How Coronavirus Infected Some, but Not All, in a Restaurant

广州早期病例揭示新冠病毒如何在餐厅传播

纽约时报双语版-广州早期病例揭示新冠病毒如何在餐厅传播

3月15日,在俄亥俄州酒吧和餐馆关门之前的最后一天,代顿市一家餐馆的空桌子。
Kyle Grillot for The New York Times

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In January, at a restaurant in Guangzhou, China, one diner infected with the novel coronavirus but not yet feeling sick, appeared to have spread the disease to nine other people. One of the restaurant’s air-conditioners apparently blew the virus particles around the dining room.

今年1月,在中国广州的一家餐厅里,一名感染了新冠病毒但并无不适的食客,似乎将其传给了另外9个人。显然是餐厅的其中一台空调,将病毒颗粒吹散到房间各处。

There were 73 other diners who ate that day on the same floor of the five-story restaurant, and the good news is they did not become sick. Neither did the eight employees who were working on the floor at the time.

当天,在这个五层楼餐厅的同一楼层,还有73名食客就餐,好在他们后来没有生病。当时在该层工作的8名员工也没有。

Chinese researchers described the incident in a paper that is to be published in the July issue of the Emerging Infectious Diseases, a journal published by the Centers for Disease Control and Prevention. The field study has limitations. The researchers, for example, did not perform experiments to simulate the airborne transmission.

中国研究人员在一篇论文中描述了该事件,论文将在美国疾病控制和预防中心出版的《新型传染病》(Infectious Diseases)杂志的7月号上发表。这项实地研究存在一定局限性。比如说,研究人员没有进行模拟空气传播的实验。

That outbreak illustrates some of the challenges that restaurants will face when they try to reopen. Ventilation systems can create complex patterns of air flow and keep viruses aloft, so simply spacing tables six feet apart — the minimum distance that the C.D.C. advises you keep from other people — may not be sufficient to safeguard restaurant patrons.

这个事件说明了餐厅在尝试重新营业时将面临的一些挑战。通风系统会产生复杂的气流,使病毒漂浮在空中,因此仅将桌子隔开六英尺——CDC建议人与人之间应该保持的最小间距——可能不足以保护餐厅顾客。

The social nature of dining out could increase the risk. The longer people linger in a contaminated area, the more virus particles they would likely inhale. Eating is also one activity that cannot be accomplished while wearing a mask. Virus-laden droplets can be expelled into the air through breathing and talking, not just through coughs and sneezes.

外出就餐的社交性质可能会增加风险。人们在受污染区域停留的时间越长,吸入的病毒颗粒可能就会越多。吃东西也是一项没法戴着口罩完成的活动。携带病毒的飞沫不仅可以通过咳嗽和打喷嚏,还可以通过呼吸和交谈进入空气。

As the C.D.C. now advises, “Avoid large and small gatherings in private places and public spaces, such a friend’s house, parks, restaurants, shops, or any other place.”

正如疾控中心的建议:“避免在私人和公共场所——例如朋友家、公园、餐馆、商店或任何其他地方——进行大小聚会。”

On the other hand, all of the people who became sick at the restaurant in China were either at the same table as the infected person or at one of two neighboring tables. The fact that people farther away remained healthy is a hopeful hint that the coronavirus is primarily transmitted through larger respiratory droplets, which fall out of the air more quickly than smaller droplets known as aerosols, which can float for hours.

另一方面,所有在中国餐馆生病的人要么与被感染者在同一张桌子上,要么坐在一两桌以外。离得较远的人没有患病,这也许可以说明,冠状病毒主要通过较大的呼吸飞沫传播,与体积较小、能在空气中漂浮数小时的气溶胶相比,飞沫会更快地掉落。

“I think it’s a well-done study with the limitations of being a field study,” said Werner E. Bischoff, the medical director of infection prevention and health system epidemiology at the Wake Forest School of Medicine in North Carolina. Dr. Bischoff was not involved with the research.

北卡罗来纳州威克森林医学院(Wake Forest School of Medicine in North Carolina)感染预防和卫生系统流行病学医学主任维尔纳·E·比绍夫(Werner E. Bischoff)说:“虽然实地研究存在局限性,但我认为这是一项做得很好的研究。”比绍夫未参与此项研究。

On Jan. 24, a family went to lunch at the restaurant in Guangzhou, a sprawling metropolis in southern China located 80 miles from Hong Kong.

1月24日,一家人在广州的一家饭店吃午餐。广州是中国南部一个繁华的大都市,距香港80英里。

The family had left Wuhan, 520 miles to the north and the hot spot of the initial coronavirus outbreak, one day before Chinese officials imposed a lockdown on the city and the surrounding province of Hubei to slow the spread of the disease.

这家人在武汉封城前一天离开了那座距离广州520英里的城市,也就是新冠病毒疫情最初暴发的热点,中国官员对那里及其所在的湖北省实施了封锁,以减缓传播。

At lunch, the five members of the family — designated Family A in the paper — appeared healthy. But later in the day, one of them, a 63-year-old woman, experienced a fever and a cough and went to the hospital where she tested positive for the coronavirus.

午餐时,这家人的五名成员——在报纸上被称为A家——看上去是健康的。但当天晚些时候,其中一名63岁的女性发烧、咳嗽,后到达医院进行新冠病毒检测,结果呈阳性。

Within two weeks, nine others who ate lunch on that floor of the Guangzhou restaurant that day also tested positive. Four were relatives of the first infected woman. They could have been infected outside of the restaurant.

两周之内,当天在该广州餐厅同一楼层进餐的9人检测也呈阳性。有四人是第一位受感染女性的亲戚。他们有可能是在餐厅外被感染的。

But for the other five, the restaurant appears to have been the source of the virus.

但是对于其他五人,餐厅似乎是该病毒的来源。

Family A’s table was on the west side of the 1,500-square foot dining room, between tables where two unrelated families, B and C, were also having lunch. Family B and Family A overlapped for a period of 53 minutes, and three of its members — a couple and their daughter — became sick. Family C sat next to Family A at the other neighboring table along the same side the room, overlapping for 73 minutes, and two of its members — a mother and her daughter — became ill.

A家的餐桌在这间1500平方英尺的餐厅的西侧,互不相识的B家和C家也正在邻桌吃午餐。B家和A家的用餐时间有53分钟的重叠,其中三名成员——一对夫妇和他们的女儿——后来患病。C家坐在A家在房间同一侧的另一个邻桌上,用餐时间重叠了73分钟,其中两个成员——母亲和女儿——后来患病。

An air-conditioning unit next to Family C blew air in the southward direction across all three tables; some of the air likely bounced off the wall, back in the direction of Family C.

C家旁边的一个空调的风向南吹向所有三个桌子;有些气流可能从墙壁反弹,朝着C家吹回来。

Because the coronavirus had not yet spread widely beyond Wuhan, public health officials were able to trace the recent contacts of Families B and C and determine that the restaurant was the only likely place where they would have crossed paths with the virus.

由于当时新冠病毒尚未在武汉以外广泛传播,因此公共卫生官员能够追溯到B家和C家近期的接触者,并确定这家餐馆是唯一可能与该病毒有接触的地方。

The researchers did not state in the paper whether any of the other diners who did not contract the coronavirus were members of the three affected families or if they were all customers at 12 other tables. The 73 people were quarantined for 14 days and did not develop symptoms.

研究人员没有在论文中陈述其他未感染新冠病毒的食客是否有来自这三个受影响的家庭,或者他们是否都属于其他12个餐桌的顾客。这73人被隔离了14天,没有出现症状。

“We conclude that in this outbreak, droplet transmission was prompted by air-conditioned ventilation,” the authors wrote. “The key factor for infection was the direction of the airflow.”

“我们得出的结论是,在这次疫情中,空调通风促使了飞沫传播,”作者写道。“感染的关键因素是气流的方向。”

Harvey V. Fineberg, who leads the Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats at the National Academies of Sciences, Engineering and Medicine, described the report as “provocative and eye-opening.”

国家科学工程和医学研究院新兴传染病和21世纪健康威胁常务委员会(Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats)主任哈维·V·芬伯格(Harvey V. Fineberg)形容这是一份“激动人心、很有启发”的报告。

He said restaurants should be mindful of the direction of airflow in arranging tables. Germicidal ultraviolet lights could also be installed to destroy floating virus particles, Dr. Fineberg said. And the paper’s findings could have implications beyond restaurants.

芬伯格说,餐厅在布置桌子时应注意气流的方向。他说,还可以安装杀菌紫外线灯来破坏漂浮的病毒颗粒。该论文的发现还可能对餐馆以外的其他领域产生影响。

“It’s illuminating for the kind of thing we need to keep learning about as we try to configure safe work spaces,” Dr. Fineberg said. “Not just safe restaurant and entertainment venues but where you go to work.”

“这提醒了我们在尝试配置安全的工作空间时需要持续学习的东西,”芬伯格说。“不仅是安全的餐厅和娱乐场所,还有你工作的地方。”