditions and infection chances. Two students each collected 0.2 ml of blood, measured by ELISA