'Reinfected' patient:

1. One positive RT-PCR for episode 1.
2. IgG (-) 10 days after ep 1 and just after ep 2.
3. IgG (+) 5 days after ep 2.

I don't doubt reinfections occur, but this does not constitute a proof - more likely a false positive ep 1.

1/n https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa1275/5897019

I find it deeply problematic that this was widely covered by media with conclusions drawn about what it means for COVID-19 immunity and vaccines - whether it be "vaccines are not going to work" or "this is immunity as expected". Fact is, we learn nothing from this case.

2/n

We know reinfections can occur - because nothing is ever 100% when it comes to immunology - but we (a) don't know the frequency at which it occurs, and (b) the time-dependence.

Speculating what this single (likely false) result means for COVID-19 immunity is futile.

3/n

Why do I believe this is a false positive? Because only a single positive RT-PCR was obtained for ep 1 and because we would expect binding antibodies on the Abbott NP antibody test - which is highly sensitive (reported at 100% - but again, nothing is ever 100%).

4/n

The positive IgG on day 5 after ep 2 is right on the cusp of where it could be indicative of primary infection or recall. Had it been recall, I would have expected faster seroconversion, but again, this is right at the limit, so could go either way.

5/n

Las point - even if this isn't a false positive, we still only learn one thing from this study - that reinfection is possible, which we already knew. We still don't learn about what this means for COVID-19 immunity or vaccines - we need to know frequency and time-dependence.

6/n