为了解东营市健康人群的流行性乙型脑炎 (乙脑 )免疫水平 ,于 1999年对不同年龄组人群进行了乙脑免疫水平的监测 ,现将结果报告如下。1　监测对象与检测方法　在东营市 3个县 (区 ,下同 ) ,每县按随机抽样方法抽取 3个点 ,对健康人群按 2岁、2～ 4岁、5～ 7岁、8～ 10岁、11～ In order to understand the epidemic of Japanese encephalitis (JE) in healthy population of Dongying City, the level of JE immunization was monitored in different age groups in 1999, and the results are reported as follows. A monitoring object and detection method In Dongying City, 3 counties (districts, the same below), each county by random sampling method to extract three points, healthy people by 2 years old, 2 to 4 years old, 5 to 7 years old, 8 to 10 Years old, 11 ~