Bureau of Vector-Borne Diseases, Ministry of Public Health, Nonthaburi, Thailand.
Malar J. 2012 Aug 21;11:288. doi: 10.1186/1475-2875-11-288.
Asymptomatic carriage of Plasmodium falciparum and Plasmodium vivax is common in both low-and high-transmission settings and represents an important reservoir of infection that needs to be targeted if malaria elimination is to succeed.
Mass blood examinations (475 individuals) were conducted in two villages in Mae Hong Son, an area of endemic but low-transmission malaria in the north-west of Thailand. The microscopist at the local malaria clinic did not detect any infections. Pools of four samples were screened by real-time PCR; individual members of all of the positive pools were then re-examined by expert microscopy and by a second species-specific PCR reaction.
Eight subjects were found to be positive by both PCR and expert microscopy and one was found to be positive by PCR alone. The slides contained asexual stage parasites of P. vivax, P. falciparum and Plasmodium malariae, but no gametocytes. The local clinic was notified within two to eight days of the survey.
A combination of pooling, real-time PCR and expert microscopy provides a feasible approach to identifying and treating asymptomatic malaria infections in a timely manner.
在低传播和高传播环境中，无症状携带恶性疟原虫和间日疟原虫都很常见，这是感染的一个重要来源，如果要成功消除疟疾，就需要对其进行针对性治疗。
在泰国西北部疟疾流行但低传播的湄宏顺府的两个村庄进行了大规模血液检查（475 人）。当地疟疾诊所的显微镜检查人员未发现任何感染。对四个样本的四个样本池进行实时 PCR 筛查；对所有阳性池的个体成员进行专家显微镜检查和第二次种特异性 PCR 反应。
有 8 人通过 PCR 和专家显微镜检查均呈阳性，1 人仅通过 PCR 检查呈阳性。载玻片上含有间日疟原虫、恶性疟原虫和疟原虫的无性生殖阶段寄生虫，但没有配子体。在调查后的两到八天内通知了当地诊所。
混合、实时 PCR 和专家显微镜检查的组合为及时发现和治疗无症状疟疾感染提供了一种可行的方法。
