The study concluded that 86 per cent of cases were “undocumented” – that is, asymptomatic or had only very mild symptoms (Science, doi.org/ggn6c2). The researchers also analysed case data from foreign nationals who were evacuated from the city of Wuhan, where the first cases were seen, and found a similar proportion of asymptomatic or very mild cases.
Such undocumented cases are still contagious and the study found them to be the source of most of the virus’s spread in China before the restrictions came in. Even though these people were only 55 per cent as contagious as people with symptoms, the study found that they were the source of 79 per cent of further infections, due to there being more of them, and the higher likelihood that they were out and about.
“If somebody’s experiencing mild symptoms, and I think most of us can relate to this, we’re still going to go about our day,” says Shaman. “These people are the major driver of it and they’re the ones who facilitated the spread.”
Read more: https://www.newscientist.com/article/2238473-you-could-be-spreading-the-coronavirus-without-realising-youve-got-it/#ixzz6HmhKYLbR
この研究では、症例の86％が「未記録」、つまり無症状または非常に軽い症状しかなかったと結論づけた（Science, doi.org/ggn6c2）。 研究者らはまた、最初の症例が見られた武漢市から避難してきた外国人の症例データを分析したところ、同様の割合で無症状または非常に軽度の症例が見られた。
このような不法滞在者は今でも感染しており、この研究では、規制が導入される前の中国では彼らがウイルスのほとんどの感染源であったことが判明した。 これらの人々は、症状のある人々と比べて55％しか感染しなかったにもかかわらず、研究では、彼らの数が多く、彼らが外出している可能性が高いため、彼らがさらなる感染の79％の源であることが判明しました。
"誰かが軽度の症状を経験していても、私たちのほとんどがこのことに共感できると思いますが、私たちは毎日を過ごすことになります。 "これらの人々が主な推進者であり 拡散を促進したのです"
続きを読む: https://www.newscientist.com/article/2238473-you-could-be-spreading-the-coronavirus-without-realising-youve-got-it/#ixzz6HmhKYLbR
BCG vaccination effect
