Lymphatic Filariasis Transmission and Elimination in Papua New Guinea

描述（由申请人提供）：在非洲、亚洲和太平洋地区的80个中低收入国家中，有超过10亿人面临淋巴丝虫病（LF）的风险。淋巴丝虫病是一种被忽视的热带病（NTD），它会导致象皮病、男性生殖器毁容和四肢疼痛肿胀。在过去10年中，全球一直在努力消除班氏杆菌（Wb）引起的LF，目标日期为2020年（世卫组织）。该战略依靠每年多次大量给药捐赠抗丝虫药（阿苯达唑加乙基卡马嗪或伊维菌素5-7年的大规模给药），目的是将血源性微丝虫病库减少到当地蚊子媒介持续传播所需的水平以下。然而，最近的观察表明，在许多地区，消灭LF的进展停滞不前，而且难以确定。这个应用程序将解决两个主要缺陷。首先是缺乏强有力的监测和评估方法，无法就以下问题做出知情决策：a)是否应继续或停止大规模预防接种，以及b)病媒控制措施（如长效杀虫剂处理过的蚊帐；LLIN）将如何利用大规模预防接种加速消灭疟疾。现有的国家消除乙肝病毒规划是基于世卫组织推荐的Binax快速卡片检测，该检测可检测血液中的成人乙肝抗原。虽然这种卡片检测快速方便，但与更敏感的寄生虫抗原特异性血清学检测相比，MDA检测后的假阳性和假阴性率往往较高。第二个缺陷是缺乏可靠的定量数据来评估使用LLIN和MDA结合媒介控制来减少LF传播的相对附加效益。在目前的应用中，我们结合了bbbb25年的经验和使用NIH同事提供的新抗原在巴布亚新几内亚（PNG）研究LF传播所获得的大量样本档案，以及最近在巴布亚新几内亚在疟疾和LF媒介相同的流行地区引入LLINs以控制疟疾。本研究a)描述了LF消除的关键变量和监测工具，b)利用MDA量化了LLIN对LF消除计划的影响，以及c)在LF消除监测期间将LF传播的昆虫学和人类标记联系起来。本研究测试的有效的LF消除监测工具和策略对于实现和维持巴布亚新几内亚的LF消除以及全球消除LF计划（GPELF）的2020年目标至关重要。

DESCRIPTION (provided by applicant): More than a billion people in 80 mid- and low-income countries of Africa, Asia and the Pacific are at risk for lymphatic filariasis (LF), a mosquito bore parasitic worm "Neglected Tropical Disease" (NTD) that causes elephantiasis, disfigurement of the male genitalia and painful swelling of the extremities. For the past 10 years there has been intense global effort to eliminate LF due to Wuchereria bancrofti (Wb) with a target date of 2020 (WHO). The strategy relies on repeated annual mass drug administration (MDA) of donated anti-filarial drugs (5-7 years of MDA with albendazole plus diethylcarbamazine or ivermectin) with the aim to reduce the reservoir of blood borne microfilaria (MF) below a level required for continuing transmission by local mosquito vectors. However, recent observations indicate that progress toward LF elimination is stalled and difficult to ascertain in many areas. This application will address two major deficiencies. The first is a lack of robust methods for monitoring and evaluation that allow for informed decision making with respect to a) whether MDA should be continued or stopped and b) how vector control measures (such as long lasting insecticide treated bednets; LLIN) will accelerate elimination using MDA. Existing national LF elimination programs are based on the WHO recommended Binax rapid card test, which detects adult Wb antigen in the blood. Although this card test is rapid and convenient, it often produces high false positive and false negative rates following MDA when compared to parasitological assays, more sensitive parasite-antigen specific serological assays. The second deficiency is lack of robust quantitative data assessing of the relative added benefit of combining vector control using LLIN with MDA to reduce LF transmission. In the current application we combine >25 years experience and access to a large archive of samples obtained in studying LF transmission in Papua New Guinea (PNG) using novel antigens provided by colleagues at NIH and the recent introduction of LLINs in PNG for malaria control in a endemic area where the vectors for malaria and LF are the same. This study a) characterizes the critical variables and monitoring tools for LF elimination, b) quantifies the impact of LLIN on LF elimination programs using MDA, and c) links entomological and human markers of LF transmission during LF elimination monitoring. Effective LF elimination monitoring tools and strategies as tested in this study are essential to achieving and maintaining LF elimination in PNG and the stated 2020 goals of the Global Program for the Elimination of LF (GPELF).