贵州省疟疾实验室诊断能力与疫情风险分析

Laboratory diagnosis capabilities and epidemic risk analysis for malaria in Guizhou province

目的评价贵州省疟疾报告病例的实验室诊断情况、基层实验室诊断能力与疟疾疫情风险。方法以贵州省近3年的疟疾疫情数据及省疾病预防控制中心疟疾实验室复核的血片和PCR检测结果进行实验室间比对分析。结果贵州省疟疾疫情从2008年开始逐年下降,年报告发病率从2008年的3.43/10万降至2010年的1.04/10万。2009～2011年全省92.26%的网报病例进行了镜检,省级实验室对县级镜检的血片进行抽检,阴性片符合率达100%(303/303),阳性片符合率达89.57%(103/115),镜检总体符合率为97.13%(406/418)。县级实验室镜检阳性病例的滤纸血,采用PCR方法检测,阳性率为96.00%(24/25),镜检阴性的病例或临床诊断为疟疾、疑似疟疾和不明原因的发热病人滤纸血,经PCR检测,阴性率为98.92%(92/93),县级实验室镜检结果与PCR法检测结果的总体符合率为98.31%(116/118)。结论经省级实验室镜检复核和PCR方法比对,县级实验室镜检结果的可靠性较高,特别是阴性结果更为可靠,阳性结果有10%的误诊,因此全省各级疾病预防控制及医疗机构,应当依据实验室检测结果对网报病例进行订正。

Objective To evaluate diagnosis in the laboratory for the reported cases of malaria in Guizhou as well as laboratory diagnosis capability in basic level and malaria epidemic risk.Methods Compare data of malaria collected in recent three years as well as the blood films rechecked by Malaria laboratory of provincial CDC with PCR detection.Results Malaria epidemic situation in Guizhou province reduced year by year,the reported incidence of malaria in 2008 was 3.43/100 000 and reduced to1.04/100 000 in 2010.In recent three years,92.26% of net reported cases were detected by microscopic examination and provincial laboratory checked the blood films samples from county-level.The results showed： Negative blood films coincidence rate was 100%（303/303）,positive blood films coincidence rate was 89.57%（103/115）,and overall coincidence rate for microscopic examination was 97.13%（406/418）.County laboratory detected the positive cases＇ filter papers with PCR and the positive rate was 96.00%（24/25）,using the same method to detect the filter papers of negative cases or malaria cases,suspected malaria cases and patients with fever of undetermined origin,the negative rate was 98.92%（92/93） and overall coincidence rate was 98.31%（116/118） for microscopic examination and PCR testing results of county laboratories.Conclusion Through the comparison between microscopic examination and PCR test in provincial laboratory,we found a higher reliability of the microscopic examination results at the county laboratory,especially negative results are more reliable,but there are nearly 10% of misdiagnosis in positive results.So the institutions for disease control and prevention and other medical institutions at all levels of our province should make a revisal on the net reported cases based on the laboratory testing results.