在疟疾传播程度不同的环境中，疟疾高度敏感快速诊断检测的现场性能。

Field performance of the malaria highly sensitive rapid diagnostic test in a setting of varying malaria transmission.

机构信息

Medical Research Council Unit The Gambia at London School of Hygiene and Tropical Medicine, P.O. Box 273, Banjul, The Gambia.

MRC Centre for Global Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, Norfolk Place, London, W2 1P, UK.

出版信息

Malar J. 2019 Aug 27;18(1):288. doi: 10.1186/s12936-019-2929-1.

BACKGROUND

The Gambia has successfully reduced malaria transmission. The human reservoir of infection could further decrease if malaria-infected individuals could be identified by highly sensitive, field-based, diagnostic tools and then treated.

METHODS

A cross-sectional survey was done at the peak of the 2017 malaria season in 47 Gambian villages. From each village, 100 residents were randomly selected for finger-prick blood samples to detect Plasmodium falciparum infections using highly sensitive rapid diagnostic tests (HS-RDT) and PCR. The sensitivity and specificity of the HS-RDT were estimated (assuming PCR as the gold standard) across varying transmission intensities and in different age groups. A deterministic, age-structured, dynamic model of malaria transmission was used to estimate the impact of mass testing and treatment (MTAT) with HS-RDT in four different scenarios of malaria prevalence by PCR: 5, 15, 30, and 60%, and with seasonal transmission. The impact was compared both to MTAT with conventional RDT and mass drug administration (MDA).

RESULTS

Malaria prevalence by HS-RDT was 15% (570/3798; 95% CI 13.9-16.1). The HS-RDT sensitivity and specificity were 38.4% (191/497, 95% CI 34.2-42.71) and 88.5% (2922/3301; 95% CI 87.4-89.6), respectively. Sensitivity was the highest (50.9%, 95% CI 43.3-58.5%) in high prevalence villages (20-50% by PCR). The model predicted that in very low transmission areas (≤ 5%), three monthly rounds of MTAT with HS-RDT, starting towards the end of the dry season and testing 65 or 85% of the population for 2 consecutive years, would avert 62 or 78% of malaria cases (over 2 years), respectively. The effect of the intervention would be lower in a moderate transmission setting. In all settings, MDA would be superior to MTAT with HS-RDT which would be superior to MTAT with conventional RDT.

CONCLUSION

The HS-RDT's field sensitivity was modest and varied by transmission intensity. In low to very low transmission areas, three monthly rounds per year of MTAT with HS-RDT at 85% coverage for 2 consecutive years would reduce malaria prevalence to such low levels that additional strategies may achieve elimination. The model prediction would need to be confirmed by cluster-randomized trials.

背景

冈比亚已成功降低疟疾传播率。如果能够通过高度敏感、基于现场的诊断工具发现疟疾病例，并对其进行治疗，那么感染疟疾的人群数量将进一步减少。

方法

在 2017 年疟疾高发季节，我们在冈比亚的 47 个村庄进行了一项横断面调查。从每个村庄中随机抽取 100 名居民进行指尖采血，使用高度敏感的快速诊断检测（HS-RDT）和聚合酶链反应（PCR）检测疟原虫感染。我们对不同传播强度和不同年龄组中 HS-RDT 的敏感性和特异性进行了估计（以 PCR 为金标准）。我们使用确定性、年龄结构、疟疾传播动力学模型，根据 PCR 检测的疟疾流行率（5%、15%、30%和 60%）和季节性传播，在四种不同情况下估计了使用 HS-RDT 进行大规模检测和治疗（MTAT）的效果：5%、15%、30%和 60%。我们将其与使用常规 RDT 和大规模药物治疗（MDA）的 MTAT 进行了比较。

结果

HS-RDT 检测的疟疾患病率为 15%（570/3798；95%CI 13.9-16.1）。HS-RDT 的敏感性和特异性分别为 38.4%（191/497，95%CI 34.2-42.71）和 88.5%（2922/3301；95%CI 87.4-89.6）。在高流行地区（PCR 检测率为 20%-50%），敏感性最高（50.9%，95%CI 43.3-58.5%）。模型预测，在低传播区（≤5%），每年开展三轮、为期三个月的 MTAT，在旱季结束时开始，对 65%或 85%的人群进行连续两年的检测，每年将分别避免 62%或 78%的疟疾病例（持续两年）。在中度传播环境中，干预效果会降低。在所有环境中，MDA 都优于 HS-RDT 联合 MTAT，HS-RDT 联合 MTAT 优于常规 RDT 联合 MTAT。