Has China beaten COVID-19?
Possibly the most interesting turn of events in this whole Coronavirus tragedy is the rapid reversal in fate in China.
A valid question would be; What is going on here?
The answer is, it is really hard to say. There are a number of complicating factors. The biggest being with regards to testing and reporting. There is no standardization globally for these. So, while we tend to report on global statistics, we're actually comparing Apples to Oranges to Monkeys.
The numbers in Canada aren't arrived at or reported on in the same way as the numbers from China or Italy. Yes, it is really that bad.
Put another way, the test itself isn't the same globally, which is one factor. Another is who is getting the tests and when. Countries near the beginning of the outbreak are likely testing a broad swathe of the community to get a scope of the problem. Whereas the hardest hit places are likely testing only those who are symptomatic or in critical jobs. And those recovering are back to testing a broad sampling, but the people coming in are likely a different cross section than those in the beginning.
On top of all of that China is further along than anyone else. There is no other country to compare them too at this stage.
But, given the voracity of this virus, the number of cases being reported doesn't seem plausible. Which means one a few things could be happening. Some ideas that come to mind are: the sick aren't getting tested, the numbers are being reported differently, and some level of herd immunity has taken hold.
I would say, the likeliest explanation is a combination of factors. Some of those above, plus a lot of others I haven't considered.
Firstly, perhaps out of fear, or a lack thereof more people may be choosing not to get tested now, compared to at the beginning of the outbreak. I don't know what life is like in China at the moment. But, with the initial buzz gone, it could be that people feel less concerned and are more likely to think it is something else, or that they don't need to be tested. Or, it could be that avoiding testing for a fear of being forced back into isolation.
Also, as things progress, we're getting more methodical about classifying cases. This may result in delays. Or it may result in certain results being ignored. There may also be political reasons for which the nation involved may feel the need ... alter the data.
For instance, no one seems to believe the reports coming out of Russia or North Korea. China, likewise, probably feels a need to get back to being productive and restoring/maintaining their position on the world stage. But it is hard in our global economy to justify sending people back to work if it doesn't seem safe to do so.
I'm not saying that they are lying. I'm simply suggesting it as a possibility.
And third is herd immunity.
The real problem with this disease is that we don't know truly know 2 things. The actual rate of people infected but totally asymptomatic, and the rate of people with mild enough symptoms to fly under the radar.
Honestly, I feel like this probably plays some factor. And likely a much larger factor than many are talking about at the moment.
The most reliable study we have so far is from a cruise ship. This study is reliable because a high percentage of people on board were tested. And they were confined for longer periods making symptoms harder to hide, and ignore. And this came out to a near 20% rate of people with no symptoms at all who were infected. That is a HUGE number for this sort of thing. But, the bigger problem comes when it is combined with mild cases. BTW, other reports rate asymptomatic cases between 10-30%, making that 20% all the more plausible.
Now, the mild cases. The total percentage of people in China with mild symptoms was around 80%.
Ok, this may not come as a huge surprise if you're reading the news. But, we haven't REALLY put what that means into perspective.
Basically, the mild symptoms run the gamut of symptoms not worth talking about. And mild cases may exhibit only some. Got a sore throat? That is a symptom. And many report having nothing other than that. No sore throat but a cough? There's a COVID-19 for that. No respiratory symptoms, but a fever? Still could be Coronavirus.
In short, you could be sick and have any typical seasonal illness. Or it could also be COVID-19. And, in a bid to contain the spread and restrict testing to where it is needed, people are being asked not to panic and get tested without good reason. And, people with mild symptoms are more likely to simply ignore them.
When you factor in panic, and a shortage of test capacity, I think this number of un-diagnosed cases could EASILY be orders of magnitude higher than reported cases. And, if you have people that fall in this category that aren't isolating or practising social distancing for weeks before we start really seeing cases... then it starts become quite feasible to think that in Wuhan, there may actually be MILLIONS of recovered cases which were never included in the original stats.
And, we don't have a test for recovered cases. Our count of the recovered cases at the moment is completely limited to people who were tested, and tested while positive, and who have since re-tested negative. In short, the constraints on acquiring these numbers at present is VERY limited.
Problematically however, all we can do at the moment is speculate.
Statistically speaking though, there ARE undocumented recovered cases. There is simply no confidence on what that number looks like. We have no means of identifying them, or their relative rate of occurrence.
It could be anywhere from a number so small as to make no difference, to a number as large as the bulk of the population of China.
We'll start to get some insight into this value indirectly over time.
For instance if the rate of these unknown recovered patients is high, then we'll see a more similar recovery timeline even in countries which were measures taken were light or late. And, if the number is low, the way the virus progresses even as it becomes less prevalent will be impacted much more by the measures taken.
We'll also learn a lot about this value indirectly by seeing if countries have a second wave of infection, and how quickly and hard it hits compared to the first. The population of China is a staggering near 1.4 billion. The global reported rate of infection at time of writing is just over 400k. That means that all GLOBAL cases we've reported don't make up even 1% of the population of China. And the recovered rates globally don't make up even 1/100 of a percent.
So, if our numbers are even remotely accurate, there is effectively no herd immunity in China, and a second outbreak will be just as virulent as the first.
But, if the actual spread and the actual number of recoveries is a couple of orders of magnitude higher (which given the exponential spread of this virus isn't impossible), it could actually account for a lot of the reasoning behind China's rapid recovery.
In some ways, we really need to hope we're wrong and that the total # of cases is MUCH MUCH higher.
A valid question would be; What is going on here?
The answer is, it is really hard to say. There are a number of complicating factors. The biggest being with regards to testing and reporting. There is no standardization globally for these. So, while we tend to report on global statistics, we're actually comparing Apples to Oranges to Monkeys.
The numbers in Canada aren't arrived at or reported on in the same way as the numbers from China or Italy. Yes, it is really that bad.
Put another way, the test itself isn't the same globally, which is one factor. Another is who is getting the tests and when. Countries near the beginning of the outbreak are likely testing a broad swathe of the community to get a scope of the problem. Whereas the hardest hit places are likely testing only those who are symptomatic or in critical jobs. And those recovering are back to testing a broad sampling, but the people coming in are likely a different cross section than those in the beginning.
On top of all of that China is further along than anyone else. There is no other country to compare them too at this stage.
But, given the voracity of this virus, the number of cases being reported doesn't seem plausible. Which means one a few things could be happening. Some ideas that come to mind are: the sick aren't getting tested, the numbers are being reported differently, and some level of herd immunity has taken hold.
I would say, the likeliest explanation is a combination of factors. Some of those above, plus a lot of others I haven't considered.
Firstly, perhaps out of fear, or a lack thereof more people may be choosing not to get tested now, compared to at the beginning of the outbreak. I don't know what life is like in China at the moment. But, with the initial buzz gone, it could be that people feel less concerned and are more likely to think it is something else, or that they don't need to be tested. Or, it could be that avoiding testing for a fear of being forced back into isolation.
Also, as things progress, we're getting more methodical about classifying cases. This may result in delays. Or it may result in certain results being ignored. There may also be political reasons for which the nation involved may feel the need ... alter the data.
For instance, no one seems to believe the reports coming out of Russia or North Korea. China, likewise, probably feels a need to get back to being productive and restoring/maintaining their position on the world stage. But it is hard in our global economy to justify sending people back to work if it doesn't seem safe to do so.
I'm not saying that they are lying. I'm simply suggesting it as a possibility.
And third is herd immunity.
The real problem with this disease is that we don't know truly know 2 things. The actual rate of people infected but totally asymptomatic, and the rate of people with mild enough symptoms to fly under the radar.
Honestly, I feel like this probably plays some factor. And likely a much larger factor than many are talking about at the moment.
The most reliable study we have so far is from a cruise ship. This study is reliable because a high percentage of people on board were tested. And they were confined for longer periods making symptoms harder to hide, and ignore. And this came out to a near 20% rate of people with no symptoms at all who were infected. That is a HUGE number for this sort of thing. But, the bigger problem comes when it is combined with mild cases. BTW, other reports rate asymptomatic cases between 10-30%, making that 20% all the more plausible.
Now, the mild cases. The total percentage of people in China with mild symptoms was around 80%.
Ok, this may not come as a huge surprise if you're reading the news. But, we haven't REALLY put what that means into perspective.
Basically, the mild symptoms run the gamut of symptoms not worth talking about. And mild cases may exhibit only some. Got a sore throat? That is a symptom. And many report having nothing other than that. No sore throat but a cough? There's a COVID-19 for that. No respiratory symptoms, but a fever? Still could be Coronavirus.
In short, you could be sick and have any typical seasonal illness. Or it could also be COVID-19. And, in a bid to contain the spread and restrict testing to where it is needed, people are being asked not to panic and get tested without good reason. And, people with mild symptoms are more likely to simply ignore them.
When you factor in panic, and a shortage of test capacity, I think this number of un-diagnosed cases could EASILY be orders of magnitude higher than reported cases. And, if you have people that fall in this category that aren't isolating or practising social distancing for weeks before we start really seeing cases... then it starts become quite feasible to think that in Wuhan, there may actually be MILLIONS of recovered cases which were never included in the original stats.
And, we don't have a test for recovered cases. Our count of the recovered cases at the moment is completely limited to people who were tested, and tested while positive, and who have since re-tested negative. In short, the constraints on acquiring these numbers at present is VERY limited.
Problematically however, all we can do at the moment is speculate.
Statistically speaking though, there ARE undocumented recovered cases. There is simply no confidence on what that number looks like. We have no means of identifying them, or their relative rate of occurrence.
It could be anywhere from a number so small as to make no difference, to a number as large as the bulk of the population of China.
We'll start to get some insight into this value indirectly over time.
For instance if the rate of these unknown recovered patients is high, then we'll see a more similar recovery timeline even in countries which were measures taken were light or late. And, if the number is low, the way the virus progresses even as it becomes less prevalent will be impacted much more by the measures taken.
We'll also learn a lot about this value indirectly by seeing if countries have a second wave of infection, and how quickly and hard it hits compared to the first. The population of China is a staggering near 1.4 billion. The global reported rate of infection at time of writing is just over 400k. That means that all GLOBAL cases we've reported don't make up even 1% of the population of China. And the recovered rates globally don't make up even 1/100 of a percent.
So, if our numbers are even remotely accurate, there is effectively no herd immunity in China, and a second outbreak will be just as virulent as the first.
But, if the actual spread and the actual number of recoveries is a couple of orders of magnitude higher (which given the exponential spread of this virus isn't impossible), it could actually account for a lot of the reasoning behind China's rapid recovery.
In some ways, we really need to hope we're wrong and that the total # of cases is MUCH MUCH higher.
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