Instituto de Medicina Tropical Alexander von Humboldt Universidad Peruana Cayetano Heredia, Lima, Peru.
PLoS One. 2010 Jan 25;5(1):e8091. doi: 10.1371/journal.pone.0008091.
Malaria rapid diagnostic tests (RDTs) offer significant potential to improve the diagnosis of malaria, and are playing an increasing role in malaria case management, control and elimination. Peru, along with other South American countries, is moving to introduce malaria RDTs as components of malaria control programmes supported by the Global Fund for AIDS, TB and malaria. The selection of the most suitable malaria RDTs is critical to the success of the programmes.
Eight of nine microscopy positive P. falciparum samples collected in Iquitos, Peru tested negative or weak positive using HRP2-detecting RDTs. These samples were tested for the presence of pfhrp2 and pfhrp3 and their flanking genes by PCR, as well as the presence of HRP proteins by ELISA. To investigate for geographic extent of HRP-deleted parasites and their temporal occurrence a retrospective study was undertaken on 148 microscopy positive P. falciparum samples collected in different areas of the Amazon region of Peru.
Eight of the nine isolates lacked the pfhrp2 and/or pfhrp3 genes and one or both flanking genes, and the absence of HRP was confirmed by ELISA. The retrospective study showed that 61 (41%) and 103 (70%) of the 148 samples lacked the pfhrp2 or pfhrp3 genes respectively, with 32 (21.6%) samples lacking both hrp genes.
This is the first documentation of P. falciparum field isolates lacking pfhrp2 and/or pfhrp3. The high frequency and wide distribution of different parasites lacking pfhrp2 and/or pfhrp3 in widely dispersed areas in the Peruvian Amazon implies that malaria RDTs targeting HRP2 will fail to detect a high proportion of P. falciparum in malaria-endemic areas of Peru and should not be used. RDTs detecting parasite LDH or aldolase and quality microscopy should be use for malaria diagnosis in this region. There is an urgent need for investigation of the abundance and geographic distribution of these parasites in Peru and neighbouring countries.
疟疾快速诊断检测（RDT）为改善疟疾诊断提供了巨大的潜力，在疟疾病例管理、控制和消除方面发挥着越来越重要的作用。秘鲁与其他南美国家一样，正在引入疟疾 RDT，作为全球抗击艾滋病、结核病和疟疾基金支持的疟疾控制规划的组成部分。选择最合适的疟疾 RDT 对项目的成功至关重要。
在秘鲁伊基托斯采集的 9 份镜检阳性的恶性疟原虫样本中，有 8 份使用 HRP2 检测 RDT 检测结果为阴性或弱阳性。这些样本通过 PCR 检测 pfhrp2 和 pfhrp3 及其侧翼基因的存在情况，以及通过 ELISA 检测 HRP 蛋白的存在情况。为了调查 HRP 缺失寄生虫的地理范围及其时间发生情况，对秘鲁亚马逊地区不同地区采集的 148 份镜检阳性恶性疟原虫样本进行了回顾性研究。
这 9 个分离株中有 8 个缺乏 pfhrp2 和/或 pfhrp3 基因和一个或两个侧翼基因，ELISA 证实 HRP 缺失。回顾性研究表明，在 148 个样本中，有 61 个（41%）和 103 个（70%）分别缺乏 pfhrp2 或 pfhrp3 基因，其中 32 个（21.6%）样本缺乏两个 hrp 基因。
这是首次记录到恶性疟原虫现场分离株缺乏 pfhrp2 和/或 pfhrp3。在秘鲁亚马逊地区广泛分散的地区，不同缺乏 pfhrp2 和/或 pfhrp3 的寄生虫的高频和广泛分布，意味着针对 HRP2 的疟疾 RDT 将无法检测到秘鲁疟疾流行地区的很大一部分恶性疟原虫，不应使用。在该地区，应使用针对 HRP 的 RDT 检测寄生虫 LDH 或醛缩酶和质量显微镜进行疟疾诊断。迫切需要调查这些寄生虫在秘鲁和邻国的丰度和地理分布情况。
