Coronavirus: Airborne transmission cannot be ruled out, WHO says

BBC NEWS

The World Health Organization has acknowledged there is emerging evidence that the coronavirus can be spread by tiny particles suspended in the air.

particle n. /ˈpɑːtɪkl/ a very small piece of sth 颗粒；微粒 •particles of dust 灰尘

•There was not a particle of evidence (= no evidence at all) to support the case. 没有丝毫支持这个论点的证据。

suspend v. /səˈspend/  

1.[ usually + adv./prep. ] ~ sth/sb (from sth) (by/on sth) to hang sth from sth else 悬；挂；吊 •Her body was found suspended by a rope. 人们发现她的尸体吊在绳子上。

2.to officially stop sth for a time; to prevent sth from being active, used, etc. for a time 暂停；中止；使暂停发挥作用（或使用等） •Production has been suspended while safety checks are carried out. 在进行安全检查期间生产暂停。

3.to officially delay sth; to arrange for sth to happen later than planned 延缓；暂缓；推迟 •The introduction of the new system has been suspended until next year. 新制度推迟到明年再行实施。

4.[ usually passive ] ~ sb (from sth) to officially prevent sb from doing their job, going to school, etc. for a time 使暂时停职（或停学等） •The police officer was suspended while the complaint was investigated. 投诉调查期间，这位警员被暂停职务。

5.be suspended in sth ( technical 术语 ) to float in liquid or air without moving 悬浮

The airborne transmission could not be ruled out in crowded, closed or poorly ventilated settings, an official said. If the evidence is confirmed, it may affect guidelines for indoor spaces. An open letter from more than 200 scientists had accused the WHO of underestimating the possibility of airborne transmission.

airborne transmission：空气传播   ventilate /ˈvɛntɪˌleɪt/  使通风，通风

The WHO has so far said that the virus is transmitted through droplets when people cough or sneeze.

droplet /ˈdrɒplɪt/ A droplet is a very small drop of liquid. 小滴 • Droplets of sweat were welling up on his forehead. 一颗颗小汗珠从他额头上不断冒出来。

"We wanted them to acknowledge the evidence," Jose Jimenez, a chemist at the University of Colorado who signed the paper, told the Reuters news agency.

Reuters /ˈrɔɪtəz/ 路透社

"This is definitely not an attack on the WHO. It's a scientific debate, but we felt we needed to go public because they were refusing to hear the evidence after many conversations with them," he said. WHO officials have cautioned the evidence is preliminary and requires further assessment.

Benedetta Allegranzi, the WHO's technical lead for infection prevention and control, said that evidence emerging of airborne transmission of the coronavirus in "crowded, closed, poorly ventilated settings that have been described, cannot be ruled out".

preliminary /prɪˈlɪmɪnəri/  N. ~ (to sth) a preliminary is an action or event that is done in preparation for sth 初步行动（或活动）；预备性措施 V.~ (to sth) happening before a more important action or event 预备性的；初步的；开始的·preliminary results/findings/enquiries 初步结果╱发现╱调查

 A shifting position?

Imogen Foulkes, BBC News in Geneva

For months, the WHO has insisted that Covid-19 is transmitted via droplets emitted when people cough or sneeze. Droplets that do not linger in the air, but fall onto surfaces - that's why handwashing has been identified as a key prevention measure.

emit /ɪˈmɪt/ V-T1. If something emits heat, light, gas, or a smell, it produces it and sends it out by means of a physical or chemical process. 发出; 散发 (热、光、气体或气味) 2.V-T To emit a sound or noise means to produce it. 发出 (声音或噪音)

But 239 scientists from 32 countries don't agree: they say there is strong evidence to suggest the virus can also spread in the air: through much tinier particles that float around for hours after people talk, or breathe out.

Today the WHO admitted there was evidence to suggest this was possible in specific settings, such as enclosed and crowded spaces.

That evidence will have to be thoroughly evaluated, but if it is confirmed, the advice on how to prevent the virus spreading may have to change, and could lead to more widespread use of masks, and more rigorous distancing, especially in bars, restaurants, and on public transport.

rigorous adj. /ˈrɪɡərəs/  

1.done carefully and with a lot of attention to detail SYN thorough 谨慎的；细致的；彻底的 •a rigorous analysis 细致的分析

2.demanding that particular rules, processes, etc. are strictly followed 严格的；严厉的