antibody free testing sign

(Originally posted April 2020; updated August 2021: I have now tested positive for antibodies eight times and negative twice.)

(Original April post here; updates below) I tested positive for coronavirus (Covid-19).

I was tested via the antibody (serological) test program run by New York State on Saturday, April 25, at the Co-op City pop-up site in The Bronx. These tests use a bit of blood to check for presence of antibodies to coronavirus, which demonstrate that you have been exposed.

The state called me Thursday evening, April 30, to say that I tested positive. Several people I know who were there with me at the testing site tested negative.

What this means: Well, we don’t know. Am I immune? Not clear. Read more below.

What I  know

I had hip replacement surgery at Montefiore New Rochelle Hospital on Friday, March 13. The surgery had been scheduled since mid-February to repair bone-on-bone damage from arthritis. The surgeon is a well-known and much-praised Westchester professional.

While the idea of New Rochelle surgery in March seemed dicey, as the coronavirus spent time in the world, he and his team assured me that they have a “special wing” at the hospital — and indeed their operating suite and recovery ward are shared with a bariatric group — meaning that they are separate from the main hospital and therefore “clean.”

My house in Pelham is 2 blocks away from New Rochelle, which was an early center of the pandemic here in this area.

My grocery store, my produce store, my wine store, my dry cleaner, my gym and my (then) physical therapist are in New Rochelle. (I pretty much stopped going to most of them in early March, after the first reports of a coronavirus outbreak in New Rochelle.) The hospital is in New Rochelle, 6 blocks from my house. The Uber I took to the hospital and the Uber from were in New Rochelle. My cardiac surgical clearance was in New Rochelle.

On Monday, March 9, I did pre-op testing in New Rochelle. At New Rochelle Radiology, across from the hospital, I had a chest X-ray, a double hip X-ray and a lower extremity ultrasound to rule out clotting, required by doctors. I also crossed the street to get a blood “type and screen” test at Montefiore New Rochelle, which I had to do inside the hospital. (At this point it seemed clear that staying away from the hospital was prudent.)

After I came home that day from those two appointments, I had a few “fever rush” feelings, and also a prickly sensation in my eyes. It felt like I had been in some kind of germy soup. No temperature, though.

I went to New York City on Tuesday, March 10, to see Laurie Metcalf at the Booth Theatre on Broadway in “Who’s Afraid of Virginia Woolf?” I bought the tickets months ago. There were maybe two people in the audience wearing masks. I took the Metro North commuter train in and out, which was also probably a germy soup.

That week and the preceding week, I did a bunch of errands. Probably many in New Rochelle.

Surgery and beyond

I went in for surgery on Friday, March 13. I stayed over the weekend, and came home on Monday.

In and around the expected surgical aches and pains, one day stood out — about a week after I got home, there was a day when I felt like I had been hit by a truck — I was full of body aches and pains.

I had also some low-key upper respiratory stuff — minor drippy nose, but nothing crazy. By now, nothing. No elevated temp at all, from March 9 to now.

I was tested on April 25. I have never really felt sick, though I have been through a hip replacement (March 13) so the picture is a little hazy. I was also on ibuprofen and acetaminophen for post-op pain.

Several people asked me why I went ahead with the surgery on March 13. My hip had been yelling at me for some time, and the surgery was on the schedule and all the pre-op stuff was done. The following Wednesday, that orthopedic practice stopped surgery. The Total Hip Replacement Forum on Facebook (yes, it’s a thing) is full of people who didn’t get theirs done and are in agony.

My daughter is living with me. She says she feels pretty much OK, but had a spell a few days after mine when she felt slightly under the weather and fevery.

She did not get tested for antibodies — we have asked New York State if they will test her, because we want to help science if we are “asymptomatic carriers,” but they have pointed us toward private labs.

A test is a test, right? I mean, the answer is certain!

Not so fast. These antibody tests have a load of problems. Some of them were given emergency authorization by the F.D.A. but they are not all that clear in their results. Here’s a New York Times article about how iffy those antibody tests are. Mine was from New York State, so we want to think it’s reputable — but the science is still developing.

What about the nasal swab test for presence of infection? I didn’t have one of those (no symptoms) and those, too, are iffy in their results.

So … maybe my test was wrong.

But apparently there are a ton of asymptomatic carriers, and maybe I am (we are?) them. One study in Italy found that 43 percent of those carrying the virus had no symptoms. It is generally thought that you don’t carry the virus forever, and that antibody testing is sensitive only after you no longer have an active case.

Am I immune? Scientists don’t know for sure. With most viruses, if you have had it, you are at least resistant to that particular virus and similar ones for a time, sometimes for life. Think common colds (also caused by coronaviruses, and you can get them over and over again) vs. chickenpox or the measles (one illness means lifetime immunity). We don’t know enough about this virus to say.

“What this means, in practice, is that a positive result for coronavirus antibodies might not be a rock-solid case for being immune. Simply being positive might not be enough; people might need a certain threshold of antibodies to be protected. Again, no one knows what that level might be,” Joel Achenbach, Carolyn Y. Johnson and Paige Winfield Cunningham wrote in The Washington Post recently.

“What should, in theory, create at least some level of immunity is surviving a serious bout with the disease. A study in the wake of SARS, the similar coronavirus that triggered an epidemic in 2003, showed that survivors maintained neutralizing antibodies for two years on average, with the number of antibodies declining thereafter. Other coronaviruses in circulation in the human species also lead to at least partial immunity for some period of time.”

So the standard advice is: Keep up with your precautions — stay home, wear a mask if you must go outside, wash hands. I hope to learn more about my status as scientists learn more. Also I hope to learn more about this test’s reliability — while keeping in mind that reliability is an issue with many tests, not just this particular group of tests for coronavirus antibodies.

Why did I get tested if I wasn’t really sick?

My  village, Pelham, is right next to New Rochelle, source of the biggest New York outbreak in early March. Pelham also borders on New York City, the center of the pandemic in New York and indeed the nation and perhaps the world.

Dozens of Pelham residents have tested positive, including a number of my friends. So have hundreds of New Rochelle residents. Several residents have died — though it is not nearly as bad as in New York City, where thousands have died, including hundreds and hundreds in The Bronx.

While I live in the center of the pandemic. I have had a few symptoms — drippy nose, muscle aches and pains, but nothing serious. We have also been hearing increasingly through our reporting that people who have no symptoms can be carriers of the virus. And the idea of testing people to see how far the virus has spread (see picture above for the testing site at Co-op City in the Bronx) is a public policy issue. The testing program uses paperwork from the Wadsworth Lab that was originally designed for testing newborn babies (see pink paper).

“A survey of New Yorkers last week found that one in five city residents carried antibodies to the new coronavirus — and in that, Gov. Andrew M. Cuomo saw good news,” Apoorva Mandavilli wrote in The New York Times April 26. “If so many had been infected and survived, he reasoned, the virus may be far less deadly than previously thought. But many scientists took a darker view, seeing instead a vast pool of people who are still very vulnerable to infection. … The goal of most of these projects is to get a handle on the size and nature of the epidemic here, rather than to guide decisions about reopening the economy. But now scientists are racing to fine-tune the tests and to learn more about what having antibodies actually means, both for the patient and for the community.”

Update, May 2: Gov. Andrew Cuomo said in his daily briefing on New York’s coronavirus epidemic that the Bronx had the highest percentage of positive tests, with 27.6 percent. My testing location was in the Bronx. Here’s a screenshot of his chart.



if you’re thinking of getting a coronavirus test, we recommend doing a little homework first:

    1. Don’t ask me if you should get tested. Ask your medical professional. There are a wide range of opinions on this, and we don’t give medical advice!
    2. If you go ahead: Ask who made the test. What is the test’s methodology, and what are the results? Ask to see a package insert or written material about the test, and see if it’s approved by the FDA. (Check on this list of approved tests before you order. ) But remember what we told you above: Even if it’s approved by the FDA, that does not mean it’s been widely tested or is infallible.
    3. Ask how much it will cost. If they’re charging you, how much are they charging, and does this smell like a moneymaking scheme? I got an antibody test free under the New York State testing program, using a test developed by the Wadsworth Center, at the New York State Department of Health. It has an “emergency use authorization.” I wrote about it here.
    4. Ask about fees associated with the tests – how much are lab fees? Doctor’s fees? Make sure you’re getting all the associated costs for your test, and know that your insurance may or may not cover it.
    5. My test was administered by the New York State Department of Health; another provider might not be using an authorized test. Did you find the site on Google search or through your county or state health department? This post of ours lists a number of testing sites.
    6. Remember that in any of these tests, errors exist. So if you get a “you’re all clear” result from a nasal swab, remember that there are a lot of false negatives, and doctors say that if you have symptoms, whether you have a negative or a positive result, you should think that you’ve got it. Also, if you have a positive result in an antibody test, remember that there could easily be false positives, and doctors don’t know if positive results for presence of the antibodies means you’re immune. So don’t act as if you’re in the clear.


How I and we can help science

I am going to register at the Mount Sinai, National Institutes of Health and other programs (see below) for people who are positive and who want to donate plasma or blood to help people who may be in need of positive antibodies.

Wadsworth Lab antibody test

We do of course know that not all of the tests are reliable. But we think the New York State Wadsworth Lab test, which is what I had, has a better chance of being accurate than, say, Mens Health of Texas.

We are on lockdown here in Pelham, N.Y., in southern Westchester, and have been since pretty much the week of my hip surgery. We go to the grocery store occasionally (once every 1.5 weeks?) with mask and gloves. We also go out for walks, but we don’t hang out with anyone physically except for the cats. My daughter runs most days, at night. I did have visiting in-home physical therapy for about 2 weeks after surgery.

No one knows how long this has been circulating in our communities. So it’s worth thinking about where else we were. For example, I spoke at the Hacks/Hackers event MisinfoCon in Washington, where I traveled via Amtrak Feb. 21-22. I stayed with my brother.

First Stony Brook antibody test

But I honestly think if there was an event where I became infected, it was in that March 9-16 period.

Further details on testing: The New York State folks sent me this hotline and other information below. They also said they cannot predict when or where the next free testing site will be (like the one where I was tested). For respiratory testing, there is supposed to be no charge. See references below.

The New York State test is processed at the Wadsworth Lab, a state institution.

Update:  I went to CityMD on May 10 to get a test, wanting to confirm the results — and knowing that the various tests, both respiratory and antibody, have questionable accuracy. The CityMD test was negative for antibodies. We were told they use the Abbott test.

Update: I registered for as many plasma donation programs as I could find. The first one, at Stony Brook University, signed me up and I went to their research center for an antibody test on May 11. They told me I had antibodies, but “not enough” to donate.

Second Stony Brook antibody test

They did say that I could come back in a week, because sometimes antibodies go up and sometimes they go down. I went back in a week, and the antibody count had gone down, so they threw me out of the program. Stony Brook uses a ChemBio test. While the ChemBio test lost its emergency use authorization from the F.D.A. after my test was done, the head of the Stony Brook program told me in a phone interview that the F.D.A. had concerns about the test’s performance at the lower end — IgG values around 25 or so — but not at the level mine was (127) or the level they use for a cutoff (300). The scientist. Dr. Elliott Bennett-Guerrero, said the chances are very slim that mine is a false positive.

Update: Westchester County had a free antibody testing program at Westchester Medical Center. I went on June 24. They told me they are using the Abbott test. Mine was negative.

CityMD antibody test

The Weill-Cornell plasma donation program, in partnership with Columbia, called me back and said they are accepting donors only with confirmed positive respiratory tests. They said the researchers had asked to expand the study to people with positive antibody tests, and if they get permission, they’ll be back in touch. Then they emailed to say they had all the plasma donors they need.

Mount Sinai, Rockefeller and Northwell Health didn’t get back to me.

Update July 21: I tested positive a fourth time, this time on a rapid antibody test in a study from the Icahn School of Medicine at Mount Sinai Medical Center, “COVID in the Community: Sampling the Unsampled.” They sent out a test kit with a rapid antibody test to do at home, then two other tests — a dried blood spot test and a saliva sample — to be sent back for processing. I did the rapid antibody test, and it’s positive for IgG, the longer-lasting antibodies, but negative for IgM, the rapid-response antibodies. The other two I’ll send in and wait on results. The Mount Sinai researchers said their rapid test is a “lateral flow assay” rapid antibody test from Elabscience. It is commercially available and has an emergency use authorization from the Food and Drug Administration, they said. Details here. 

Update Aug. 24: I joined another study, this one at New York University, where a group of researchers is collecting blood samples to validate a COVID-19 antibody test they are developing. They sent me an in-home test to do. I did it and send it back, and then asked the study coordinators if they would reveal results to us. They said no, they are not allowed to do that under their IRB rules. When I signed up, they sent me an email including this message, which I must have overlooked: “This antibody test will be used only for research purposes and will not be made available to the public for antibody testing. If you provide a blood sample, you will not receive the results of the antibody test. Because this is an antibody test that we are developing and validating, the results may not be accurate.”

Update Dec. 19: I tested positive for antibodies again on the at-home rapid antibody test used in the study from Mount Sinai mentioned above. This is 9 months from what I describe above as my initial infection. I was positive for IgG antibodies on this Dec. 19 test, but not for IgM, which makes sense because IgM are the “rapid response” team while IgG hangs around longer.

In the course of our reporting about why antibody tests are so unreliable, we were trying to answer the question, “Where would you go to get a reliable one?” In talking with the study leaders at Mount Sinai, we learned that we could buy the same at-home rapid antibody tests they used, so we bought a box of 40. They are made by ElabScience, a company based in Wuhan, China.

Mount Sinai’s organizers told us they chose this test partly because it was available in quantity, and partly because “We did some internal validation at our center and also looked at the results from our COVID positive / COVID negative populations in the study. We found that the sensitivity and specificity is quite high, but again is only validated for research and not for clinical purposes.” We are using these tests to do a project here at ClearHealthCosts that we’re calling citizen science and journalism with the Covid-19 Long-Haulers Discussion Group on Facebook, sending tests to group members to see their results — and also if the results are useful for them. Read more here.

We will post about the results when they’re in: So far, it seems that a lot of people who tested positive for actual infection seem not to maintain antibodies as long as 9 months out, at least on this test.

(Update June 26, 2021:) As noted above, I have been joining as many academic studies as possible, and reporting back the results as they arrive.

On June 26, 2021, I learned that I had tested positive on the T-Detect test taken June 20 as part of a trial being run by Dr. David Lee, an emergency room doctor at New York University.

Here’s Dr. Lee’s Twitter feed. The T-Detect site says the test seeks T cells, which it says are “the first responders of the adaptive immune system and activate the antibody response. While antibodies to SARS-CoV-2 (the virus that causes COVID-19) naturally wane and are detectable in the shorter term, T cell responses can persist in the blood long after antibody responses wane.”

Lee’s theory is that autoantibody responses are part of the long Covid story, and he is collecting data by several means: Three questionnaires, by my count, as well as a blood draw. Lots of tubes of blood! Some of the tests are being done here in the United States; some of them are being sent to a lab in Germany for assessment of the autoantibody presence or absence.

My results on the T-Detect test were positive. This test is binary (yes/no) and does not deliver a relative value, say 200 as compared to others’ 600 units of whatever.

Dr. Lee wrote: “This test analyzes for evidence of a T-cell response to the SARS-CoV-2 virus. Attached you will find the report from Adaptive Biotechnologies.

“I do want to highlight that the company notes that they do not know what the test result means for patients who have already received the COVID-19 vaccination, but they are trying to figure it out. [I am indeed fully vaccinated as of March 2.]

“If you have any questions, please feel free to email me. Otherwise, the rest of the tests that we have sent for you are still being analyzed and I will contact you as soon as they are back.

“Hope things are well and thank you again for participating in our study!”

(Update June 28, 2021:) I learned today that I tested positive for antibodies again, this time in a Mount Sinai study called the “Covid Registry” study.

The results were from a May 6 antibody test in the Mount Sinai study. They said “antibody concentration” was 67, SARS COV-2 IGG level was a “strong positive.”

I asked our experts: “Isn’t this unusual? Remember, i got sick March 20, 2020, and a lot of people seem to no longer have antibodies, even people who were much sicker than I was.

“RBD COI, whatever that is, is 4.289. Receptor Binding Domain, but what is COI?

“I believe they are testing against the spike protein, not the nucleocapsid, correct? Using the Kantaro test, the one based on their Elisa test from early on?


The name of the test is on this document. So I’m pretty sure that’s what they did.

Mount Sinai created an antibody test that it liked, and that received a lot of praise in the industry. To commercialize it, Mount Sinai formed a joint venture with Biotechne under the name Kantaro. I believe from my participation in another Mount Sinai study last June or July that Mount Sinai doctors and researchers continue to use their house version for certain things, and other tests (like the one we bought from Wuhan) in other studies.

I think the Kantaro test still has an Emergency Use Authorization from the F.D.A. Also from our F.D.A. reporting: some companies, when asked for further documentation for an Emergency Use Authorization from the F.D.A., simply declined. For many reasons. Either it was too much red tape, or they realized that the F.D.A. wasn’t doing a very good job, and they had other things that were more important (commercializing via Kantaro, for example, might mean that an E.U.A. was beside the point, and they would need to get authorization under new rules or procedures).

ChemBio, maker of another test I took, did not pursue a renewed E.U.A. under the new F.D.A. rules, as far as I can see.

Abbott, maker of the two negative antibody tests I got, pursued an E.U.A. and I believe still has it. I have now tested positive for antibodies seven times, and negative two times (both negative are Abbott).

(Update Aug. 2, 2021) I tested positive for antibodies at the Mount Sinai Post-Covid Treatment Center. I visited on Monday, July 26, and got test results today. The test results are apparently on the “the
COVID-SeroKlir, Kantaro semi-quantitative SARS-CoV-2 IgG Antibody Kit,” which I am guessing is the commercialized version of the Mount Sinai test mentioned above.

It said:

“SARS CoV-2 IgG Level Moderate Positive
“Antibody Concentration 20 AU/mL

“Clinical Interpretation:

“Moderate positive (16-39 AU/mL):The
Semi-Quantitative SARS-COV-2 IgG results of 16-39
AU/mL confirm the presence of circulating IgG
antibodies specific for SARS-CoV-2 at moderate to
high levels. Corresponding serum titers range from
320 to 960.

“Note: The relationship between semi-quantitative
SARS-CoV-2 IgG(AU/mL)and Mount Sinai ELISA titer
(reciprocal of dilution) is not linear due to
methodological differences. The AU/mL unit indicates
potential equivalency for a titer in the

If you’re paying attention at home, you will note that my May 6 result said this: “The results were from a May 6 antibody test in the Mount Sinai study. They said “antibody concentration” was 67, SARS COV-2 IGG level was a “strong positive.”

And now, on a July 26 test, it’s a concentration of 20, a “moderate positive.” It seems to be the same test, judging from the results.


From the New York State folks:

Here are some avenues for plasma donation:
Potential donors:
1) Direct recruitment:
a. Several healthcare systems are running their own studies and collecting their own donor pools.
If nearby you could reach out to one of these health systems to sign up
i. Mt Sinai Medical Center:
ii. Albany Medical Center: fm
iii. Upstate Medical University – Syracuse:
iv. Stony Brook University: v. Columbia University:

2) Public donation: Individuals can also call a local Red Cross and NY Blood Center location and offer to donate.
a. American Red Cross:
b. NY Blood Center:

If you have any COVID related questions you can also call the hotline 1-888-364-3065.

Here’s a fuller list including more studies than the ones the New York State folks gave me.


Background from ClearHealthCosts:

The tests for a current viral infection are not that reliable

The antibody tests are also not that reliable, and do they confirm immunity? Not so much.

What my experience getting a test was like

How do you get an antibody test?

The New York State testing program

Jeanne Pinder

Jeanne Pinder  is the founder and CEO of ClearHealthCosts. She worked at The New York Times for almost 25 years as a reporter, editor and human resources executive, then volunteered for a buyout and founded...