Defining the biomedical, environmental and social risk factors for human infection with Plasmodium knowlesi; opportuniti

疟疾是由一种主要生活在宿主血液中的单细胞寄生虫引起的，并通过雌蚊的叮咬在宿主之间传播。直到最近，人类才被认为是4种不同疟疾寄生虫的天然宿主;超过100种疟疾寄生虫存在并感染许多不同的动物。2004年，在马来西亚婆罗洲，一种寄生虫引起了人类疟疾的爆发，这种寄生虫以前只在东南亚的某些类型的猕猴中发现。这个物种是诺氏疟原虫，虽然在其自然宿主猴子中是良性的，但它在一小部分人类患者中引起严重甚至致命的疾病。目前，很难评估这种明显的宿主转换可能对公共卫生造成的潜在威胁。我们对人类携带诺氏疟原虫的比例知之甚少，对这种寄生虫在其天然猴子宿主中的流行程度也知之甚少。同样，我们需要调查为什么负责传播诺氏疟原虫的特定蚊子既叮咬猴子又叮咬人类。环境和社会因素可能导致某些人群，如林业工人，面临更大的诺氏疟原虫感染风险。这些因素也是不确定的，使得预防和控制措施不可能付诸实践。我们建议通过建立一个由来自英国和受诺氏疟原虫影响的东南亚地区的生物医学，环境和社会科学学科的研究人员组成的网络来填补我们对人类诺氏疟原虫感染知识的空白。我们的目标是：收集和分析菲律宾实地工作的初步数据，为更广泛的研究战略提供信息。将从人类和蚊子身上收集样本，用于检测诺氏疟原虫DNA，土地使用绘图和问卷调查将帮助我们查明感染的风险因素。由于伦敦卫生和热带医学学院与菲律宾研究所之间现有的联系，菲律宾地区将是最初的重点。为研究的所有合作者和潜在最终用户举办研讨会，正式确定研究策略，管理结构和完整的网络。在实地初步结果的帮助下，将在赠款期间制定关键的研究问题，其目的是为人类诺氏疟原虫的区域性研究提出更大的赠款申请。

The disease malaria is caused by a single celled parasite that lives predominantly in the blood of its host, and is transmitted between hosts by the bite of a female mosquito. Humans were thought, until recently, to be the natural hosts for 4 different species of malaria parasite; greater than 100 species exist and infect many different animals. In Malaysian Borneo, 2004, an outbreak of malaria in humans resulted from a parasite species that had previously been found only in certain types of macaque in Southeast Asia. This species is Plasmodium knowlesi and, although benign in its natural monkey host, it caused severe and even fatal disease in a small proportion of human sufferers. Currently, it is difficult to assess the potential threat to public health that might result from the apparent host switch. We know little about the proportion of humans carrying Plasmodium knowlesi and less about the prevalence of the parasite in its natural monkey host. Similarly, we need to investigate the reasons why the particular mosquito responsible for transmitting Plasmodium knowlesi bites both monkeys and humans. Environmental and social factors may lead to certain groups of people, such as forest workers, being at greater risk of Plasmodium knowlesi infection. These factors are also undefined, making prevention and control measures impossible to put into practice.We propose to fill the gaps in our knowledge of human Plasmodium knowlesi infections by building a network of researchers from biomedical, environmental, and social science disciplines, both from the UK and regions of Southeast Asia affected by Plasmodium knowlesi. Our objectives are:To collect and analyse preliminary data from fieldwork in the Philippines with which to inform a broader research strategy. Samples will be collected from humans and mosquitoes for the detection of Plasmodium knowlesi DNA, and land-use mapping and questionnaires will help us to pinpoint risk factors for infection. Areas of the Philippines will be the initial focus due to existing links between the London School of Hygiene and Tropical Medicine and Philippine institutes. To hold a workshop for all collaborators and potential end-users of the study in which a research strategy, management structure and full network is formalised. Helped by preliminary results from the field sites, key research questions will be developed during the grant period, the aim of which is to produce a larger grant application for the regional wide study of Plasmodium knowlesi in humans.