英国的新研究发现，在控制新冠病毒传播这件事上，音量很关键。相比大喊大叫和高声唱歌，轻声讲话和唱歌产生的气溶胶总量要低得多，从而能降低新冠病毒传播风险。

Photo by Alyssa Yung on Unsplash

Sing softly and don’t shout to reduce the risk of Covid-19 spread, new research suggests, offering a ray of hope for musicians who have been restricted from performing in public.

新研究指出，轻声歌唱、不喊叫可以降低新冠病毒传播风险，这给那些被限制在公共场合表演的音乐家带来了一丝希望。

Music makers have been hit hard by the coronavirus pandemic, with singing, as well as playing of woodwind and brass instruments deemed to be a potential high risk for spreading the disease – a concern fuelled by outbreaks in choirs.

音乐家受疫情打击很严重，因为演唱以及吹奏木管和铜管乐器被视为传播新冠肺炎的潜在高危因素，合唱团暴发的聚集性病例加剧了这一担忧。

But the research offers hope to performers keen to get back on stage as soon as possible.

但是这项研究为那些想尽快回到舞台的表演者带来了希望。

"It is not about the vocalisation – whether it’s singing or speaking – it is about the volume,” said Jonathan Reid, a professor of physical chemistry at the University of Bristol and a co-author of the research. “Just by singing a little bit more softly you really reduce the risk.”

该研究的合著者、布里斯托大学物理化学系教授乔纳森·里德说：“无论是唱歌还是说话，都与发声方式无关，而是与音量有关。唱歌时稍微轻柔一些就能降低传播风险。”

In a study that has yet to be peer-reviewed, the team report how they asked 25 professional singers to breathe, speak, cough and sing into funnels. They then measured the mass of tiny droplets suspended in the air, known as aerosols, that were produced. The experiments were set up in an orthopaedic operating theatre, a setting chosen for its lack of background aerosols.

在一项尚未经过同行评议的研究中，研究团队请25名专业歌手对着漏斗状的器具呼吸、讲话、咳嗽和唱歌。然后他们测量了由此产生的气溶胶（在空气中悬浮的微小飞沫）的总量。实验在一个骨科手术室进行，选择这个环境是因为这里的气溶胶较少。

While one route by which Covid-19 spreads is via big droplets, largely produced when someone coughs and which fall to the ground within a couple of metres, Reid said aerosols were another possible route, noting such tiny droplets can linger in the air.

新冠病毒传播的一条路径是通过飞沫，大多是在某人咳嗽时产生，在一两米的距离内会落到地面。里德表示，气溶胶是另外一条可能的传播路径，他指出微小的飞沫会悬浮在空气中。

The team found the results of their study varied across participants, however at the lowest volume singing and speaking generated a similar mass of aerosols as breathing.

研究团队发现，参与者的结果各有不同，但是用最低音量唱歌和说话的人产生的气溶胶和呼吸时产生的气溶胶数量相近。

But when the team asked participants to recite Happy Birthday at different volumes, they found the loudest singing and speaking – 90-100dB – produced about 36 and 24 times the mass of aerosols respectively as generated by breathing.

但是当研究团队请参与者用不同音量唱《生日快乐》这首歌时，他们发现用最大音量（90到100分贝）唱歌和说话所产生的气溶胶分别是呼吸所产生的气溶胶的36倍和24倍。

"The volume of the activity, whether it is speaking or singing softly or speaking or singing loudly, that is really the main factor in governing the aerosol mass that is generated,” said Reid, adding that while singing generates a slightly higher mass of aerosols than speaking, at least when loud, the difference is very small compared with the effect of volume.

里德说：“无论是轻声讲话或唱歌还是大声讲话或唱歌，音量确实是决定产生的气溶胶总量的主要因素。”他补充道，尽管唱歌时产生的气溶胶总量比讲话时产生的气溶胶总量略高（至少在大声唱歌和讲话时是如此），二者区别和音量引起的区别相比微乎其微。

Co-author Declan Costello, an ear, nose and throat surgeon at Wexham Park hospital, noted other factors, including the size of the space and ventilation and duration of loud vocalisation, play an important role in potential infection risk.

研究报告的合著者、韦克斯汉姆公园医院的耳鼻喉外科医生德克兰·科斯特洛指出，空间大小、通风情况和高音量发声持续时间等其他因素对潜在感染风险也有重要影响。

In other words singing in a cathedral might pose a lower risk for spreading Covid-19 than shouting across a crowded pub. “Intuitively that would seem to be the case, assuming people are speaking or singing at the same sorts of volume,” said Costello.

换言之，在大教堂中唱歌相比在拥挤的酒馆中大叫造成的新冠病毒传播风险可能更低。科斯特洛说：“凭直觉来说是这样，假定人们讲话或唱歌的音量相等。”

However the research has limitations: it only measured aerosols produced by one individual at a time, while it did not look at how much virus was contained in the aerosol or the actual infection risk posed by the levels of aerosol produced.

但是这项研究也有局限性：它只测量了一个人一次性产生的气溶胶，没有测量气溶胶中所含的病毒数量，以及气溶胶引发的实际感染风险。

The team say their findings have already contributed to new guidance for England released on 15 August by the Department for Digital, Culture, Media & Sport.

研究团队称，他们的发现已经被数字、文化、媒体和体育部8月15日发布的英格兰（新冠防控）新指导意见收录。

英文来源：卫报

翻译&编辑：丹妮