基于学校的治疗。图片来源Anna Phillips

This blog post is part of a series featuring new articles published in thelcntdrCollection: Advances in scientific research for NTD control，，，，由London Centre for Neglected Tropical Disease Research（lcntdr）。请继续关注Twitter上的更新@bugbittentweetsand@NTDResearch。您可以在系列中找到其他帖子here。

血吸虫病

血吸虫病是由生活在淡水中的寄生虫引起的。它也被称为比尔哈兹（Bilharzia）（在首次发现成年蠕虫后的西奥多·比尔哈兹（Theodor Bilharz）之后），蜗牛发烧（中间宿主是淡水蜗牛）或游泳者的瘙痒（由于蠕虫进入皮肤的皮疹是由于皮疹进入皮肤）。血吸虫病是仅次于疟疾的非洲第二大流行的热带疾病。尽管没有在疟疾的程度上杀死，但血吸虫病可能导致慢性疲劳，贫血，身体和认知阻滞，器官损伤和致命状况，例如膀胱癌以及增加艾滋病毒/艾滋病的易感性。

It is difficult to know how many individuals die of schistosomiasis each year because death certificates seldom identify schistosomiasis as the primary cause of death. The prognosis is very good with early treatment, but people can die if it is left untreated. Unfortunately, schistosomiasis is often left undetected for several years. In fact, cyclist Chris Froome was not diagnosed until a blood test in 2010, the treatment of which may have helped his Tour de France win in 2013! The severity of the disease depends on the number of worms and how long the person has been infected.

Mass drug administration

Mass drug administration (MDA) is a strategy used to deliver medicine to the entire at-risk population of an area, most commonly a district. MDA with praziquantel is the main strategy for schistosomiasis control. In 2001, the World Health Organization (WHO) developed a “dose pole” for the administration of praziquantel, which estimates the optimal dosage according to an individual’s height. This invention has enormously facilitated the administration of the drug in large-scale interventions where whole communities are treated en masse by the local health worker.

学校的治疗或社区范围的治疗

In Niger and most African settings, the control strategy is school-based treatment (SBT) with praziquantel, following the WHO guidelines. The rationale for this approach is that school-aged children harbor the burden of schistosomiasis infections due to their higher recreational water contact in rivers and ponds. There is a growing body of evidence regarding the burden of infection in adults and their potential role in sustaining transmission, which suggests a need for them to be included in treatment programs. There is debate around whether there is a cost-benefit to expanding treatment to community-wide treatment (CWT) and how to juggle this conundrum with a global shortage of praziquantel, which could not support countries worldwide scaling SBT up to CWT.

这项研究reviewed which treatment strategy provided the greatest reduction of schistosomiasis over five years comparing SBT once a year, SBT twice a year and SBT using test & treat (no MDA), CWT once a year and CTW twice a year (see figure).

这产生了五个主要发现：

1. 感染的开始率将决定该策略: In areas of high prevalence (i.e. a lot of infection in a community) treatment in schools twice a year was more impactful than treatment every year. In low prevalence settings there was no significant effect on treatment frequency.
2. Adults benefit indirectly from treatment of school-aged children only: Adults tested in the annual SBT group also showed a decrease in schistosomiasis infection across the five years.
3. Adults should be included in the monitoring and evaluation of schistosomiasis programs：这些结果表明，对学龄儿童的监测和评估并不是成人感染负担的成功指标，社区广泛治疗的理由应包括成年人进行评估调查。
4. 仅治疗不足以消除血吸虫病：在低患病率环境中两轮治疗缺乏统计影响，表明可能仅通过治疗来破坏传播，并使用其他策略，例如健康教育，水，卫生和卫生（WASH）和蜗牛控制，也应该考虑。
5. 覆盖范围和合规性的准确性是具有挑战性的，但成功的关键: The success of schistosomiasis control is dependent on high treatment coverage and compliance. Average treatment coverage in this study was well above the WHO 75% threshold, in some areas above 100%, which is not uncommon for control programs to report. This highlights the need for control programs to be scrupulous in getting a reliable denominator. Furthermore, even when the proportion of the targeted population receiving treatment is high (coverage), those ingesting all the tablets (compliance) may be a better indicator of how well MDA is implemented.

These findings are an important consideration for schistosomiasis control programs that are considering elimination and support the idea that scaling up the frequency of treatment rounds, particularly in areas of low prevalence, will not eliminate schistosomiasis. The finding that prevalence in the community can be reduced, even where only school children are being treated, could have logistical and cost-saving implications for the national control programs.

此博客文章中的研究刚刚在lcntdrCollection: Advances in scientific research for NTD control，，，，由London Centre for Neglected Tropical Disease Research（lcntdr）。该系列已经publishing in寄生虫和向量since 2016, and releasing new articles periodically. This series features recent advances in scientific research for NTDs executed by LCNTDR member institutions and their collaborators. It aims to highlight the wide range of work being undertaken by the LCNTDR towards achieving the United Nations Sustainable Development Goals as well as supporting the objectives of the World Health Organization road map for neglected tropical disease 2021-2030.

LCNTDR于2013年启动，目的是为NTD提供重点的运营和研究支持。LCNTDR，联合计划自然历史博物馆， 这伦敦卫生与热带医学学院， 这皇家兽医学院， 这Partnership for Child Development， 这SCI基金会（（formerly known as the Schistosomiasis Control Initiative) and伦敦帝国学院，进行跨学科研究，以建立围绕NTD计划的设计，实施，监视和评估的证据基础。

您可以在系列中找到其他帖子here。