三种疟原虫检测方法的比较研究

应用聚合酶链反应（PCR）及微滴度板杂交试验（MPH）对来自高疟疾流行区、收集于滤纸片的112例干血滴样品进行检测,并对同一人群作镜检进行比较。结果表明显微镜检查恶性疟原虫检出率27.69%（31／112）,而CR及MPH方法检出率分别为37.5%（42／112）、50％（56／112）。实验结果提示镜检虽然简便、易行、成本低,但由于一般观察极限的限制,影响了检出率。PCR方法敏感、特异,疟原虫检出率较高,但有假阳性及假阴性,且无法作种属鉴定。三种方法中MPH方法恶性疟原虫检出率最高,不仅可进行种属鉴定,也可进行混合感染的检测。此法疟原虫检出率71.43%（80／112）,其中混合感染者为39.29%（44／112）。但该法的结果难以被其它方法证实。表明该法特异性尚待证实,加上MPH成本高,这也限制了该法在临床实践及大范围普查的应用。

COMPARISONS OF THREE METHODS FOR THE DETECTION OF MALARIA PARASITES IN SOLOMON ISLANDS

We examined 112 samples collected on the filter paper disks in the Solomon islands to compare the value of polymerase chain reaction (PCR)and microtiter plate hybridization (MPH)methods with conventional microscopic examination for detection of malaria.The results showed that with optical examination the positive rate of Plasmodium falciparum was 27.69%(31/112).They increased respectively to 37.5%(42/112)and 50%(56/112)when detected by PCR and MPH methods.These results suggested that although optical examination is low in cost and convenient,but it is restricted by its detection limit,which influences its results.The PCR method is a sensitive and specific method,but there also were false positives and negatives sometimes when detected by this method and it is difficult to identify the species of malaria with this method.Among these methods the highest positive rate of malaria is by MPH method.With MPH method,we could not only identify the species of malaria,but also could detect the mixed infection of malaria.However,in our study,the positives of malaria were even up to 71.43%(80/112)and the mixed infection was 39.29%(44/112),which were difficult to reprove by other two methods.This result might suggest that the specificity of MPH method still requires further study and other drawback is its high cost,which also limits its wide application in clinic practice.