People still have antibodies from 2003 SARS infections, I don't think you've had COVID.

I was in a study. My IgG titer went up to 960, when I gave plasma twice, then 7-8 months after the infection it was below the 80 threshold to be considered positive. The weird thing was that six months in, I got tested for IgM and I was positive for that as well, which might been a sign of a second exposure. I know others in the same study who were negative a few weeks after being positive. So it might depend on the person and the test.

antibody tests are really hard. his could be a false negative. further, he could have had it, but without antibodies. or he might have had something else.

If he didn’t have antibodies then how did he ever recover? Surely the thing doesn’t just burn itself out. Without anything to fight it, won’t it just continually infect him?

There are two basic immune systems: innate and adaptive. In some cases the innate immune system clears the infection before the adaptive immune system produces detectible levels of antibodies.

https://en.wikipedia.org/wiki/Innate_immune_system?wprov=sfl...

Sorry, I'm aware of that in general. I was wondering in this case. I suppose that's possible for people who don't fall sick (I assume that's why low viral load means you can get exposed and not get sick?) but OP was quite sick.

I think it’s unlikely that’s it for someone seriously ill for an extended period.

some people are recovering through other responses, including t-cell response, etc. I don't have the academic experience, the clinic experience, or his specific medical history, so I can't speak specifically. I do recall lots of papers at the beginning of Covid talking about high t-cell responses in patients without a lingering anti-body response. That all could have been early science based on poor data as well though.

Based on the information provided it seems highly unlikely the OP had covid.

It isn't impossible but the lack of antibodies is just one further data point. Most people who recover have positive antibody tests.

>antibody tests are really hard.

Are you referring to the quantitative side? You can simply buy the antibody standard and sVNT test kit from Genscript. You can get a 96 test kit for under $3k. We have it and it works quite well.

the general concept of antibody tests. Antibodies have serious dilution. Detection is a challenging problem. Many antibody tests (ex. measles) has a pretty high (in my unqualified opinion) false negative rate. Its a tough problem to solve in general.

a single paper discussing false reports - https://pubmed.ncbi.nlm.nih.gov/14574997/

Well, let me first state the obvious - no test anywhere is perfect. But when it comes to antibody tests you have to be a bit more specific and discuss the underlying technology and method of detection. For e.g. there are 1129 diagnostic products for covid, and not all of them are identical. There are many reasons for false-negatives and some could be specific to the product being used. The paper you linked to is not about COVID19, its from 2003 and also its scope is not a general review of antibody tests. Its an investigation into false-positives with a specific underlying autoimmune disease possibly masking the result. I am not familiar with this study to speak in any great detail.

https://www.finddx.org/covid-19/pipeline/

> I have been supplementing vitamin D and zinc since March '20, but I'm not sure that would have prevented antibody formation if I was infected.

First, there's no scientific basis for doing so. Unless your diet is deficient of zinc or you're spending months in an overcast winter environment neither is going to do anything for you. They certainly won't have any impact on antibody formation.

42% of the US population has a vitamin D deficiency [0]. In the HN population, that number might even be higher (extrapolating my experience with tech workers and the hours they spend outside).

I would encourage most people here to have their Vitamin D levels checked and take supplements, especially in the winter months.

[0] https://pubmed.ncbi.nlm.nih.gov/21310306/

Most doctors I’ve met agreed with this.

Also certain diets could have other deficiencies, like in my case I almost never eat fish so I add omega3 (DHA).

I agree, if it's likely your deficient you should get tested and supplement as necessary. That's my point. It should be done as part of evidence based medicine and not a random thing you decide to do with no supporting evidence.

Ideally everyone should get periodic vitamin D level tests, and then adjust their diet, sun exposure, and supplementation accordingly. But unfortunately it's just not practical to test everyone. And also we know that a large fraction of the population is deficient, and that moderate supplement doses are generally safe. So routine supplementation is justified for most of us on an evidence based medicine basis.

There is some limited in vitro evidence for zinc as a treatment.

https://journals.plos.org/plospathogens/article?id=10.1371/j...

The evidence for vitamin D is much stronger including multiple randomized controlled trials.

https://vitamin-d-covid.shotwell.ca/

I have seen scientific evidence that Vit D supplimenting helps. In Spain its prescribed if you get covid. re: "unless you are deficient": you supliment to ensure you arent deficient, you are foolish to risk zinc or Vit D deficiency if you know you have covid. If you plan a fews days in bed you are (usually) not going to get much sun. It's foolish to risk deficiency of any vitamin while ill.

> First, there's no scientific basis for doing so.

"No scientific basis" doesn't necessarily mean "false", otherwise you create a world where everything not mandatory is forbidden. Many doctors do exist in this world; they're always totally confident even when they're wrong, and they will tell you to not do things unless it's the specific thing they want you to do.

"No scientific basis" means you look at the best scientific evidence we have today and make informed decisions based on it. You don't make stuff up with the hope that it's helpful.

>you're spending months in an overcast winter environment

I'd imagine this would include ~30-40% of Americans.

“ there's no scientific basis”

Theres no scientific basis for anything until a proper study is done. Doesn't mean it isn't true. And consider that estimates are as high as 50% of scientific papers’ results are false (especially in bio).

N.B.1: I'm a scientist in a government lab

N.B. 2: I’m not impugning science, just fellow scientists.

What's your point? When you make a medical decision it should be based on the best research done to date. Just because existing research doesn't mean something isn't true isn't a reason to do it.

> And consider that estimates are as high as 50% of scientific papers’ results are false (especially in bio).

Source?

Ioannidis JPA (2005) Why Most Published Research Findings Are False. PLoS Med 2(8): e124. https://doi.org/10.1371/journal.pmed.0020124

Where is the 50% number? Or are you linking to a random paper? (i.e. not the source for the claim)

Did you even read the paper? "Most" is >50%.

Nope. You don't invent numbers like that. A claim that includes a specific number needs an actual citation which includes the number.

"Most Research Findings Are False for Most Research Designs and for Most Fields" is a ridiculous claim. I don't know a single scientist who believes that. How many scientists have you spoken to in the bio field?

Do you have a substantiave criticism of the paper that I linked?

I’m actually surprised that I don’t hear more “I thought I had COVID in 2019, took an antibody test, and was right” anecdotes. Especially if the false positive rate on these tests is significant.

The antibody tests do occasionally come up negative for patients who had confirmed infections. You might want to get the Adaptive Biotechnologies T-Detect COVID test which assays memory T cells.

https://www.fda.gov/news-events/press-announcements/coronavi...