2012年元谋县麻疹传播因素调查分析

Investigation of risk factors of measles in Yuanmou County in the year 2012

目的分析2012年元谋县麻疹病例发生的原因，以便采取更为有效、科学的麻疹防控措施，为最终实现消除麻疹的目标提供科学参考依据。方法用统一设计的表格对病例进行个案调查，对病例村开展麻疹传播危险因素调查；用随机抽样方法抽取30个村委会开展麻疹接种率调查；制定麻疹IgG抗体滴度检测方案，随机抽取两个村委会不同年龄段的人群和到县人民医院就诊的不同年龄段的人群共406人开展麻疹抗体滴度检测。结果2012年元谋县发生4例麻疹散发病例，4例病例中无免疫史2例，基础免疫史不详1例，有免疫史1例；发病年龄8月龄～17月龄3例，8岁1例；对4例病例村开展麻疹传播危险因素调查结果表明，疫点周围无麻疹传播危险因素；对30个村委会的8月龄至4岁共240名儿童开展麻疹接种率调查，含麻疹成份疫苗的接种率达100％，对不同年龄段的人群共406人开展麻疹抗体滴度检测，麻疹抗体滴度〈200MIU／mL2人，≥200MIU／mL137人，≥800MIU／mL267人，抗体阳性率达99．51％，抗体保护率达65．76％，抗体保护率最高为18月～5岁组，达89．09％，最低20～34岁组，为40．00％，各年龄组间抗体保护率有显著性差异（χ^2=50．81，P〈0．005）。结论元谋县适龄儿童麻疹疫苗接种率较高，基础免疫工作扎实，麻疹抗体阳性率较高。2012年发生的麻疹病例均为散发，发生麻疹流行和暴发的可能性不大。麻疹发病的主要原因是个别儿童存在免疫空白，今后要加强对个别免疫空白人群的麻疹疫苗接种工作，提高及时接种率，消除免疫空白人群。

Objective To explore the causes of measles in Yuanmou County in the year 2012, to provide evidence for the effective treatment, control and prevention of measles. Methods Individual cases were interviewed with a uniform questionnaire. The risk factors were investigate in the villages where measles occurred. Measles inoculation rate was surveyed in 30 villages with random sampling method. Measles antibody titer detection method was formulated. 406 villagers of different ages in two villages were randomly chosen and their measles antibody was detected in the county hospital. Results There were four sporadic measles cases in Yuanmou County in 2012. Of them, one had measles inoculation, two had no measles inoculation, and one＇s inoculation history was unclear. Three cases developed measles during 8 to 17 months, one at 8 years. The investigation of risk factors showed that there were no risk factors around the epidemic spot. The 240 children aged 8 months to 4 years in the 30 villages surveyed showed that all children were vaccinated. Among the 406 villagers, the antibody titer 〈200 MIU/ mL in 2,≥200 MIU/mL in 137, ≥800 MIU/mL in 267 villagers. The positive rate of antibody was 99.51%, and antibody protection rate was 65.76 %. People aged 18 months to 5 years had the highest antibody protection rate of 89.09%, while people aged 20 to 34 years had the lowest antibody protection rate of 40.00%, with statistical difference （X^2= 50. 81, P 〈 0. 005）. Conclusions Yuanmou County. The positive antibody protection The measles inoculation rate was high among children in rate was high. The measles cases occurred in 2012 were sporadic. There was low possibility of measles prevalence and epidemic. The major cause of measles was that some children were not vaccinated. Therefore, vaccination was essential for the control and prevention of measles.