Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College London, Norfolk Place, London W2 1PG, UK.
Nature. 2015 Dec 3;528(7580):S86-93. doi: 10.1038/nature16039.
The global burden of malaria has been substantially reduced over the past two decades. Future efforts to reduce malaria further will require moving beyond the treatment of clinical infections to targeting malaria transmission more broadly in the community. As such, the accurate identification of asymptomatic human infections, which can sustain a large proportion of transmission, is becoming a vital component of control and elimination programmes. We determined the relationship across common diagnostics used to measure malaria prevalence - polymerase chain reaction (PCR), rapid diagnostic test and microscopy - for the detection of Plasmodium falciparum infections in endemic populations based on a pooled analysis of cross-sectional data. We included data from more than 170,000 individuals comparing the detection by rapid diagnostic test and microscopy, and 30,000 for detection by rapid diagnostic test and PCR. The analysis showed that, on average, rapid diagnostic tests detected 41% (95% confidence interval = 26-66%) of PCR-positive infections. Data for the comparison of rapid diagnostic test to PCR detection at high transmission intensity and in adults were sparse. Prevalence measured by rapid diagnostic test and microscopy was comparable, although rapid diagnostic test detected slightly more infections than microscopy. On average, microscopy captured 87% (95% confidence interval = 74-102%) of rapid diagnostic test-positive infections. The extent to which higher rapid diagnostic test detection reflects increased sensitivity, lack of specificity or both, is unclear. Once the contribution of asymptomatic individuals to the infectious reservoir is better defined, future analyses should ideally establish optimal detection limits of new diagnostics for use in control and elimination strategies.
在过去的二十年中，全球疟疾负担已大大减轻。未来进一步减少疟疾的努力将需要超越对临床感染的治疗，而更广泛地针对社区中的疟疾传播。因此，准确识别无症状的人类感染，这些感染可以维持很大一部分传播，已成为控制和消除规划的重要组成部分。我们基于对横断面数据的汇总分析，确定了用于衡量疟疾流行率的常见诊断方法-聚合酶链反应（PCR），快速诊断测试和显微镜之间的关系，以检测流行地区的恶性疟原虫感染。我们比较了快速诊断测试和显微镜检测，包括来自超过 170,000 个人的数据，而比较快速诊断测试和 PCR 检测的则有 30,000 个数据。分析表明，平均而言，快速诊断测试检测到 41％（95％置信区间= 26-66％）的 PCR 阳性感染。在高传播强度和成人中比较快速诊断测试与 PCR 检测的数据很少。快速诊断测试和显微镜测量的患病率相当，尽管快速诊断测试检测到的感染略多于显微镜。平均而言，显微镜捕获了 87％（95％置信区间= 74-102％）的快速诊断测试阳性感染。快速诊断测试检测率较高反映了敏感性增加，特异性缺乏还是两者兼而有之，尚不清楚。一旦更好地定义了无症状个体对传染性储库的贡献，未来的分析就应理想地确定新诊断方法在控制和消除策略中的最佳检测限。
