I find it troubling that official guidance in US is to assume protection based on vaccine receipt, regardless of antibody status (even if completely Ab negative)..
meanwhile guidance says NOT to assume anything about our protection based on being antibody positive vs negative
Personally, I'd rather be antibody positive than antibody negative.
I'm having trouble understanding why evaluating Ab responses is so frowned upon here
This reminds me a bit of the early view of rapid tests... We don't know everything, so better to just know no information.
We know that if we are vaccinated and antibody positive, it's probably better than being vaccinated and antibody negative
We know that if we haven't been vaccinated, then if we are antibody positive, we have some immunity from an infection.
Why is this so bad to know?
We could track our antibodies over time... to know if we are waning quickly or slowly.
Different people have different rates of waning.
Sure, some ppl might still be protected even if Abs become undetectable (cell mediated, etc..) but knowing how quick we wane may be crucial.
Finally, I think it's important to state that many of the issues that are coming up around antibody testing and COVID have been in existence for antibody levels for nearly all pathogens. But we don't have FDA telling people not to get their antibodies checked for those.
When rapid tests were first discussed... many ppl said "we can't use them b/c we don't know if a negative means not infectious"... no...but we could know that a positive means infectious and isolate!
We allow the edges to dictate use even when the most important uses are clear
When rapid tests were first discussed... many ppl said "we can't use them b/c we don't know if a negative means not infectious"... no...but we could know that a positive means infectious and isolate!
We allow the edges to dictate use even when the most important uses are clear
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🧵 When the goal is limiting transmission, timing of tests is everything
If you wait days for positive results before isolating, the time spent waiting must be factored in to the “effectiveness sensitivity” of a test.
Time is always ignored as a test metric. This is wrong
1/
If people are infectious for 6 days and you have to wait 2 days for results, then for every 3 positive people detected, you miss the equivalent of an entire infection Bc the sensitivity while waiting is 0%.
This means the “effective sensitivity” cannot break 67%. But worse…
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What’s particularly bad but also ignored is the **0% sensitivity** while awaiting a lab PCR result is for everyone - even people who are at absolute peak virus titers and immediate isolation is most important. For these people, rapid tests detect >95% - with immediate action
3/
When we say “pandemic of the unvaccinated”, it is stigmatizing & inaccurate - this is a pandemic of a virus that is disproportionately afflicting unvaccinated
I urge us to consider root causes of why so many are unvaccinated
🧵 When ppl give anecdotes about public health efforts not working - please proceed cautiously
It is rare that public health success makes headlines or goes viral Bc success in public health almost always represents the absence of anything interesting.
Bias is tough to spot
1/
Imagine for example if a vax failure in a single person was the only times vaccines made headlines. We’d think they didn’t work. But this is why we have trials - to ensure that we put any Vax failures into proper perspective and measure rates of success vs failure
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The same goes for anecdotes around tests, for example:
The White House Rose Garden outbreak made headlines and made everyone think that tests don’t work.
What was not discussed were the hundreds of WH events w no outbreaks owing exclusively in that WH to testing.
3/