Changing Epidemiology of South Asian Malaria

项目1总结： 南亚东北走廊有恶性疟原虫高水平、致病水平高的地区， 以及高水平的药物失效。与之形成鲜明对比的是，印度南部地区仍以P。 间日疟原虫。在这些地区，疟疾的报告似乎更为良性。有趣的是，年疟疾病例的概况 印度中部正在迅速变化，因此提供了一个非同寻常的机会来研究可能 推动了疟疾的进化。 印度中部恶性疟原虫水平较高的最明显解释是 寄生虫菌株正在从“源”位置(涉及高毒力)转移到新的“下沉”位置，这 历史上表现出更多的良性间日疟原虫感染。另一种更耐人寻味的解释是， 寄生虫“不需要移动；由特定基因编码的特定毒力特征可以通过 跨地区的重组。获得新毒力特征的本地寄生虫可能会竞争更多 有效对抗当地间日疟原虫种群。为了调查这一点，项目1的一个总体目标 是系统和仔细地确定南亚恶性疟原虫和间日疟原虫的种群结构。一个 第二个总体目标是确定寄生虫的详细基因分型分析是否允许我们将寄生虫 基因类型对特定疾病结果的影响。

PROJECT 1 SUMMARY: The north-east corridor of South Asia has regions with high level of P. falciparum, high levels of pathogenesis, and high levels of drug failures. In complete contrast, southern regions of India still carry predominantly P. vivax. In these regions malaria presentations appear more benign. Interestingly, profiles of malaria cases in central India are changing rapidly thus providing an extraordinary opportunity to study the factors that may be driving the evolution of malaria. The most obvious explanation for higher levels of P. falciparum in central India is that specific parasite strains are moving from "source" sites (involving high levels of virulence) to new "sink" sites, which historically presented more benign P. vivax infections. Another, more intriguing explanation is that the "whole parasite" does not need to move; specific virulence traits, coded by specific genes, may propagate by recombination across regions. Local parasites that have acquired new virulence traits may compete more effectively against local P. vivax parasite populations. In order to investigate this, one general goal of Project 1 is to systematically and carefully define the population structures of P. falciparum and P. vivax in South Asia. A second general goal is to determine if detailed genotypic analysis of parasites allow us to correlate parasite genotypes to specific disease outcomes.