6 ms·

Possible that it’s simply due to increased testing capacity. Before, many cases did not show up in the figures because there weren’t many tests carried out.

by agd 6y ago

watwut 6y ago
Are you sure testing capacity went up? I don't recall reading about that.
- tomjakubowski 6y ago
  It's definitely up since early March. It's likely that testing capacity has been the limiting factor on case count for most of this time.
- asplake 6y ago
  It’s very clear in the charts shown in the UK daily press conference. Positive tests in hospitals declining steadily, other tests (of which there has been a massive increase) making up the difference. What that says about what has actually been happening in the community is hard to say.
- chasd00 6y ago
  this is ridiculous, of course testing has gone up. https://www.google.com/amp/s/www.wsj.com/amp/articles/coronavirus-latest-news-05-09-2020-11589015996 https://www.google.com/amp/s/www.wsj.com/amp/articles/corona... pay attention to hospitalizations. that metric is disconnected from the new cases and expanded testing relationship.
  - Scipio_Afri 6y ago
    Percentage positive is disconnected from testing increases. It shows if you're catching more cases because you're testing more or if the true rate of infection is actually the same or decreasing. It still has sample bias - which depends on the availability and criteria for testing someone. As soon as hospitals start allowing elective surgeries again hospitalizations become less of an indicator and you have to go by "suspected" or "confirmed tested" covid hospitalizations.
    - dkfjdkfjda 6y ago
      I don't think it's entirely disconnected. It'd be disconnected if you had samples that are comparable (ideally random, representative of the population), but that's not the case in most countries. When you start with very limited testing capacity, you prioritize "important" groups of people that are often at higher risk of infection (healthcare workers, older people, ...) so you can expect higher percentage of people to test positive. But as you increase the capacity / number of tests, the sample structure will change - people with lower risk of infection will get tested, so it's natural to expect the percentage positive to decrease.
- orangecat 6y ago
  Daily tests have increased over the last several weeks: https://covidtracking.com/data/us-daily https://covidtracking.com/data/us-daily
  - Scipio_Afri 6y ago
    Yes but the percentage of positive tests accounts for the increase in testing rates. Positive tests divided by total tests. If percent positive of all tests is the same as before then the infection rate is not decreasing, or increasing - its constant. That is the case in many areas although some are seeing decreases or increases. E.g. some are increasing (e.g. Maine, South Dakota), some are decreasing (e.g. NYC, NJ), some are constant (e.g. DC/MD/VA have been constantly at 20% positive for the last couple of weeks now). Most states are looking for a decreasing rate of positive tests for two weeks especially of its the percent positive case is under 10%. Generally under 10% is considered under control or manageable by experts.
    - joshuamorton 6y ago
      This isn't correct. Tests aren't given randomly. They're rationed and given only to the most at risk people. As testing capacity increases, tests can be given to groups who are less likely to be infected. So at first tests were basically only given to people who had multiple symptoms, to be sure. Now you can get a test in my area if you're asymptomatic but working at a job that requires you to come into contact with other people. If the percent positive of all tests is constant even as you test more people, that means that even as you test less obviously symptomatic people, the number of infected is constant, which could mean the infection rate is going up. Or not, but it's not certain that it's complex. > Generally under 10% is considered under control or manageable by experts. Can you cite this?
      - Scipio_Afri 6y ago
        "There's no exact number to aim for, but here's a guiding principle: You want a low percentage of your tests to come back positive, around 10% or even lower, says William Hanage, an epidemiologist at Harvard." https://www.npr.org/sections/health-shots/2020/04/22/840526338/is-the-u-s-testing-enough-for-covid-19-as-debate-rages-on-heres-how-to-know https://www.npr.org/sections/health-shots/2020/04/22/8405263... There are several other sources out there that state that for example the WHO also recommended it as a guideline. Yes not everyone is being tested but the 10% does account to some degree of the "severity" of those being tested. If you're only able to test the most likely cases you'll get a much higher % positive.
- greglindahl 6y ago
  That's an interesting question, and the answer is now discussed daily in most news conferences about the pandemic. Asking interesting questions is good. Asking commonly answered questions is...
Scipio_Afri 6y ago
Testing capacity has gone up but in many places the percentage of positive cases - which accounts for the increase in testing - have stayed constant or even increased. For example in the DC/VA/MD area there has been a plateau of approximately 20% of tests positive for several weeks now which is a true indication that the infection rate is constant, not increasing or decreasing and accounts for the increased number of tests being done. NYC has definitely decreased its percentage positive in the last month, as have others, but plenty of other places in the US have seen increases or a plateau. You can find plenty of covid trackers that had the listing of total tests and total positive to determine this percent (e.g. https://covidtracking.com/data https://covidtracking.com/data ). Generally epidemiologists, infectious disease control and other experts are saying under 10% positive is considered one good indicator that the infection rate is manageable and under control. Hospital beds, like percent positive tests, are only one metric for determining health care capacity and how close we are to having an outbreak that overwhelms the all resources needed by the health care system to properly function. Globally there is a shortage of the medication used for sedating which is used when doing intubation or another medical procedure that requires sedation. Globally there is a shortage of PPE. PPE is at an extreme shortage globally still, and without PPE you have a shortage of medical workers (who then get sick or potentially spread it to other patients who aren't covid patients) - without health care workers those hospital beds become pretty useless. A lot of the initial cases in Wuhan came from cross exposure of non covid patients to covid patients at the hospital so canceling elective surgeries And mandating PPE made sense to prevent hospitals from becoming infection hotspots. Why is everyone so hyper focused on hospital beds? They also literally canceled all elective surgeries as part of these stay at home orders which freed up something like 70% of beds that were being used. Additionally there aren’t as many trauma victims because car accidents, tourism, etc is down. They know severity of cases and poor outcome when contracting the disease comes from initial viral load - being in close, confined places with someone who has it for a substantial period of time increases the severity of the disease. This is true for this virus and has mountains of evidence behind it in the study of virology to be true in general with viruses. It’s increasingly important here because the virus has no treatments in terms of medications, severe cases seem to be complex and the progression of the disease from this virus is not well understood. These guidelines and requirements for wearing a mask in public and need for health care worker PPE is a large part of the effort to help people have a less severe case of the disease if and when they do get exposed. How myopic and superficial to not think about something more than hospital beds as a metric when evaluating these shutdown policies.

Possible that it’s simply due to increased testing capacity. Before, many cases did not show up in the figures because there weren’t many tests carried out.

by agd 6y ago

Possible that it’s simply due to increased testing capacity. Before, many cases did not show up in the figures because there weren’t many tests carried out.

watwut 6y ago

Are you sure testing capacity went up? I don't recall reading about that.

tomjakubowski 6y ago
It's definitely up since early March. It's likely that testing capacity has been the limiting factor on case count for most of this time.
asplake 6y ago
It’s very clear in the charts shown in the UK daily press conference. Positive tests in hospitals declining steadily, other tests (of which there has been a massive increase) making up the difference. What that says about what has actually been happening in the community is hard to say.
chasd00 6y ago
this is ridiculous, of course testing has gone up. https://www.google.com/amp/s/www.wsj.com/amp/articles/coronavirus-latest-news-05-09-2020-11589015996 https://www.google.com/amp/s/www.wsj.com/amp/articles/corona... pay attention to hospitalizations. that metric is disconnected from the new cases and expanded testing relationship.
- Scipio_Afri 6y ago
  Percentage positive is disconnected from testing increases. It shows if you're catching more cases because you're testing more or if the true rate of infection is actually the same or decreasing. It still has sample bias - which depends on the availability and criteria for testing someone. As soon as hospitals start allowing elective surgeries again hospitalizations become less of an indicator and you have to go by "suspected" or "confirmed tested" covid hospitalizations.
  - dkfjdkfjda 6y ago
    I don't think it's entirely disconnected. It'd be disconnected if you had samples that are comparable (ideally random, representative of the population), but that's not the case in most countries. When you start with very limited testing capacity, you prioritize "important" groups of people that are often at higher risk of infection (healthcare workers, older people, ...) so you can expect higher percentage of people to test positive. But as you increase the capacity / number of tests, the sample structure will change - people with lower risk of infection will get tested, so it's natural to expect the percentage positive to decrease.
orangecat 6y ago
Daily tests have increased over the last several weeks: https://covidtracking.com/data/us-daily https://covidtracking.com/data/us-daily
- Scipio_Afri 6y ago
  Yes but the percentage of positive tests accounts for the increase in testing rates. Positive tests divided by total tests. If percent positive of all tests is the same as before then the infection rate is not decreasing, or increasing - its constant. That is the case in many areas although some are seeing decreases or increases. E.g. some are increasing (e.g. Maine, South Dakota), some are decreasing (e.g. NYC, NJ), some are constant (e.g. DC/MD/VA have been constantly at 20% positive for the last couple of weeks now). Most states are looking for a decreasing rate of positive tests for two weeks especially of its the percent positive case is under 10%. Generally under 10% is considered under control or manageable by experts.
  - joshuamorton 6y ago
    This isn't correct. Tests aren't given randomly. They're rationed and given only to the most at risk people. As testing capacity increases, tests can be given to groups who are less likely to be infected. So at first tests were basically only given to people who had multiple symptoms, to be sure. Now you can get a test in my area if you're asymptomatic but working at a job that requires you to come into contact with other people. If the percent positive of all tests is constant even as you test more people, that means that even as you test less obviously symptomatic people, the number of infected is constant, which could mean the infection rate is going up. Or not, but it's not certain that it's complex. > Generally under 10% is considered under control or manageable by experts. Can you cite this?
    - Scipio_Afri 6y ago
      "There's no exact number to aim for, but here's a guiding principle: You want a low percentage of your tests to come back positive, around 10% or even lower, says William Hanage, an epidemiologist at Harvard." https://www.npr.org/sections/health-shots/2020/04/22/840526338/is-the-u-s-testing-enough-for-covid-19-as-debate-rages-on-heres-how-to-know https://www.npr.org/sections/health-shots/2020/04/22/8405263... There are several other sources out there that state that for example the WHO also recommended it as a guideline. Yes not everyone is being tested but the 10% does account to some degree of the "severity" of those being tested. If you're only able to test the most likely cases you'll get a much higher % positive.
greglindahl 6y ago
That's an interesting question, and the answer is now discussed daily in most news conferences about the pandemic. Asking interesting questions is good. Asking commonly answered questions is...

Scipio_Afri 6y ago

Testing capacity has gone up but in many places the percentage of positive cases - which accounts for the increase in testing - have stayed constant or even increased. For example in the DC/VA/MD area there has been a plateau of approximately 20% of tests positive for several weeks now which is a true indication that the infection rate is constant, not increasing or decreasing and accounts for the increased number of tests being done. NYC has definitely decreased its percentage positive in the last month, as have others, but plenty of other places in the US have seen increases or a plateau. You can find plenty of covid trackers that had the listing of total tests and total positive to determine this percent (e.g. https://covidtracking.com/data https://covidtracking.com/data ). Generally epidemiologists, infectious disease control and other experts are saying under 10% positive is considered one good indicator that the infection rate is manageable and under control. Hospital beds, like percent positive tests, are only one metric for determining health care capacity and how close we are to having an outbreak that overwhelms the all resources needed by the health care system to properly function. Globally there is a shortage of the medication used for sedating which is used when doing intubation or another medical procedure that requires sedation. Globally there is a shortage of PPE. PPE is at an extreme shortage globally still, and without PPE you have a shortage of medical workers (who then get sick or potentially spread it to other patients who aren't covid patients) - without health care workers those hospital beds become pretty useless. A lot of the initial cases in Wuhan came from cross exposure of non covid patients to covid patients at the hospital so canceling elective surgeries And mandating PPE made sense to prevent hospitals from becoming infection hotspots. Why is everyone so hyper focused on hospital beds? They also literally canceled all elective surgeries as part of these stay at home orders which freed up something like 70% of beds that were being used. Additionally there aren’t as many trauma victims because car accidents, tourism, etc is down. They know severity of cases and poor outcome when contracting the disease comes from initial viral load - being in close, confined places with someone who has it for a substantial period of time increases the severity of the disease. This is true for this virus and has mountains of evidence behind it in the study of virology to be true in general with viruses. It’s increasingly important here because the virus has no treatments in terms of medications, severe cases seem to be complex and the progression of the disease from this virus is not well understood. These guidelines and requirements for wearing a mask in public and need for health care worker PPE is a large part of the effort to help people have a less severe case of the disease if and when they do get exposed. How myopic and superficial to not think about something more than hospital beds as a metric when evaluating these shutdown policies.