中   文










发布时间:2020-06-17 作者:admin 点击:100

Up to 45 percent of SARS-CoV-2 infections may be asymptomatic



上海译锐翻译       2020-6-16     09:46 a.m.

An extraordinary percentage of people infected by the virus behind the ongoing deadly COVID-19 pandemic never show symptoms of the disease, according to the results of a Scripps Research analysis of public datasets on asymptomatic infections.

根据斯科瑞普斯研究所(Scripps Research)对无症状感染公共数据的分析结果,在目前感染有致命风险的COVID-19传染病病毒的人群中,有很大一部分感染者并未出现任何感染症状。

asymptomatic infection:无症状感染

The findings, published in Annals of Internal Medicine, suggest that asymptomatic infections may account for as much as 45 percent of all COVID-19 cases, playing a significant role in the early and ongoing spread of COVID-19. The report highlights the need for expansive testing and contact tracing to mitigate the pandemic.

研究结果刊登于《内科医学年监》(Annals of Internal Medicine)。根据研究报告,在所有的COVID-19病例中,无症状感染者的比例大概高达45%。如此高的比例在COVID-19早期以及持续传播方面具有重要的推动作用。报告强调,延缓疾病传播需要进行大规模的检测以及接触人群追踪。

"The silent spread of the virus makes it all the more challenging to control," says Eric Topol, MD, founder and director of the Scripps Research Translational Institute and professor of Molecular Medicine at Scripps Research. "Our review really highlights the importance of testing. It's clear that with such a high asymptomatic rate, we need to cast a very wide net, otherwise the virus will continue to evade us."

Eric Topol,医学博士,斯科瑞普斯研究所转化研究所创始人兼所长、斯科瑞普斯分子药物教授表示:“悄无声息地传播使病毒更加难以控制。我们的报告强调了检测的重要性。面对如此高比例的无症状感染,显然我们需要布下天罗地网,否则病毒还会继续和我们玩捉迷藏。”

Together with behavioral scientist Daniel Oran, Topol collected information from testing studies on 16 diverse cohorts from around the world. These datasets -- gathered via keyword searches of PubMed, bioRxiv and medRxiv, as well as Google searches of relevant news reports -- included data on nursing home residents, cruise ship passengers, prison inmates and various other groups.

Topol和行为学家Daniel Oran一道从世界各地16个分散的人群的测试研究中收集信息。这些数据集来自于通过关键词“PubMed、bioRxiv和medRxiv”搜索以及通过Google搜索相关新闻报道,包括养老院人群、邮轮乘客、监狱罪犯以及各种其他群体的数据搜索结果。


"What virtually all of them had in common was that a very large proportion of infected individuals had no symptoms," says Oran. "Among more than 3,000 prison inmates in four states who tested positive for the coronavirus, the figure was astronomical: 96 percent asymptomatic."


The review further suggests that asymptomatic individuals are able to transmit the virus for an extended period of time, perhaps longer than 14 days. The viral loads are very similar in people with or without symptoms, but it remains unclear whether their infectiousness is of the same magnitude. To resolve that issue, we'll need large-scale studies that include sufficient numbers of asymptomatic people.

报告进一步表明,无症状感染者能够在更长的时间内传播病毒,也许不止14天。有症状感染者或无症状感染者身体中的病毒载量非常相似,但是其感染程度是否具有相同等级则仍不明确。为了解决这一问题,我们需要展开大规模的研究,其中包括足够多的无症状感染者 。

viral load:病毒载量/病毒负荷

The authors also conclude that the absence of symptoms may not imply an absence of harm. CT scans conducted on 54 percent of 76 asymptomatic individuals on the Diamond Princess cruise ship, appear to show significant subclinical lung abnormalities raising the possibility of SARS-CoV-2 infection impacting lung function that might not be immediately apparent. The scientists say further research is needed to confirm the potential significance of this finding.



The authors also acknowledge that the lack of longitudinal data makes distinguishing between asymptomatic and presymptomatic individuals difficult. An asymptomatic individual is someone who is infected with SARS-CoV-2, but never develops symptoms of COVID-19, while a presymptomatic person is similarly infected, but will eventually develop symptoms. Longitudinal testing, which refers to repeated testing of individuals over time, would help differentiate between the two.


"Our estimate of 40 to 45 percent asymptomatic means that, if you're unlucky enough to get infected, the probability is almost a flip of a coin on whether you're going to have symptoms. So to protect others, we think that wearing a mask makes a lot of sense," Oran concludes.


来源:科学日报     编辑:质控部