
Pseudo-epidemics - Reedx
https://blog.plan99.net/pseudo-epidemics-7603b2da839
======
sevensor
I think there are a couple of shortcomings to this argument. First, it seems
to be arguing that there is no infection at all. Reports of people dying of a
new form of pneumonia would argue to the contrary, regardless of test results.
Second, it argues that the true positive rate must be so low that it's swamped
by the false positive rate. This, however, argues for an extremely high false
positive rate, given the overall positive rate we've observed. Third, the
analogy to the 2006 Dartmouth whooping cough incident is strained at best.
Almost everyone at that hospital would have been vaccinated against whooping
cough in the last ten years -- that's the P in your TDAP -- substantially
lowering the probability of epidemic. We do not, on the other hand, have a
vaccine for sars-cov-2, and yet we do have reports of people dying of
pneumonia all over the world in ways that follow consistent patterns of
infection and spread.

~~~
tom-_-
I read it a little differently. The author steers clear of debating causes of
symptoms and speculating how high or low FP% might be. He even doesn't quite
come out and say Covid-19 is a "pseudo-epidemic" though one could easily infer
that from the title + subheading.

The main points I read were:

\- A FP cannot logically be determined using two non-ground truth tests (PCR)

\- This means FP rate is unknown

\- Even if the FP rate is low (~2%), it would mean perpetual epidemic given
current testing targets

\- Public health officials and policy makers don't understand the data and/or
aren't incentivized to consider the cost of lockdowns

Though it was be nice to hear from mike_hearn himself.

~~~
mike_hearn
Yes, that's about right.

The true FP rate is probably a fair bit lower than 2%. However, even FP rates
that sound very low can still be a big problem when the signal itself is tiny.
The signal ends up dominated by FPs, which is a problem given that a positive
test is being used to trigger harsh actions, like being unable to leave your
house for two weeks.

The bigger issue is the conceptual problem. What are tests for? The ultimate
thing we care about is detecting ahead of time people who would get severe
symptoms or die, or who would be spreading the infection (assuming we take for
granted that quarantining and isolation is a reasonable policy to hold
indefinitely for such a mild disease).

The test isn't actually detecting any of these things.

