I am seeing a lot of people coming in for antibody testing completely asymptomatic, having never had symptoms and popping positive for the IgM on the IgM/IgG rapid tests. Talking to my coworkers and reviewing test results here I have found that none of these rapid test IgG/IgM tests had tested positive for IgG (over 100 IgM positive across our facilities) until today when I had a firefighter come in who said he felt like he and his co-corkers had been infected back in January.

The firefighter said it was so bad it caused him to quit smoking for good (still dips btw) and it was the worst his lungs have ever felt. He tested positive for both the IgM and IgG. His illness episode was around three months ago. It has made me start to wonder if the IgM hangs around for three months before IgG starts to show up. I also have high suspicion for cross reactivity with other coronavirus exposures.

What have you guys seen with these antibody tests?

That's not my point. I understand why they are coming in and I have no issue with people doing so. I am concerned with what kind of results we have been seeing and am questioning how well this test tests for Covid-19 alone and whether the IgM is useful in determining whether the patients have active disease and I came on here to see if other docs are having similar experiences and what their conclusions have been.

It seems to me that a lot of IgM positive patients have cleared the disease long ago, but we are sill having to tell them to isolate for 14 days or until our nasopharyngeal swabs come back negative. WE have been getting calls from mad business owners asking how they are supposed to operate without their entire staffs (who we have had to place in Covid isolation) and confused ones asking what these tests really mean.

Badace52 said:

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That's not my point. I understand why they are coming in and I have no issue with people doing so. I am concerned with what kind of results we have been seeing and am questioning how well this test tests for Covid-19 alone and whether the IgM is useful in determining whether the patients have active disease and I came on here to see if other docs are having similar experiences and what their conclusions have been.

It seems to me that a lot of IgM positive patients have cleared the disease long ago, but we are sill having to tell them to isolate for 14 days or until our nasopharyngeal swabs come back negative. WE have been getting calls from mad business owners asking how they are supposed to operate without their entire staffs (who we have had to place in Covid isolation) and confused ones asking what these tests really mean.

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Those businesses seem like they really care about the communities they do business in.....

Player To Be Named Later said:

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Badace52 said:

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That's not my point. I understand why they are coming in and I have no issue with people doing so. I am concerned with what kind of results we have been seeing and am questioning how well this test tests for Covid-19 alone and whether the IgM is useful in determining whether the patients have active disease and I came on here to see if other docs are having similar experiences and what their conclusions have been.

It seems to me that a lot of IgM positive patients have cleared the disease long ago, but we are sill having to tell them to isolate for 14 days or until our nasopharyngeal swabs come back negative. WE have been getting calls from mad business owners asking how they are supposed to operate without their entire staffs (who we have had to place in Covid isolation) and confused ones asking what these tests really mean.

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Those businesses seem like they really care about the communities they do business in.....

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Did you miss the part where the doc said they had already cleared the disease?

So I have been looking into this data out of China (Juanjuan Zhao Jr. et al. Antibody responses to SARS-CoV-2 in patients of novel coronavirus disease 2019. Medrxiv (pre-print). March 2019. doi: https://doi.org/10.1101/2020.03.02.20030189). It seems to suggest average time to IgM appearing is 11 days and close to 100% by 15 days while IgG appears on average by day 15 and in close to everyone by day 19 or so.

It doesn't make sense to me that all these people would be IgM positive and IgG negative. I mean we would have to be catching all of them on day 5-18 after exposure. I don't know. Maybe the tests are not as good at detecting IgG. I still have concern this test is heavily cross reacting with other seasonal coronaviruses.

Got curious and tested myself. I came back strongly IgM positive... IgG negative. I haven't had any sort of symptoms at all for over a month. I had a little episode of about a week of wheezing I attributed to seasonal allergies and my asthma about 6 weeks ago.

I was sick as a dog for five days when my whole family had the flu at the very end of January. I tested positive for flu A and so did two of my kids at that time. My wife lovingly refers to those two weeks at "the flu-pocalypse".

Our Covid nasal swabs have come back negative for every single positive IgM patient we have seen so far. Really not sure how useful these antibody tests are clinically.

plummeting to... a 1% IFR

the thing about this bug is that it's not nearly the hospitalization threat we thought it was, but it's still a stone cold killer