Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK.
Parasit Vectors. 2018 Jun 15;11(1):349. doi: 10.1186/s13071-018-2900-y.
In West and Central Africa, there is a need to establish the prevalence of Wuchereria bancrofti in areas that are co-endemic for Loa loa, in order to implement the appropriate strategies to scale-up interventions for the elimination of lymphatic filariasis (LF). Due to the risk of severe adverse events (SAEs) to ivermectin in individuals with high L. loa microfilaraemia, the current strategy recommended by the World Health Organization (WHO) is twice yearly mass drug administration (MDA) with albendazole, supplemented by vector control targeting the Anopheles vectors. Defining W. bancrofti prevalence in areas co-endemic with L. loa is complicated by the cross-reactivity of rapid diagnostic immunochromatographic card tests (ICT), widely used for LF mapping, in individuals with high L. loa microfilaraemia. This has probably resulted in the overestimation of LF prevalence, triggering the implementation of MDA strategies, which may be unnecessary and wasteful of the limited resources for elimination programme implementation. Here we review the literature and present historical evidence, which uniformly highlight low or no prevalence of W. bancrofti infection and/or clinical LF cases across five Central African countries, in more than 30 different geographical areas covering 280 individual sites and > 22,000 individuals tested within high risk L. loa areas. This highlights the very limited information available on LF prevalence in L. loa areas, and potentially has major policy implications, which could shift the focus towards revised mapping criteria to verify low or no W. bancrofti prevalence in high risk L. loa areas. In this situation, revising the current WHO strategy from MDA, to focus more on ensuring high and effective vector control, through insecticide treated/long-lasting impregnated bednets (ITNs/LLINs), integration of point-of-care test-and-treat options into health systems, and consolidating closer links with the malaria control programme may be a more effective and appropriate use of the limited resources and drug donations available for LF elimination.
在西非和中非，需要确定在同时流行罗阿罗阿和班氏丝虫的地区中班氏丝虫的流行情况，以便实施适当的策略，扩大消除淋巴丝虫病（LF）的干预措施。由于伊维菌素在高微丝蚴血症的罗阿罗阿感染个体中存在严重不良事件（SAE）的风险，世界卫生组织（WHO）目前推荐的策略是每年两次用阿苯达唑进行大规模药物治疗（MDA），辅以针对疟疾病媒的病媒控制。在同时流行罗阿罗阿的地区中确定班氏丝虫的流行情况很复杂，因为快速诊断免疫层析卡检测（ICT）具有交叉反应性，广泛用于 LF 绘图，在高微丝蚴血症的个体中。这可能导致 LF 流行率的高估，从而引发 MDA 策略的实施，而这些策略可能是不必要的，并且浪费了消除计划实施的有限资源。在这里，我们回顾了文献并提出了历史证据，这些证据一致强调了在五个中非国家的 30 多个不同地理区域的 280 个不同地点和超过 22000 名测试个体中，班氏丝虫感染和/或临床 LF 病例的低流行率或无流行率。这突出了在罗阿罗阿地区 LF 流行率方面可用的信息非常有限，并且可能具有重大政策意义，这可能会将重点转移到修订的绘图标准上，以验证高风险罗阿罗阿地区的低或无班氏丝虫流行率。在这种情况下，修订当前的 WHO 策略，从 MDA 转变为更注重确保高有效的病媒控制，通过使用驱虫处理/长效浸渍蚊帐（ITNs/LLINs）、将即时检测和治疗选项整合到卫生系统中，以及加强与疟疾控制计划的紧密联系，可能是对有限的资源和药物捐赠的更有效和更合适的利用，以实现 LF 的消除。
