One of my neighbors asked me this question 2 days ago, I saw it come up in comments under news articles, and I just now saw it again online as well.
His question, which I've actually heard a few times now, is a good one: "Can the antibody test differentiate between active antibodies of current infection vs. prior infection?"
The short answer is yes - although these are the first tests (not necessarily the best yet), as well as there is an overlap of time between the appearance of active antibodies (IgM) and total immunity antibodies (IgG) which isn't well understood yet.
See more on the specifics of how they can tell/differentiate between antibodies below.
Aside: Yes, my neighbor and I practiced social distancing. He's a high-school basketball coach for a private school and personal trainer on the side, with shared custody of 3 boys.
Since the schools are out, and he works for a private school, he is now just personal-training to make a living, still with equipment, but one person at a time, outside, staying 6 feet apart, but not wearing his gloves as he had been until that day.
So I brought him - and the person he was training - a pair of mine (while I wore mine) because as I told him, he was worrying me to death, out there, using shared equipment without gloves on lol - turns out he had run out of gloves and thus the reason he wasn't wearing any now, but still trying to work.
To which my husband replied to my doing with ...
Mark: "Will you please stop giving all our gloves away? lol. I'm going go in here to get some and find they're aren't any left because you gave them to everybody else. I love you for it, but remember to save some? :)"
Me: Ohh, all right lol. But I really haven't given them all away, plus more are on the way, because I ordered them three weeks ago when I found out they became back-ordered after the first 300 I purchased, they are supposed to be here Monday:)
Mark: "Do you think any of these people would do the same for you? I think some of them have already proven they wouldn't."
"Track record, Chrystal - I can count 2 people I've personally watched you give everything you had away to, who even bothered to remember it, who didn't sh*t on you later - especially if they start taking too much and you draw a line in the sand about it. And I know there were even more before I was around. In fact, I know 2 people who've gone on record as saying they'd destroy your life, even kill you, if they had the chance, because you knew too much."
"Yet you'd still keep help them all anyway. Isn't that the definition of insanity? Keep doing something the same way but expecting different results and to your own detriment? lol ;)"
Me: "Lol, probably - but not the point! :) And I'm getting better about drawing those boundaries, sooner. I think. I'm not letting those people you're referring to back into my life, mind you, but we're in a public health crisis and I'm doing my part to stop the spread of the virus, as well as propaganda about the virus - because this is the most dangerous thing we've faced in a very long time."
"I'm not doing this to get anything back. This is not about how I can benefit, like some sort of transaction. This is about if we want this world to be a better place and for people to treat each other better, then we have to exemplify that, despite what other people do and say."
"How they respond to the gift isn't the point. The point is, they are in need, whether they realize it and admit it or not. So I lay out the solution, then say 'Here it is, take it or leave it'."
"Yes, sometimes gifts go untrusted because often other people give them with unseen obligation strings (and I get that/have seen that myself), or they're seen as an intrusion or insult, or go unappreciated. ( I usually don't offer unless its becomes my business, it becomes public business, or they've shared private need with me - otherwise, they'd be correct, it would be an intrusion)."
"Yes, sometimes people will forget, or make excuses not to reciprocate when it's your turn, finding excuses/blame you for being in the situation instead."
"Yes, sometimes they'll ascribe the worst motivations they can think of for your gift, even project onto you their own motivations."
"So what? AND? Lol, like any of those are new to me, I've gotten used to it. In fact, it's a pleasant surprise when people do."
"And you forgot the people who helped ME without expecting anything in return/didn't obligate ME, by the way (naming 4 people). Yes, it's a smaller number, but still, there are good people left in the world."
"We don't do it for a thank you or to get something in return, we do it because it's the right thing to do. Because it's what Christ did. And he was a lot better at it than me, and was treated much worse than me. I'm not responsible for what other people do, just me. So the rest is on their souls, not mine. lol"ANYway lol ...
... back to my neighbor, he already been really sick a few weeks ago from what they thought was a "new strain of flu" - but now we're wondering if he actually had COVID-19 and we just didn't have the testing available yet, and thus the reason for his question.
*Remember, I'm no doctor* - I just transcribe what they say (for 24 years, minus during the recession), verifying the terms I'm hearing it with reputable medical-journal information or information from the clinicians themselves.
And don't forget to keep in mind, doctors are human and make mistakes/can be wrong, just like everyone else - including and especially me lol
My nighttime gig is transcribing for a major Canadian academic/university hospital and outpatient clinic - including both the Allergy and Immunology and Infectious Disease Departments.
I could give you the scholarly articles and medical journal links I use for my research, but the links below are a bit more succinct; they're essentially the quick "cheat-sheet" versions.
Here's my written-version reply to this question online ...
(Forgive any typos - it's been an especially long week, to include Snuggy Pug's passing/little sleep, it's my only day off, and it's still early/no caffeine yet lol):
As I understand it, theoretically, they test for the presence of two different types of antibodies, IgM and IgG.
The presence of IgM, which develops a few days after infection, means you are likely currently fighting infection. The presence of IgG, which show up approximately 10-14 days later, indicate true immunity.
Thus, it's assumed if you have the presence of IgG and are asymptomatic, you've beaten it/are now immune.
However, these are approximations and not absolutes, as we still aren't 100% sure when it comes to SARS-CoV2, which is breaking all prior pattern rules - but to be fair, they did say they're the first tests, not best ;)
For example, there appears to a bit of overlap between the presence of the both types they're not sure about, which could mean you're still infectious.
What we're counting on instead is what we do know - how our bodies respond to infection - or at least we're in the ballpark range of certainty on that :)
Here's just a quick, cheat-sheet sort description of the different types of immunoglobulins ...
Here's a link to the two types of tests in the U.S. ...
Just an FYI, many - Kentucky hospitals being no exception - are trying plasma transfusions to help boost/push along this immunity process - and although patients are improving, they're not sure if it's the plasma or the patients just got better.
Hope this helps. Remember, I'm no doctor, I just type for them :)
After another commenter replied, saying he thinks people are getting the tests for presence of/antibodies to confused, I agreed, writing this follow-up:
Sorry, retrying this comment because of a typo and an important addition (I type fast and go)-
Yes, two different tests, - one for presence of, the other for body immunologic response to - and I agree, people are getting them confused - and there are more types in the works to make things even more confusing :)
Again, I'm not doctor, I just type what comes out of their mouths lol - but if I understand correctly, the tests we already had were just testing for presence of the virus in mucosal linings - not immunologic response to the virus.
At present, they're just a swab, looking for the presence of the antigen itself, its viral RNA (although there are some rapid finger-prick blood tests apparently in the works).
The antibodies/immunologic tests are usually blood tests, focused on our bodies' immunologic response to the virus, our antibodies TO the antigen, the viral RNA.
Here's a site that explains it better than I am doing lol:
But yes, you are are correct - two different tests and people are confused.
The new tests are blood and therefore better determinants of the presence of both the virus and the antibodies to the virus (and that's why everyone's excited about it :)
IMO, focusing on how to reproduce immunologic response in others is our quickest, best shot.
Because we currently don't have any "cures" for viruses except hepatitis C. We have some anti-virals to reduce the viral load (HIV), but no cures except for hepatitis C (that I know of).
(Antibiotics, of course, are useless against viruses unless secondary bacterial infections develop.)
PS - Since I wrote that, of course the right-wing-extremist conspiracy theorists arrived, in full force, talking about not knowing anyone personally with it and spreading wild speculative tabloid/Twitter opinion from internet nobodies they don't even know, about the government and Bill Gates being responsible.
First of all, unless you live in densely-populated city that's a known hotspot, where people are packed in like sardines - like NYC, Seattle, or LA in the United States - most people don't know anyone with it personally, at its current proportions.
Hellllooooo - is this thing on?
That's precisely what we're trying to avoid happening with all of these social restrictions!
However, I have transcribed reports on a couple of patients with the mild phenotype, my husband's work knows which student tested positive last week, and most importantly, my sister-in-law lives in a suburb of New York City and has had several friends who had it and are now recovered.
Also, I already mentioned neither the government nor Bill Gates would profit by creating a virus or a hoax - although Bill Gates may see opportunity, in this extra attention - of course he would, he's a master marketer and any attention is good attention and an opportunity to market, right?
However, right-wing extremists (though not exclusive to right-wing extremists) often confuse the order of events, using even self-defense as proof of both guilt and that their accusations/actions were justified, instead of realizing they actually created self-fulfilling prophecy by being relentlessly aggressive a-holes lol.
Thus, I'm not going to further respond - because you can't present logic to people that irrational/paranoid - don't even try, trust me (I have a few times, particularly when Trump was elected, and normally rational people went cuckoo and started supporting outlandish conspiracies without proof.)
In real life, after trying previously and getting nowhere, I now either change the subject, or I've even been known to just walk away if they push.
Because they're trying to convince you, not listen to you.
And you can't present logic/reason/fact to people who believe this kind of stuff, they just find a way around it and continue to go down the rabbit hole/up their own arse anyway, so there' s no point lol.
They have the right to say and believe what they want - and I have the right to walk away, no longer participate, or even give the appearance of entertaining/enabling that level of pure, unadulterated insanity lol.
Again - the only reason I was at that site full of whackadoodles today was to answer a reasonable question from one of the three more rational commenters who still comment there, which was residual from our discussion the day prior.
And the reason I initially commented then - which is extremely rare - is exactly what I said below: I'm trying to help combat not only the spread of the virus, but the spread of dysinformation/propaganda about the virus.
What I was NOT there to do is combat the sort of people who are hell-bent on believing everything they read in tabloids, Twitter, or their own imagination -- to include things like we Democrats are all led by a race of shape-shifting reptilians who comprise the Illuminati/New World Order and run a Satanic pedophile ring, which includes the Clintons, Bill Gates, Warren Buffet, George Soros, the Queen, the Rothschilds, and everyone else who's a billionaire (except the billionaires they voted for, of course;) -- because they refuse to trust anything they read in the regular media because other right-wingers told them not to.
Sorry to disappoint lol.
The media may not get always it right, it may be politically slanted at times - but at least I know who's writing it and their qualifications VS. a 15-year-old bipolar hacker, off his meds and hiding in his mom's basement, pretending to be God only knows who, with 20 different IDs lol.
I'm sometimes tempted to ask them what could do if any of these conspiracies were true (or even made sense)?
I suspect the answer would be nothing.
We'd say, "Wow, that sucks. Oh well" - and that would be the extent of it lol.
Because there's nothing we could do, anyway.
Aaannnnd we're back to my point - thank you for agreeing with me that following social restriction guidelines set forth by public health agencies/governments is the best course of action lol ;)