Now that tens of millions of Americans are vaccinated against the coronavirus, many are wondering: Do I have enough antibodies to keep me safe?
For a vast majority of people, the answer is yes. That hasn’t stopped hordes from stampeding to the local doc-in-a-box for antibody testing. But to get a reliable answer from testing, vaccinated people have to get a specific kind of test, and at the right time.
Take the test too soon, or rely on one that looks for the wrong antibodies — all too easy to do, given the befuddling array of tests now available — and you may believe yourself to still be vulnerable when you are not.
Actually, scientists would prefer that the average vaccinated person not get antibody testing at all, on the grounds that it’s unnecessary. In clinical trials, the vaccines authorized in the United States provoked a strong antibody response in virtually all of the participants.
But antibody tests can be crucial for people with weak immune systems or those who take certain medications — a broad category encompassing millions of people who are recipients of organ donations, have certain blood cancers, or who take steroids or other drugs that suppress the immune system. Mounting evidence suggests that a significant proportion of these people do not produce a sufficient antibody response after vaccination.