When I last checked the Covid-19 trend line, it showed an encouraging flattening in the rate of growth of new cases in the US. China and South Korea had brought things under control much earlier and it looks like Hong Kong and Australia are also doing well. France, Italy, and Germany are definitely showing signs that they have passed the peak and slowing down the rate of growth.
But one of the concerns with the US data is that due to the massive incompetence of the Trump administration in rolling out testing and collecting data, testing is nowhere near a widespread as it should be.
From the beginning of the coronavirus crisis, lapses by the federal government have compromised efforts to detect the pathogen in patients and communities. A diagnostic test developed by the Centers for Disease Control and Prevention proved to be flawed. The F.D.A. failed to speed approval for commercial labs to make tests widely available. All of that means that the U.S. has been far behind in combating the virus.
Nationally, an average of 145,000 people have been tested for the virus each day over the past week, according to the Covid Tracking Project, which reported a total of nearly 3.1 million tests across the United States as of Tuesday night.
State health officials and medical providers around the country say they are unable to test as many people as they would like. Many of them say the biggest challenge is getting not the diagnostic tests themselves but the supplies to process them, including chemical reagents, swabs and pipettes. Manufacturers are facing a huge global demand as every country fights the pandemic, with many attempting the widest-scale testing they have ever undertaken.
So less that 1% of the country has been tested so far. It seems like one has to display symptoms of the disease to get tested, unless you are a wealthy person and/or a celebrity who seem to be able to get tested even in the absence of symptoms. This means that asymptomatic carriers of the virus are not showing up in the data, leading to undercounting.
Furthermore hospitals in the US are reporting that some patients are testing negative when their symptoms seem to clearly point to them having the disease, exacerbating the undercounting problem.
Tests turning up negative even when all signs point to COVID-19 has been a common experience in American hospitals over the past month, public health experts have told ProPublica. It’s unclear what proportion of these negative results are inaccurate — known as “false negatives” — and whether that’s due to some external factor, like bad sample collection, or because of an issue inherent in the tests’ design.
Neither the major test manufacturers, the U.S. Food and Drug Administration or the U.S. Centers for Disease Control and Prevention would say how common false negatives are. While the FDA requires test-makers to report any known instances of false negatives as a condition of granting them provisional approval, known as emergency use authorizations, no such reports are visible in a database the agency maintains for that purpose.
Nearly all tests have some degree of false negatives and false positives but in cases like this the former is more significant in terms of public health, because one wants to limit the number of carriers wandering around in public, unknowingly infecting others. Not knowing the rate of false negatives is concerning.
When the country starts to loosen its restrictions, it may be the case that you might need a certificate that you have tested negative to be able to go to your workplace, so that your co-workers feel comfortable around you. But if the tests have a high false negative rate, that might lead to a false sense of reassurance.
What happened to those tests that returned results “instantly” according to Cheato? Thought those were rolling out last week or two ago. Surely he wasn’t lying to us!
I think he’s deliberately getting in the way of testing to make sure the numbers still reflect the reality he wants. He’s already told us out loud that’s his goal.
I have no idea about the situation in the rest of the country, but at the hospital where the Partner works, they have 4 machines sitting idle because they do not have the reagent to run the tests. The machines can return results in 10 minutes. In the meantime doctors are forced to use a test that takes days to get back results. I am not really sure where the fault lies in the hospital not being able to get the reagent. I would not be surprised if it’s petty vindictiveness on the part of some politician.
As far as asymptomatic people they are sure out there. One was a doctor and in order to go to work at the hospital he had to be tested. Turned out he was positive and so was his whole family -- but yet they are showing no symptoms at all.
There are a lot of them.
Fauci estimates that 25-50% of all cases are asymptomatic.
On the Theodore Roosevelt aircraft carrier, out of 600 positives, the majority were asymptomatic. Some of those will go on to become symptomatic, but most of them probably won’t.
This is a problem we will be dealing with for at least the next few years.
Have a friend who tested negative. she can’t seem to shake it after 4 weeks, so she is looking at getting retested.
I’ve a close friend working in the Nightingale Hospital in London (the one that’s been thrown together in an exhibition space in a couple of weeks and staffed with volunteers from other parts of the NHS). She’s done a LOT of testing recently. She was assisting a doctor administering a COVID19 test to a patient, and offered to fetch her a vomit bucket. The doctor asked why she might need such a thing. My friend observed (to me, later, rather than to the doctor at the time) that if that doctor didn’t think a vomit bucket necessary (and didn’t know why she might need one) she didn’t know how to administer the test properly. One is forced to wonder how many other tests have been administered by doctors who’ve not been properly trained. There’s a source of plenty of false negatives right there.
Rob Grigjanis says
He can’t escape the reality represented by the number of deaths.
Rob Grigjanis @ #6:
From the nonsense Trump utters, I suspect his ‘reality’ is from a parallel dimension that only rarely and randomly overlaps with the universe you and I live in.
But I don’t watch Faux News, Breitbart, etc.
Heidi Nemeth says
“When the country starts to loosen its restrictions, it may be the case that you might need a certificate that you have tested negative to be able to go to your workplace, so that your co-workers feel comfortable around you. But if the tests have a high false negative rate, that might lead to a false sense of reassurance.”
Assuming people who have recuperated from the virus have temporary immunity from getting the virus again, the antibody titer tests showing you have had the virus will be what gets you a back-to-work (get out of jail free!) card. On the other hand, not having had the virus means you are still susceptible, might become infected, be a carrier while still asymptomatic, and still test negative. Yes, it’s a false negative, but an expected false negative. A person with no immunity offers no security to their coworkers against the disease.
Heidi Nemeth says
@6 He can’t escape the reality represented by the number of deaths.
The number of deaths is a rather squishy number. Remember in Hurricane Maria, there were something like 64 official deaths in Puerto Rico due to the hurricane? Trump said the number of deaths was very small. Meanwhile, people on the island recounted knowing many people who had died and seeing many coffins. There was no electricity, few means of communication, a lack of knowledge of anything beyond the immediate surroundings for months. It wasn’t until a study was done more than a year later of the excess number of deaths during the hurricane and for the six months afterward that it became clear epidemiologically that the hurricane cause more than 3000 deaths.
We know the number of Covid-19 deaths as the number of people with positive test results who have died. If people weren’t tested before death, their deaths were not ascribed to Covid-19. People who died at home, in nursing homes, or places other than the hospital have not been included in the death count. This week Ohio (and other states, because they have to report it now to the CDC) just started counting the “presumed deaths” due to Covid-19. Presumed deaths are those with known exposure and severe symptoms of corona virus but who were not tested before death.
Because testing has lagged infection, the true number of coronavirus deaths will only be known after this pandemic is over and studies can be done comparing the number of deaths during the pandemic with the average number of deaths in recent years.
Rob Grigjanis says
@10: Can’t get much more squishy than number of cases. It depends on availability of test kits, and local testing protocols. Those can vary greatly between jurisdictions, and within jurisdictions over time.
Number of confirmed deaths is at least a pretty solid lower bound.