Antibody Testing Is Increasing, But A Positive Result Doesn't Prove Immunity : Shots - Health News As more and more people get tested for antibodies to the coronavirus, infectious disease specialists worry that those tested — and their employers — may not understand the limits of the results.
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Getting An Antibody Test For The Coronavirus? Here's What It Won't Tell You

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Getting An Antibody Test For The Coronavirus? Here's What It Won't Tell You

Getting An Antibody Test For The Coronavirus? Here's What It Won't Tell You

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript


As the nation tries to reopen, more and more people are getting tested to see if they have antibodies in their blood that might protect them against the coronavirus. But do those antibodies equal protection? NPR health correspondent Rob Stein has been looking into this.

ROB STEIN, BYLINE: Salvador Perez (ph) is 53 and lives in Chicago. He got really sick in April with COVID-19 - burning fever, shivering chills. I talked with Perez with one of his daughters, Sheila (ph), so she could translate for us.

SALVADOR PEREZ: (Speaking Spanish).

SHEILA: He said this has been one of his worst experience of his life. And he thought he wasn't going to make it.

STEIN: Perez isolated himself in his room in their apartment while he was sick to protect his family. But now Perez wants to go back to work at a Chinese restaurant. But the restaurant told him he needs a test, an antibody test, first. So he found one and tested positive. He has antibodies to the coronavirus, proteins that his immune system produced to fight the virus.

PEREZ: (Speaking Spanish).

SHEILA: He says he feels great that he can move back to work since we haven't really paid our bills yet. And he feels great that he could start doing what he has done before the virus again.

STEIN: But he's also nervous that he might get exposed to the virus again at the restaurant.

PEREZ: (Speaking Spanish).

SHEILA: He's anxious that he doesn't want to get sick. He's kind of scared of going back to work because he doesn't want like - or gets a little worried that he might go through it again.

STEIN: And Perez is right to be worried. Those antibodies might help protect him, but they might not or they might only protect him a little or just for a little while. No one knows. And there's lots of questions about the reliability of a lot of the antibody tests out there, but lots of people are getting the test anyway. Dr. Juanita Mora is an immunologist helping Chicago's Latino community get antibody tests.

JUANITA MORA: I had a gentleman this morning, and he came in because he wanted to do antibody testing because there had been three co-workers who had passed away from COVID-19 and there were over 200 cases of COVID-19 positive in their factory. And so prior to getting back into work, his job was requiring him to get this test done.

STEIN: But Mora says she tries to make sure all her patients understand that they still have to be careful. No one can let down their guard just because they have the antibodies.

MORA: You having positive antibodies means that you have some protection, but you can still get it again. And then you want to protect your loved ones, right? So you want to teach your kids the right thing to do. So keep the face cloth on. Keep the social distancing and so forth. Like, thank God you're able to go back to work, et cetera, but this is the only way that we can control this pandemic some.

STEIN: But people are not just getting antibody tests because they have to for work. Some employers are doing antibody testing to figure out how many employees have been exposed to the virus and where. Some labor unions are offering the test to workers to give them some sense of security. And for $119, anyone can now get one through big commercial testing companies like Quest. John Pepper and his wife Diane have been wondering whether they had COVID ever since they got sick in April, too, and whether they might now have some immunity, so they got tested.

JOHN PEPPER: I feel like we have some level of protection, that our bodies have been through this and they're fighting back and they have the capacity to fight back further if necessary. So I think it's something that's in my corner in getting through this and especially in a hot spot like New York City where we're surrounded by people who've been exposed to this and infected. And it's a bit of peace of mind for me.

STEIN: Pepper, who's 64, says they still try to stay 6 feet away from other people, wear masks when they go into stores, though mostly to put other shoppers at ease. But behind those masks, Pepper and his wife feel more relaxed, and they're thinking about having their adult children over for dinner for the first time since New York's lockdown started.

PEPPER: At some point, we have to resume life again. And based on this test, I feel like we have some sense of a bit of security.

STEIN: But all this makes many doctors and public health experts very nervous. There's a lot of misconceptions about antibody tests, like antibodies mean you aren't infected anymore - you might be. Or antibodies mean you can't catch the virus again - maybe you could. So it would be dangerous to, say, stop wearing a mask, visit your elderly parents, get too close to other people at work or anywhere else. Kelly Wroblewski is director of infectious diseases at the Association of Public Health Laboratories.

KELLY WROBLEWSKI: I think people just want this to go away and want to resume their normal lives. And I want this to go away and I want to resume my normal life. But my fear is that they were going to be used as this sort of golden ticket to demonstrate immunity when we just don't know that that's the case.

STEIN: That said, Wroblewski and others say an antibody test might offer at least some guidance if someone in the family has to go to the pharmacy or back to work. Here's Michael Mina. He's an infectious disease expert at Harvard.

MICHAEL MINA: If I had a household where I had a number of younger individuals in the household and one of whom had antibodies, I think that that individual would probably be the safest bet to be able to safely go and get the groceries. I still probably wouldn't want that person going getting groceries and then the next day going to a nursing home to see Grandma.

STEIN: So no test yet offers some kind of golden immunity passport guaranteeing it's safe to roam the world freely again. But more and more people are starting to use antibody tests to make important decisions about how to try to reemerge back into their lives.

Rob Stein, NPR News.

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