WASHINGTON — QUESTION:
Will getting immunized with the COVID-19 vaccine cause you to test positive on a viral or antibody COVID-19 test?
Our experts say the vaccine will not cause you to test positive on viral tests, such as the PCR or rapid tests. It is possible, however, to test positive on an antibody test.
- Dr. Michael Mina- assistant professor of epidemiology at the Harvard T.H. Chan School of Public Health
- Dr. Siham Mahgoub, Medical Director for Center of Infectious Diseases Management and Research (CIDMAR) at Howard University Hospital and College of Medicine
- Centers for Disease Control and Prevention- "Myths and Facts about COVID-19 VACCINES" and "Interim Clinical Considerations for Use of COVID-19 Vaccines Currently Authorized in the United States"
First came COVID-19 tests, then came the vaccine. Now some online are asking how one affects the other.
So if you’re lucky enough to get the COVID-19 vaccine, will it cause you to test positive on a viral COVID-19 test? What about an antibody test?
Our Verify researchers spoke with Dr. Michael Mina, assistant professor of epidemiology at the Harvard T.H. Chan School of Public Health, and Dr. Siham Mahgoub, who is the medical director for Center of Infectious Diseases Management and Research (CIDMAR) at Howard University Hospital and College of Medicine. We also looked at information provided by the CDC.
Everyone concurred that the vaccine won't cause a person getting a PCR or rapid test to test positive.
"Neither the recently authorized and recommended vaccines nor the other COVID-19 vaccines currently in clinical trials in the United States can cause you to test positive on viral tests, which are used to see if you have a current infection," the CDC says online.
Dr. Mahgoub explained that the vaccine, which is given in your arm, triggers your body to create an immune response and develop antibodies, which has nothing to with viral testing that is administered to the nose.
"It does not mean that the vaccine is going to give you the actual virus in your nose, because the vaccine does not contain the actual virus,” Mahgoub said.
Dr. Mina agreed that one has nothing to do with the other: "There's really no reason for the protein mRNA to make its way up into the nose where we're sampling."
We can Verify, no, the vaccines won't make you test positive on a viral test.
Dr. Mahgoub told our researchers that she has seen people who are unknowingly sick testing positive after getting vaccinated. But that's not caused by the vaccine itself, she explained. That just means they had COVID before they got the jab.
What about antibody tests?
What about an antibody test, could the vaccine cause you to test positive?
The CDC explained, yes, it’s possible.
"If your body develops an immune response—the goal of vaccination—there is a possibility you may test positive on some antibody tests," the CDC writes online. "Antibody tests indicate you had a previous infection and that you may have some level of protection against the virus. Experts are currently looking at how COVID-19 vaccination may affect antibody testing results."
Dr. Mina says it depends on what specific molecule the antibody test you get, is looking for.
“Antibody tests very well will turn positive after somebody gets a vaccine if they're looking for antibodies against the spike protein or any of the other subunits and proteins that are in the vaccine, but they will not turn positive, if it's an antibody looking for nucleocapsid, which a lot of them are," Dr. Mina said.
Dr. Mahgoub says you shouldn't run to get an antibody test in the weeks after getting vaccinated.
"All these studies are going to come down the road so we can see how much antibodies we develop, if we need the booster, and when we're going to need the booster," she said.
The CDC agrees.
"Antibody testing is not currently recommended to assess for immunity to SARS-CoV-2 following COVID-19 vaccination because the clinical utility of post-vaccination testing has not been established," the CDC says.
For now, Mahgoub's message is to "take a deep breath, just take the vaccine and just sit tight."