小柯机器人

英国剑桥大学Henrik Salje研究团队评估了Dengvaxia疫苗对有症状和亚临床登革热感染的延长效力。2021年6月24日出版的国际知名学术期刊《自然-医学》杂志发表了这一成果。

他们展示了一项 III 期疫苗研究的辅助研究结果 (n = 611)。所有参与者都接受了三剂 Dengvaxia 或安慰剂，并随访了 6 年。他们对年度样本和确认的登革热发作期间进行了中和测试（n = 16,508 次总测量值）。他们使用数学模型来重建对疫苗接种和自然感染的长期抗体反应，并识别亚临床感染。报告了 87 例有症状的感染，他们估计还有 351 例亚临床感染。

尽管疫苗的保护作用集中在疫苗接种后的前 3 年，但累积疫苗效力对于亚临床和症状感染均呈阳性。在具有相同抗体滴度的个体中，他们发现安慰剂和疫苗接受者之间随后感染或疾病的风险没有差异，这表明抗体滴度是保护和疾病风险的良好预测指标。

研究人员表示，世界上一半以上的人口生活在有登革热病毒感染风险的地区。疫苗对于控制传播至关重要，但是，唯一获得许可的疫苗 Dengvaxia 已被证明会增加一部分个体患严重疾病的风险。由于对抗体反应（包括疫苗产生的反应）以及抗体滴度是否可以用作预防感染或疾病的标志物的了解不足，疫苗工作受到阻碍。

附：英文原文

Title: Evaluation of the extended efficacy of the Dengvaxia vaccine against symptomatic and subclinical dengue infection

Author: Henrik Salje, Maria Theresa Alera, Mary Noreen Chua, Taweewun Hunsawong, Damon Ellison, Anon Srikiatkhachorn, Richard G. Jarman, Gregory D. Gromowski, Isabel Rodriguez-Barraquer, Simon Cauchemez, Derek A. T. Cummings, Louis Macareo, In-Kyu Yoon, Stefan Fernandez, Alan L. Rothman

Issue&Volume: 2021-06-24

Abstract: More than half of the world’s population lives in areas at risk for dengue virus infection. A vaccine will be pivotal to controlling spread, however, the only licensed vaccine, Dengvaxia, has been shown to increase the risk of severe disease in a subset of individuals. Vaccine efforts are hampered by a poor understanding of antibody responses, including those generated by vaccines, and whether antibody titers can be used as a marker of protection from infection or disease. Here we present the results of an ancillary study to a phase III vaccine study (n=611). All participants received three doses of either Dengvaxia or placebo and were followed for 6years. We performed neutralization tests on annual samples and during confirmed dengue episodes (n=16,508 total measurements). We use mathematical models to reconstruct long-term antibody responses to vaccination and natural infection, and to identify subclinical infections. There were 87 symptomatic infections reported, and we estimated that there were a further 351 subclinical infections. Cumulative vaccine efficacy was positive for both subclinical and symptomatic infection, although the protective effect of the vaccine was concentrated in the first 3years following vaccination. Among individuals with the same antibody titer, we found no difference between the risk of subsequent infection or disease between placebo and vaccine recipients, suggesting that antibody titers are a good predictor of both protection and disease risk.

DOI: 10.1038/s41591-021-01392-9

Source: https://www.nature.com/articles/s41591-021-01392-9

Nature Medicine：《自然—医学》，创刊于1995年。隶属于施普林格·自然出版集团，最新IF：87.241
官方网址：https://www.nature.com/nm/
投稿链接：https://mts-nmed.nature.com/cgi-bin/main.plex