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Comment by Bootwizard | Hacker News Reader

Hello, Florida resident here. Our local governments and hospitals have been short on testing supplies since the beginning of the pandemic and are only allowing residents to get tests if they are showing symptoms or if you employed in healthcare (in most places). That means that most likely, the people who are getting tested will test positive. This does skew the numbers but saves our testing supplies for identifying positive cases.

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> That means that most likely, the people who are getting tested will test positive

Florida has averaged an 18% positive test rate over the last week. You can get a chart of the moving 1 week average positive rate here [1]. This was with a testing rate of 3000 tests/day per 1 million people.

Compare to 30 days ago, when they were getting a 7% positive rate on testing of 1400 tests/day per 1 million people.

Edit: might as well add deaths. 4.4 deaths/day per 1 million now (7 day average). 30 days ago it was 1.5.

[1] http://91-divoc.com/pages/covid-visualization/

For comparison here in Montana the authorities actively solicit people (by email, fb posts) with no symptoms who feel fine to come in for a test (free), in order to improve the quality of their data. They're also performing waste water testing and publishing its results.

ummm. i just called the health department in Flathead County MT and there's no free asymptomatic testing available.

Getting called up for a random sample is not the same as "Anyone who wants a test can get it" It also doesn't necessarily mean that MT has enough tests to go around

I heard that we're (as of today) seeing so many cases in Park County that surveillance testing has been suspended.

Article about surveillance testing in Montana: https://www.bozemandailychronicle.com/coronavirus/as-covid-o...

That is really interesting and on its face something that should definitely be done at random...however, its sad to say I wouldn't be at all surprised if such a system of solicitations could easily be used to manipulate the date for political purposes.

In other words if you jurisdiction has a high positive test rate, you may want to bring that % down for optics and the way to do that would be to use contact tracing (tracking tools) to solicit people who have properly been isolating and their exposure would have been minimized.

Florida reported 80k tests 7/16. 100k tests on the 12th. Not sure if they fixed the not reporting negatives yet.

Central Florida as driventhru testing, no reservation or symptoms required. They recently opened a diy swab line for people with symptoms.

https://www.wftv.com/news/local/coronavirus-where-testing-is...

Right, but aren't we (Florida) still doing worse than other states with similar testing policieS?

I've looked into how they administer the swab tests, and they are definitely are doing it wrong. At least the CDC in the Orlando NBA bubble. First they are doing a mouth swab test which will not find anything because there are no receptors in the mouth. Then they are doing a nose swab but only in the nose frontal area (Anterior nares), which is very imprecise. A proper swab test is done wide into the nostrils and swabbing the back area (nasopharyngeal - NP). The way they are doing it will find about 10% of infections, but it hurts much less than a proper NP swab.

They are also doing good pulse oximeter tests at the finger, and temperature tests, which is at least something, but only when it's too late already. PCR tests find infections 2 days earlier.

My guess is the whole CDC procedures are flawed countrywide. The written CDC guidelines favor NP over OP (mouth) over Anterior nares. International guidelines only recommend NP swabs, nothing else. Maybe they don't dare to hurt the US snowflakes with the NP swabs, so that testing is at least somewhat accepted.

Every single person I know who has gotten tested (in Michigan) has had the NP swab.

> or if you employed in healthcare

Or an NBA player.

To be fair, the league is paying for these and sending them to a private lab, so I'm not sure if they're actually coming out of the test pool available to the general public.

They also paid for the private lab to be setup. So if you really stretch it, you could come to the conclusion that they're taking testing capacity away from the public. But I think that's an unreasonable conclusion, since they created the testing capacity themselves.

There's actually a chance it added capacity.

Your state has utterly failed to ramp up testing to get to the recommended < 5% positive test rate that would have allowed contact tracing to function. Testing only symptomatic people is not in any way virtuous.

I never said it was, I simply said that is what is happening. Also are you attempting to imply that increased testing will somehow reveal a low positivity rate?

Of course the positive rate will go down as testing increases. A low positive rate means you’re detecting a significant number of the cases, which is necessary for contact tracing and isolation.

The idea that failing to get <5% positive test rate shows that a state has failed to ramp up testing is an... interesting one. It seems to have come from South Korea's goal of 5% positive tests, except their target was about decreasing the total number of cases via partial lockdown rather than increasing the number of tests. However, since that doesn't work so well for the narrative that the lockdown was the result of incompetent Republicans failing at testing, publications like the New York Times instead pushed the claim that the US needed to ramp up testing in order to reach this and catch up with South Korea. (This is almost certainly a stupid idea - trying to play catch-up with exponential growth is pretty futile, and it makes absolutely no sense to use the same target for a lagging measure of a growing epidemic as for a shrinking one. It worked great for stretching out the narrative that the US was behind South Korea in coronavirus testing well beyond the point it was actually true those.)

> it makes absolutely no sense to use the same target for a lagging measure of a growing epidemic as for a shrinking one

Indeed that measure is unattainable in a growing epidemic, but shrinking it should have been the first target. That some states are moving away from a 5% positivity target is just the symptom that those (mostly Republican) states have failed at achieving the purpose of the lockdown and are still months away from being able to implement contact tracing.

It takes about a 3-5% positive rate to ensure that you’re getting significant enough coverage to catch a large number of cases. It’s a log scale of diminishing returns below that level but above that you’re missing too many cases for isolation and contact tracing to be effective.

Are 1/3 of children showing symptoms? That's terrible.

Edit: Sorry. I misintepreted parent comment.

No, that's not the correct interpretation. 1/3 of children who are tested test positive. The children who are tested are (probably) ones who are more likely to be showing symptoms or to have been exposed. The rate of infection in the broader population of children is (probably) lower, though it's hard to say by how much without doing testing on a random sample of the population.

If they only tested children who showed symptoms, then the results mean that 30% of children showing symptoms are actually positive.

No, it means that 1/3 of children who are showing symptoms (or are otherwise recommended for a test) are in fact positive. In particular, that's 17,000 positives out of 54,000 tested.

That's far smaller than a third of the ~4 million children in Florida. Few of those are showing symptoms and thus don't get tested. At least, for another month or so, when the schools reopen and every student (and teacher) gets exposed.

No but if your a teacher or live with kids it is a scary figure.

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