WHO专家组组长如何看待中国“全民抗疫”

原文题目：Inside China's All-out War on Coronavirus

作者：Donald G. McNeil Jr. (科学栏目记者，负责报导传染病和贫困地区的疾病新闻。他于1976年加入《纽约时报》，并在60个地区展开报导。)

发表时间：2020年3月4日

布鲁斯·艾尔沃德博士是赴华评估中国冠状病毒防疫工作的世界卫生组织专家组组长。

作为世界卫生组织专家组此次中国之行的组长，布鲁斯·艾尔沃德博士(Bruce Aylward)感觉自己已经登上过巅峰——看到了应对的可能性。

在2月的一次为期两周的访问中，艾尔沃德看到了中国如何迅速遏制一场吞没武汉、对全国各地构成威胁的冠状病毒暴发。

中国的新增病例已经从2月初的每天3000多例降至约200例。随着中国经济活动的恢复，这一数字可能再次上升。但就目前而言，世界其他地方出现的新病例要多得多。

艾尔沃德说，中国的抗疫方式可以被复制，但这需要速度、资金、想象力和政治勇气。

迅速采取行动的国家仍可能控制住疫情，「因为这还不是全球性的流行病——而是全球都有疫情暴发，」他补充说。

艾尔沃德拥有30年抗击小儿麻痹症、伊波拉病毒和其他全球卫生突发事件的经验，在接受《纽约时报》采访时，他详细介绍了他认为抗击这种病毒的行动应该如何开展。

以下对话经过了编辑和精简。

Q: 我们知道这种病毒的致死率是多少吗？我们听到一些人估计它接近1918年导致2.5%患者死亡的西班牙流感，而另一些人则认为它比导致0.1%患者死亡的季节性流感稍微严重一些。遗漏病例数量可能会影响这一数据。

西方国家对无症状病例有很大的恐慌。许多人在测试时没有症状，但在一两天内就出现了。

在广东，他们重新检测了32万份原本用于流感监测和其他筛查的样本。不到0.5%的人呈阳性，这个数字与该省已知的1500例Covid病例大致相同。（Covid-19是由冠状病毒引起的疾病的学名。）

没有证据表明我们看到的只是冰山一角，还有十分之九的冰山是传播病毒的隐藏殭尸。我们现在看到的就是一个金字塔：大部分都在地面上了。

等到我们可以测试许多人的抗体时，也许我会说，「你猜怎么着？这些数据并没有告诉我们真相。」但我们现有的数据并不支持这一说法。

Q:如果无症状传播很少，那是好事。但糟糕的是，这意味着我们所看到的死亡率——从中国部分地区的0.7%到武汉地区的5.8%——是正确的，对吧？

我听过这种说法：「死亡率不是很难看，因为实际上轻症病例要多的多。」但抱歉，死亡人数还是一样多。实际病死率可能跟湖北省外的统计差不多，就在1%到2%之间。

Q: 儿童情况如何？我们知道他们中很少有住院患者。但他们会被感染吗？会传染给家人吗？

我们还不知道。广东省的调查也显示，20岁以下人群几乎没有感染。儿童会得流感，但不会感染这个病毒。至于他们是否感染了但不受影响，是否会传给家人，我们必须做更多研究。但我问了几十位医生：你是否见过儿童作为主要病例的传播链？答案是否定的。

Q: 为什么？有一种理论认为，青少年经常感染已知的四种轻度冠状病毒，从而得到了保护。

这仍然是个推测。我无法得到足够的共识，因此也没有写进世界卫生组织报告。

Q: 这是否意味着关闭学校毫无意义？

不是的。还是有不确定的地方。如果一种疾病是危险的，而且我们看到了聚集性疫情，那就必须关闭学校。我们知道这会造成问题，因为你一旦把孩子送回家，你家一半的劳动力就得待在家里照顾他们。但你不能拿孩子冒险。

Q: 中国的病例真的在减少吗？

我知道有人怀疑，但在我们去过的每家检测诊所，人们都会说，「现在和三周前不一样了。」疫情峰值时每天有4.6万人要求做检测；当我们离开时，变成了每天1.3万人。医院都有空病床了。

我看不出任何操纵数据的迹象。迅速暴发的疫情已经稳定下来，而且降温的速度比预期要快。粗略计算下来，有数十万中国人因为这种严厉的应对措施而免于罹患Covid-19。

Q: 这种病毒会像新型流感那样，感染几乎所有人吗？

不会——75%到80%的聚集性疫情都是家庭传播。你可能在医院、餐馆或监狱得上，但绝大多数都是在家庭传播中感染的。而且只有5%到15%的近距离接触者会患病。所以他们会尽快把你和你的亲戚隔离开来，并在48小时内找出所有你接触过的人。

Q: 你说不同的城市有不同的反应。为什么？

这取决于他们是否出现零病例、零星病例、聚集性疫情或是广泛传播。

首先，你必须确保每个人都了解基本常识：洗手、戴口罩、不握手，以及感染症状是什么。然后，为了寻找零星病例，他们到处做发烧检查，甚至在高速公路上拦住汽车检查每个人。

一旦发现聚集性疫情，就关闭学校、影院和餐馆。只有武汉及其周边城市进入全面封锁状态。

Q: 中国人是如何重新组织起医疗响应的？

首先，他们将50%的医疗服务都转移到网上，这样人们就不用来医院看病。你有没有试过在周五晚上联络你的医生？现在你可以在网上找一个。如果你需要像胰岛素或心脏药物这样的处方药，他们可以开药并送货。

Q: 但如果你觉得自己感染了冠状病毒呢？

你会被送到发烧门诊。他们会检测你的体温、症状、病史，询问你去过哪里、与任何感染者的接触情况。他们会给你迅速扫一个CT……

Q: 等等——「给你迅速扫一个CT」？

每台机器一天大概做200次，一次扫描5到10分钟。甚至可能是部分扫描。在西方，一家医院一般每小时扫描一到两次。这和做X光不一样；病人看上去可能是正常的，但CT会显示出他们要找的「毛玻璃影」。

（艾尔沃德指的是冠状病毒患者出现的肺部异常。）

Q: 然后呢？

如果你还是疑似病人，你就会被取拭子。但很多人会被告知，「你没有患上Covid。」来这里的人有感冒的、流感的、流鼻涕的。这些都不是Covid。看看Covid的症状吧，90%有发烧、70%有干咳、30%有身体不适，呼吸困难。流鼻涕的只有4%。

Q: 拭子是用来做PCR测试的，对吧？他们做得有多快？直到前不久，我们还得把所有样本都送到亚特兰大去。

他们把时间缩短到了四个小时。

Q: 所以人们不会被送回家？

不，他们得等着。不能让人随便到处跑，传播病毒。

Q: 如果结果是阳性会怎样？

他们会被隔离。在武汉，一开始从生病到住院需要15天。他们把发现症状到隔离的时间减少到两天。这意味着受感染的人会更少——这样就能限制住病毒找到易感者的能力。

Q: 隔离和住院有什么区别？

轻症病人会去隔离中心。他们被安置在体育馆——多达1000个床位。但重症和危重病人就会直接去医院。有其他疾病或超过65岁的人也可以直接去医院。

Q: 什么是轻症、重症和危重？我们以为「轻症」就像轻微感冒那样的。

不。「轻症」是检测阳性、发烧、咳嗽——甚至可能是肺炎，但不需要吸氧。「重症」是呼吸频率上升，血氧饱和度下降，所以需要吸氧或用呼吸机。「危重」是呼吸衰竭或多器官衰竭。

Q: 所以，所谓80%的病例是轻症，并不是我们所想的那样。

我是加拿大人。这种病毒就是病毒中的韦恩·格雷茨基（Wayne Gretzky，加拿大著名冰球明星，职业生涯之初因身体条件不佳而不被看好。——译注）——人们本来觉得它不够厉害，传播速度不够快，没法产生那么大的影响。

Q: 医院也被区分开？

是的。最好的医院都用来接收重症和危重的Covid病人。所有择期手术都被推迟。病人被转移。其他医院被指定为常规医疗：还是会有女性需要分娩，还是有人在面对精神创伤和心脏病发作。

他们新建了两所医院，然后又改建了几所。如果一间病房很长，他们会在尽头建一堵带窗户的墙，所以就成了一个有「污染」和「清洁」区的隔离病房。你进去，穿上防护服，治疗病人，然后从另一头出去，脱下防护服。它就像一个伊波拉病毒治疗单元，但没有那么多的消毒，因为它不是体液传播。

Q: 重症监护的情况怎么样？

中国很擅长维持病人生命。那里的医院看上去比我在瑞士看到的一些还好。我们问：「你们有多少呼吸机？」他们说：「50台。」哇！我们问：「有多少ECMO？」他们说：「五台。」来自罗伯特·科赫研究所(Robert Koch Institute)的团队成员说：「五台？在德国，也许能有个三台。而且只有在柏林。」

（ECMO是体外膜式氧合机，在肺功能衰竭时提供血液氧合。）

Q: 谁为这一切付费？

政府明确表示：测试是免费的。如果你患了Covid-19，保险满额后，国家会承担一切费用。

美国存在速度上的障碍。人们会想：「看医生要花100美元。如果进了重症监护室要花多少钱？」这样会要你的命的。这可能会造成严重破坏。这就是全民医疗保险和安全的相关之处。美国必须好好思考这一点。

Q: 那么医疗之外的反应呢？

这种反应是全国范围的。他们有一种强烈的意识，「我们必须帮助武汉，」而不是「武汉让我们落到这种地步」。其他省份派出了4万名医疗工作者，其中许多人是自愿的。

在武汉，我们的专列在晚上进站，场面让人很是伤感——巨大的城际铁路列车呼啸而过，窗帘都是遮着的。

我们下了车，另一群人也下了车。我说：「等等，我以为只有我们可以下车。」他们穿着小夹克，拿着旗子——是一支来帮忙的广东医疗队。

Q: 武汉人如果待在家里，吃饭怎么解决？

1500万人不得不在网上订购食物。送货上门。的确是出了一些问题。但是有位女士对我说：「包裹有时候会少点东西，但是我一点也没瘦下来。」

Q: 许多政府雇员被重新安排岗位？

全社会都是这样。高速公路上的工作人员可能会测体温、递送食物或者追踪接触史。在一家医院，我遇到一个教人们怎么穿防护服的女人。我问：「你是传染病控制专家？」不，她是一名前台。这些是她学来的。

Q: 技术是怎么发挥作用的？

他们管理着大量数据，因为他们试图追踪七万个病例的所有联系人。他们关闭学校的时候，事实上只有学校大楼关闭了。学校教育转移到网上。

追踪接触史的人要填写电子表格。如果出错了就会闪黄光。是傻瓜式操作。

我们去了四川，那是个很大的地方，但相当一部分是农村。他们铺设了5G网络。我们去了省会，在一个有大屏幕的紧急中心。他们在了解一个群落的情况时遇到了问题。在同一个屏幕上，他们联系到了那个县的总部。还是没有解决问题。

于是他们派出了外勤队。这个不幸的队长在500公里以外，他的手机接到了影片电话，是省长打过去的。

Q: 社群媒体情况怎么样？

他们让微博、腾讯和微信向所有用户提供准确的信息。你们本可以让Facebook、Twitter和Instagram也这么做。

Q: 这一切在美国难道不都是不可能的吗？

你看，记者们总是说：「我们的国家可不能这样做。」人们的思维定势必须向快速反应思维转变。你打算举手投降吗？这里面存在真正的道德危险，体现的是你的易感人口对你来说意味着什么。

问问自己：你能做到那些简单的事情吗？你能隔离100个病人吗？你能追踪1000个联系人吗？如果不做，疫情会在整个小区里蔓延。

Q: 这一切之所以可能，难道不是因为中国是专制国家吗？

记者们还会说：「好吧，他们只是出于对政府的恐惧才这么做的，」就好像有个会喷火的邪恶政权在吞食婴儿似的。我也和体制外的许多人谈过——在旅馆里、火车上、夜晚的街头。

他们被动员起来，就像在战争中一样，是对病毒的恐惧驱使着他们。他们真的认为自己站在第一线，这是在保卫中国其他地区乃至整个世界。

Q: 中国现在正在重启经济。如何在不引起新一波感染的情况下做到这一点？

是「阶段性重启」。这意味着不同省份情况不同。

有些省份停课的时间会更长。有些省份只允许那些生产关乎供应链重要产品的工厂开工。至于回乡的民工——是的，成都就有500万。

首先，你要去看医生并得到一个「无风险」的证明。这个证明能用三天。

然后，你要坐火车去你工作的地方。如果是北京，那么你要先自我隔离两周。你的体温被监测，有时通过电话问询，有时通过体温检查。

Q: 临床治疗试验是如何进行的？

那些都是双盲试验，所以我不知道结果。几周后我们应该会知道更多。

最大的挑战是召集参与者。重症患者的数量在减少，已经存在竞争了。并且每个病房是由不同省份的医疗团队负责，所以你必须跟每一个团队谈，确保他们在按正确的程序走。

而且现在记录在案的试验有200项——太多了。我告诉他们：「你们得优先使用有抗病毒功效的治疗。」

Q: 而且他们在测试中药？

是的，但是是一些标准配方。并不是坐在床边现熬的草药。他们认为这些配方有一些退烧或抗炎的功效。不能抗病毒，但能让病人感觉舒服些，他们有这个习惯。

Q: 你怎么保护自己？

使用消毒洗手液。我们戴口罩，因为这是政府的政策。我们没有去见病人或者病人的密切接触者，或者进入医院的感染区。

我们还保持社交距离。我们在巴士上隔排坐。我们在自己的酒店房间吃饭，或者一人一桌。在会议室里，我们一人坐一桌并用麦克风或者提高音量说话。

这就是为什么我嗓子这么沙哑。但是我测试了，我知道我没有Covid。

Inside China’s All-Out War on the Coronavirus

Dr. Bruce Aylward, of the W.H.O., got a rare glimpse into Beijing’s campaign to stop the epidemic. Here’s what he saw.

As the leader of the World Health Organization team that visited China, Dr. Bruce Aylward feels he has been to the mountaintop — and has seen what’s possible.

During a two-week visit in early February, Dr. Aylward saw how China rapidly suppressed the coronavirus outbreak that had engulfed Wuhan, and was threatening the rest of the country.

New cases in China have dropped to about 200 a day, from more than 3,000 in early February. The numbers may rise again as China’s economy begins to revive. But for now, far more new cases are appearing elsewhere in the world.

THE LATEST Read our live coverage of the coronavirus outbreak here.

China’s counterattack can be replicated, Dr. Aylward said, but it will require speed, money, imagination and political courage.

For countries that act quickly, containment is still possible “because we don’t have a global pandemic — we have outbreaks occurring globally,” he added.

Dr. Aylward, who has 30 years experience in fighting polio, Ebola and other global health emergencies, detailed in an interview with The New York Times how he thinks the campaign against the virus should be run.

This conversation has been edited and condensed.

Q: Do we know what this virus’s lethality is? We hear some estimates that it’s close to the 1918 Spanish flu, which killed 2.5 percent of its victims, and others that it’s a little worse than the seasonal flu, which kills only 0.1 percent. How many cases are missed affects that.

There’s this big panic in the West over asymptomatic cases. Many people are asymptomatic when tested, but develop symptoms within a day or two.

In Guangdong, they went back and retested 320,000 samples originally taken for influenza surveillance and other screening. Less than 0.5 percent came up positive, which is about the same number as the 1,500 known Covid cases in the province. (Covid-19 is the medical name of the illness caused by the coronavirus.)

There is no evidence that we’re seeing only the tip of a grand iceberg, with nine-tenths of it made up of hidden zombies shedding virus. What we’re seeing is a pyramid: most of it is aboveground.

Once we can test antibodies in a bunch of people, maybe I’ll be saying, “Guess what? Those data didn’t tell us the story.” But the data we have now don’t support it.

Q: That’s good, if there’s little asymptomatic transmission. But it’s bad in that it implies that the death rates we’ve seen — from 0.7 percent in parts of China to 5.8 percent in Wuhan — are correct, right?

I’ve heard it said that “the mortality rate is not so bad because there are actually way more mild cases.” Sorry — the same number of people that were dying, still die. The real case fatality rate is probably what it is outside Hubei Province, somewhere between 1 and 2 percent.

Q: What about children? We know they are rarely hospitalized. But do they get infected? Do they infect their families?

We don’t know. That Guangdong survey also turned up almost no one under 20. Kids got flu, but not this. We have to do more studies to see if they get it and aren’t affected, and if they pass it to family members. But I asked dozens of doctors: Have you seen a chain of transmission where a child was the index case? The answer was no.

Q: Why? There’s a theory that youngsters get the four known mild coronaviruses so often that they’re protected.

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That’s still a theory. I couldn’t get enough people to agree to put it in the W.H.O. report.

Q: Does that imply that closing schools is pointless?

No. That’s still a question mark. If a disease is dangerous, and you see clusters, you have to close schools. We know that causes problems, because as soon as you send kids home, half your work force has to stay home to take care of them. But you don’t take chances with children.

Q: Are the cases in China really going down?

I know there’s suspicion, but at every testing clinic we went to, people would say, “It’s not like it was three weeks ago.” It peaked at 46,000 people asking for tests a day; when we left, it was 13,000. Hospitals had empty beds.

I didn’t see anything that suggested manipulation of numbers. A rapidly escalating outbreak has plateaued, and come down faster than would have been expected. Back of the envelope, it’s hundreds of thousands of people in China that did not get Covid-19 because of this aggressive response.

Q: Is the virus infecting almost everyone, as you would expect a novel flu to?

No — 75 to 80 percent of all clusters are in families. You get the odd ones in hospitals or restaurants or prisons, but the vast majority are in families. And only 5 to 15 percent of your close contacts develop disease. So they try to isolate you from your relatives as quickly as possible, and find everyone you had contact with in 48 hours before that.

Q: You said different cities responded differently. How?

It depended on whether they had zero cases, sporadic ones, clusters or widespread transmission.

First, you have to make sure everyone knows the basics: hand-washing, masks, not shaking hands, what the symptoms are. Then, to find sporadic cases, they do fever checks everywhere, even stopping cars on highways to check everyone.

As soon as you find clusters, you shut schools, theaters, restaurants. Only Wuhan and the cities near it went into total lockdown.

Q: How did the Chinese reorganize their medical response?

First, they moved 50 percent of all medical care online so people didn’t come in. Have you ever tried to reach your doctor on Friday night? Instead, you contacted one online. If you needed prescriptions like insulin or heart medications, they could prescribe and deliver it.

Q: But if you thought you had coronavirus?

You would be sent to a fever clinic. They would take your temperature, your symptoms, medical history, ask where you’d traveled, your contact with anyone infected. They’d whip you through a CT scan …

Q: Wait — “whip you through a CT scan”?

Each machine did maybe 200 a day. Five, 10 minutes a scan. Maybe even partial scans. A typical hospital in the West does one or two an hour. And not X-rays; they could come up normal, but a CT would show the “ground-glass opacities” they were looking for.

(Dr. Aylward was referring to lung abnormalities seen in coronavirus patients.)

Q: And then?

If you were still a suspect case, you’d get swabbed. But a lot would be told, “You’re not Covid.” People would come in with colds, flu, runny noses. That’s not Covid. If you look at the symptoms, 90 percent have fever, 70 percent have dry coughs, 30 percent have malaise, trouble breathing. Runny noses were only 4 percent.

Q: The swab was for a PCR test, right? How fast could they do that? Until recently, we were sending all of ours to Atlanta.

They got it down to four hours.

Q: So people weren’t sent home?

No, they had to wait. You don’t want someone wandering around spreading virus.

Q: If they were positive, what happened?

They’d be isolated. In Wuhan, in the beginning, it was 15 days from getting sick to hospitalization. They got it down to two days from symptoms to isolation. That meant a lot fewer infected — you choke off this thing’s ability to find susceptibles.

Q: What’s the difference between isolation and hospitalization?

With mild symptoms, you go to an isolation center. They were set up in gymnasiums, stadiums — up to 1,000 beds. But if you were severe or critical, you’d go straight to hospitals. Anyone with other illnesses or over age 65 would also go straight to hospitals.

Q: What were mild, severe and critical? We think of “mild” as like a minor cold.

No. “Mild” was a positive test, fever, cough — maybe even pneumonia, but not needing oxygen. “Severe” was breathing rate up and oxygen saturation down, so needing oxygen or a ventilator. “Critical” was respiratory failure or multi-organ failure.

So saying 80 percent of all cases are mild doesn’t mean what we thought.

I’m Canadian. This is the Wayne Gretzky of viruses — people didn’t think it was big enough or fast enough to have the impact it does.

Q: Hospitals were also separated?

Yes. The best hospitals were designated just for Covid, severe and critical. All elective surgeries were postponed. Patients were moved. Other hospitals were designated just for routine care: women still have to give birth, people still suffer trauma and heart attacks.

They built two new hospitals, and they rebuilt hospitals. If you had a long ward, they’d build a wall at the end with a window, so it was an isolation ward with “dirty” and “clean” zones. You’d go in, gown up, treat patients, and then go out the other way and de-gown. It was like an Ebola treatment unit, but without as much disinfection because it’s not body fluids.

Q: How good were the severe and critical care?

China is really good at keeping people alive. Its hospitals looked better than some I see here in Switzerland. We’d ask, “How many ventilators do you have?” They’d say “50.” Wow! We’d say, “How many ECMOs?” They’d say “five.” The team member from the Robert Koch Institute said, “Five? In Germany, you get three, maybe. And just in Berlin.”

(ECMOs are extracorporeal membrane oxygenation machines, which oxygenate the blood when the lungs fail.)

Q: Who paid for all of this?

The government made it clear: testing is free. And if it was Covid-19, when your insurance ended, the state picked up everything.

In the U.S., that’s a barrier to speed. People think: “If I see my doctor, it’s going to cost me $100. If I end up in the I.C.U., what’s it going to cost me?” That’ll kill you. That’s what could wreak havoc. This is where universal health care coverage and security intersect. The U.S. has to think this through.

Q: What about the nonmedical response?

It was nationwide. There was this tremendous sense of, “We’ve got to help Wuhan,” not “Wuhan got us into this.” Other provinces sent 40,000 medical workers, many of whom volunteered.

In Wuhan, our special train pulled in at night, and it was the saddest thing — the big intercity trains roar right through, with the blinds down.

We got off, and another group did. I said, “Hang on a minute, I thought we were the only ones allowed to get off.” They had these little jackets and a flag — it was a medical team from Guangdong coming in to help.

Q: How did people in Wuhan eat if they had to stay indoors?

Fifteen million people had to order food online. It was delivered. Yes, there were some screw-ups. But one woman said to me: “Every now and again there’s something missing from a package, but I haven’t lost any weight.”

Q: Lots of government employees were reassigned?

From all over society. A highway worker might take temperatures, deliver food or become a contact tracer. In one hospital, I met the woman teaching people how to gown up. I asked, “You’re the infection control expert?” No, she was a receptionist. She’d learned.

Q: How did technology play a role?

They’re managing massive amounts of data, because they’re trying to trace every contact of 70,000 cases. When they closed the schools, really, just the buildings closed. The schooling moved online.

Contact tracers had on-screen forms. If you made a mistake, it flashed yellow. It was idiot-proof.

We went to Sichuan, which is vast but rural. They’d rolled out 5G. We were in the capital, at an emergency center with huge screens. They had a problem understanding one cluster. On one screen, they got the county headquarters. Still didn’t solve it.

So they got the field team. Here’s this poor team leader 500 kilometers away, and he gets a video call on his phone, and it’s the governor.

Q: What about social media?

They had Weibo and Tencent and WeChat giving out accurate information to all users. You could have Facebook and Twitter and Instagram do that.

Q: Isn’t all of this impossible in America?

Look, journalists are always saying: “Well, we can’t do this in our country.” There has to be a shift in mind-set to rapid response thinking. Are you just going to throw up your hands? There’s a real moral hazard in that, a judgment call on what you think of your vulnerable populations.

Ask yourself: Can you do the easy stuff? Can you isolate 100 patients? Can you trace 1,000 contacts? If you don’t, this will roar through a community.

Q: Isn’t it possible only because China is an autocracy?

Journalists also say, “Well, they’re only acting out of fear of the government,” as if it’s some evil fire-breathing regime that eats babies. I talked to lots of people outside the system — in hotels, on trains, in the streets at night.

They’re mobilized, like in a war, and it’s fear of the virus that was driving them. They really saw themselves as on the front lines of protecting the rest of China. And the world.

Q: China is restarting its economy now. How can it do that without creating a new wave of infections?

It’s a “phased restart.” It means different things in different provinces.

Some are keeping schools closed longer. Some are only letting factories that make things crucial to the supply chain open. For migrant workers who went home — well, Chengdu has 5 million migrant workers.

First, you have to see a doctor and get a certificate that you’re “no risk.” It’s good for three days.

Then you take the train to where you work. If it’s Beijing, you then have to self-quarantine for two weeks. Your temperature is monitored, sometimes by phone, sometimes by physical check.

Q: What’s going on with the treatment clinical trials?

They’re double-blind trials, so I don’t know the results. We should know more in a couple of weeks.

The biggest challenge was enrolling people. The number of severe patients is dropping, and there’s competition for them. And every ward is run by a team from another province, so you have to negotiate with each one, make sure they’re doing the protocols right.

And there are 200 trials registered — too many. I told them: “You’ve got to prioritize things that have promising antiviral properties.”

Q: And they’re testing traditional medicines?

Yes, but it’s a few standard formulations. It’s not some guy sitting at the end of the bed cooking up herbs. They think they have some fever-reducing or anti-inflammatory properties. Not antivirals, but it makes people feel better because they’re used to it.

Q: What did you do to protect yourself?

A heap of hand-sanitizer. We wore masks, because it was government policy. We didn’t meet patients or contacts of patients or go into hospital dirty zones.

And we were socially distant. We sat one per row on the bus. We ate meals in our hotel rooms or else one person per table. In conference rooms, we sat one per table and used microphones or shouted at each other.

That’s why I’m so hoarse. But I was tested, and I know I don’t have Covid.

Donald G. McNeil Jr. is a science reporter covering epidemics and diseases of the world’s poor. He joined The Times in 1976, and has reported from 60 countries.