Surveys on new human malaria in South East Asia

1.在1997-1998年期间，利用吖啶橙子染色法在泰国、印度尼西亚、缅甸、老挝、越南和中国进行了疟疾的实地调查。在这些国家共对约13000名志愿者进行了检查，并在约2000年发现了疟疾患者。对部分阳性标本进一步进行了PCR诊断，并在中国和东南亚地区发现了一种新的三日疟原虫变异株。该变异体在核糖体RNA基因中具有突变序列，在靶区域缺失19-bp。新变异体的靶序列前半部分与间日疟原虫和诺氏疟原虫的靶序列相同，后半部分与疟疾疟原虫的靶序列一致。由于这种变异型在非洲没有发现，因此很可能这种变异型只分布于东亚。所有感染该变异型的患者均与其他疟疾种混合感染。为了进一步的分子和临床研究，找到单独感染这种变异形式的患者是必要的。还进行了G6 PD缺乏症快速检测的现场试验，并进行了疟疾的现场快速诊断。通过使用这两种快速测试，伯氨喹是安全的处方疟疾患者感染间日疟原虫和恶性疟原虫配子体。

1. During 1997-1998, field surveys of malaria were conducted in Thailand, Indonesia, Myanmar, Laos, Vietnam and China by using an acridine orange staining. A total of about 13000 volunteers were examined in these countries, and malaria patients were detected in about 2000.2. PCR-based diagnoses were further examined in a part of malaria-positive samples, and a new variant form of P.malariae was detected from China and Southeast Asia. This variant form possessed mutated sequence in the ribosomal RNA gene with 19-bp deletion at the target region.3. The anterior part in the target sequence of the new variant form was the same with those of P.vivax and P.knowlesi, while its posterior part was corresponding to that of P.malariae. As this variant form was not found in Africa, it is probable that the variant form may distribute only in East Asia. All of patients infected with this variant form were mix-infected with other malaria species. For further studies on molecularly and clinically, it is essential to find patients infected singly with this variant form.4. Field trials of a rapid test for G6PD deficiency were also performed with a rapid diagnosis of malaria on-site. By using these two rapid tests, primaquine was prescribed safely to malaria patients infected with P.vivax and gametocytes of P.falciparum.