No, the World Health Organization did not say it’s safe to open stadiums to people without Covid symptoms

The debate over Texas’s plans to reopen outdoor stadiums at 50% capacity, and MLB’s apparent plans to go along with that, took an unexpected turn yesterday when a gajillion news outlets reported that World Health Organization coronavirus chief Maria Van Kerkhove had declared spread of the coronavirus that causes Covid by asymptomatic carriers to be “very rare”:

“From the data we have, it still seems to be rare that an asymptomatic person actually transmits onward to a secondary individual,” Van Kerkhove said on Monday.

“We have a number of reports from countries who are doing very detailed contact tracing. They’re following asymptomatic cases, they’re following contacts and they’re not finding secondary transmission onward. It is very rare — and much of that is not published in the literature,” she said. “We are constantly looking at this data and we’re trying to get more information from countries to truly answer this question. It still appears to be rare that an asymptomatic individual actually transmits onward.”

As a gajillion commenters both here and on Facebook immediately pointed out, if true, this would be huge news for reopening sports stadiums (and restaurants and schools and offices and everything else): Just test people for symptoms at the door, and don’t let in anyone with a fever or cough or what have you, and everyone else is good to go! If people without symptoms can’t spread Covid, we can reopen everything, all that universal social distancing was a waste!

Unfortunately, a closer read of Van Kerkhove’s comments reveals that when she says “asymptomatic,” she doesn’t actually mean “all people currently without symptoms,” even though that’s how you’d normally expect English to work. Epidemiologists divide people not currently showing symptoms into “asymptomatic” and “presymptomatic,” with the former being those who never develop symptoms, and the latter being those who will go on to develop symptoms later. And Van Kerkhove was only referring to the former, not the latter, as Harvard Global Health Institute director Ashish Jha quickly took to Twitter to clarify:

And if anyone was unclear, Van Kerkhove took to Twitter later in the day to clarify herself that she just meant it’s rare for Covid to be spread by people who never develop symptoms, not those who haven’t gotten them yet (though “clarify” is maybe an overstatement given her contorted science jargon):

So where does this leave us? If you catch the coronavirus but never develop symptoms, you’re probably pretty safe to be around even if you go about without a mask and speak with lots of P’s, K’s, and T’s — presumably because your body fought off the infection so well that you don’t have much virus in you. If you’re just still working your way up to getting sick, though — a period that typically lasts 2-14 days — then you are potentially contagious, and a hazard to others if you don’t mask up and socially distance and stay out of enclosed spaces with poor ventilation.

As Jha notes above, this is very helpful for contact tracing, since it means the government can focus all its resources on people with symptoms: Even if they were spreading virus around before they got sick, you can still find all those people after the fact. It is not helpful for screening sports fan attendance, say, because there’s no way for stadium security to tell people who will never get sick from people who haven’t gotten sick yet unless they start employing fortune tellers.

The usual caveats apply, of course, in terms of this being a developing situation and there being new scientific findings every day, etc. But as of now, there’s no reason to believe that there’s a safe way to allow mass gatherings while preventing the spread of the virus simply by temperature checks and the like. Believe me, if that changes, I will be the first to celebrate it — well, maybe after Ashish Jha.

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17 comments on “No, the World Health Organization did not say it’s safe to open stadiums to people without Covid symptoms

  1. If in 5 weeks we see no outbreak level (not spikes) in COVID19 with all the openings and demonstrations (governors and “health experts” breaking their own social distance rules) can we stop with making the word of these “health experts” sacrosanct. There is science over what we commonly understand Coronaviruses and this virus. My understanding is that extraordinary claims need extraordinary proof. If your models are not in sync with reality you need to prove your right and why people get banned from Youtube for evidence should be ignored

    1. We already have one very important data point in terms of how the virus can spread at outdoor sporting events, which is the soccer match in Milan in February that helped set off the crisis in northern Italy. What we don’t know is how much things like masks and moderate social distancing (50% capacity is way less than six feet between fans) plus temperature checks would reduce transmission in an outdoor setting. Texas reopening stadiums would certainly provide a good controlled experiment there, but by the time you found out whether it had worked or not, you’d potentially have already allowed 5-6 weeks of crazy amounts of virus to spread.

      Unless by “stop with making the word of these ‘health experts’ sacrosanct” you’re saying that you want to dispense with all scientific data in deciding how to address this pandemic, in which case I genuinely don’t know what to say to you.

      1. The Cheltenham racing festival and a rugby international are thought to have been significant contributors to England’s ‘second place’ (I’m watching you, Brazil) standing in the coronavirus sweepstakes.

        There’s actually A LOT of evidence that going back to normal is not the right thing to do unless you want exponential growth in CV19 cases again. But that is only evident if you get your health news from people who have trained in the field and spent their entire careers working in it. If you just want to listen to Fox news reporters and radio talk show hosts, I’m sure you’ll get a vastly different picture of what is safe and proper.

        Or better yet put your life in the hands of some idiot with no medical training posting his or her personal beliefs as evidence on You Tube from their basement podcast studio/office/junk storage room… and just disregard anyone with any medical training at all as being biased or corrupt.

        1. No there are models that make the assumptions you could get exponential growth assuming the inputs and data is correct. But if they create the wrong models with incorrect inputs we are well within our rights to question if the next one is correct. Expertise is not worth anything there is a big difference from what you predict and what happens. Why not listen to the cable new talking heads

          As far as the data is concerned, one of the biggest reason the lockdowns were done was because we didn’t have enough data to fully understand how to react to the virus. After 3 months we should be able to answer why certain things are ok and other things are not. If that question is not being asked because a politician is saying “we follow the sceince” and nothing else then its the culture wars pure and simple. The question isn’t is social distancing appropriate other whether people will actually do it. That comes down to credibility in leadership.

          1. The actual case and death counts have been well within the error bars of the statistical models so far.

            After three months we mostly know that lockdowns worked, because that’s all we’ve tried. How well masks work, how much social distancing is enough, how must risk there is indoors vs outdoors, etc., is still being worked out, though there are plenty of research papers out there for you to read if you’re interested.

            I linked this in the original post above, but if you missed it, it’s a pretty good rundown of what we know so far in terms of what’s riskier and what’s less risky:


          2. Matthew: We KNOW that exponential growth occurs… that’s how Italy, England and Brazil (as well as America) generated so many cases so quickly.

            It doesn’t stop being science just because you choose not to believe it.

  2. Not to go down Matthew’s path of disbelieving scientists at all, it does feel like they’re not paying attention to what’s actually happening and instead we keep getting reports about models that end up not being close to correct. For instance with asymptomatic people not being infectious, haven’t we had several stories of food processing plants in the US having nearly most of the workers at the plant test positive but asymptomatic? How is that happening? That should be a clue to something, I just know what, but it certainly implies that something is happening with asymptomatic cases:

    1. @ Ulysses……Sure, I could imagine that there could be a large number of people in a given infected group that are Asymptomatic and don’t pass along the virus.

      But, the key here is the dangerous ability of the smaller number of people who are PREsymptomatic to pass along a highly contagious virus. And, as Neil reiterated, those people DON’T KNOW that they have the virus because they are yet to get sick. They can be “healthy” for 2-14 days. But by the time they do lose their taste buds or need a ventilator, the proverbial cats are out of the bag.

      Think of the kind a damage a person can do if they roam free without a mask (or even if they have a mask and are in close contact with others in an interior space like a meat packing plant) over the course of 14 days.

      In a Catholic Mass analogy, there may be a lot of concelebrants at a Holy Day liturgy, but there is only one priest who holds the aspergillum. As he moves at a pretty good pace up and down the aisle flinging Holy Water at random he hits me square in the glasses every time.

      In this case, the Pre-symtomatic guy doesn’t know he is the priest or has a aspergillum, yet he is flinging water around everywhere, hitting my glasses and even getting some into my nose and mouth and keeps doing it until he doesn’t have the strength to show up to mass. And then, for the next 2-14 days, I turn into the priest….and on it goes.

    2. This NY Times article came out a few hours after I posted and says what I was trying to (“In the W.H.O.’s Coronavirus Stumbles, Some Scientists See a Pattern–The agency’s advice sometimes lags behind rapidly evolving research into the coronavirus, experts contend.”):

      1. WHO is not the best source for up-to-date science, that’s pretty clear. But I still don’t get what you mean about asymptomatic cases at meat packing plants — there are tons more asymptomatic cases than we at first suspected, yes, that’s been clear for a while. But that says absolutely nothing about whether asymptomatic (or presymptomatic) people can spread the virus.

        1. I found the missing part of the story that I was looking for: 46 people at the plant were symptomatic before these other tests were done which found all these asymptomatic cases. The way the stories were written I was thinking they were doing precautionary testing and found the asymptomatic cases without having any symptomatic ones first and that’s why I didn’t understand how there could be so many cases if asymptomatic people couldn’t spread it easily, if at all.

  3. Well, asymptomatic and presymptomatic are two different words and the coronavirus expert at the WHO used the former in her announcement. If the top people at that organization can’t even clearly express their pronouncements, well maybe our elected federal leader was right in wanting to cut off funding to that international bureaucracy.

    1. Last I checked, the US provides about 17% of the WHO’s funding annually. Once freed of the political interference that comes with that 17%, the WHO could (and probably will) do things America prohibits it from doing… like providing contraceptives to poor African and Asian countries so young females in third world countries don’t have 5 kids on the tarmac before they reach the age of 20.

      For every action, there is an equal and opposite… etc.

      As for Dr. Van Kerkhove, she may or may not have made a mistake in using asymptomatic instead of presymptomatic in her presentation (although it is not clear from the clarification that that is what happened… she may have said exactly what she meant).

      That does not make her less believable than the World’s Biggest Liar. If you choose to believe a sexual predator and serial fraud artist who has told more than 17,000 lies on camera in just 40 months in office instead of a medical professional then that’s on you. It’s not a very wise move IMO, given that the sexual predator in chief has also advised people to take hydroxychloroquone (some died), to put high energy UV light “inside their body” (you know where he means…), and inject bleach into their veins.

      But hey, pick whatever medical strategy you think is right for you.

      1. She meant asymptomatic, and she said asymptomatic. The problem is the popular use of that word is different from the scientific word, and she didn’t clarify that she was speaking in the narrow scientific sense.

        It wasn’t a communications masterpiece, but the media outlets that covered it also could have asked what she meant instead of just cut-and-pasting into a headline. Lots of blame to go around here.

        1. Yes, I think so too. One of the issues professionals in the science field always struggle with is getting their point across when talking to lay persons (like me, and I assume, us in general). It’s not that they aren’t trying, it’s just that it is sometimes difficult to ‘tone it down’ enough for the rest of us to understand.

          Nuclear scientists are famous for this… they generally respond to a question from the public with a pursing of the lips, followed by a pained expression that I assume means “I am not sure I can say this in a way that someone with a complete lack of knowledge on the subject – such as you have displayed – could understand”.

          I can’t necessarily feel their pain on that front, but I do understand it.

          I’m just not sure as a society how (or why) we have gotten to a place where anyone with technical qualifications in a field is considered suspect and biased. And if we are going there, then why don’t we all get our bypass operations or neurosurgeries from our unqualified cousins who work in accounting? They have no preconceived notions or biases on medical matters at all. They should be perfect for the job…

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