Sure Signs You Have COVID Antibodies

If you have been infected with the virus that causes COVID-19, one of the ways your immune system responds is by producing protective antibodies. "We don't know how long the immune system will protect against reinfection or protect against variants," says the Cleveland Clinic. "We still recommend those eligible receive the vaccine… It is safe to get the COVID-19 vaccine even if you have previously tested positive for COVID-19." So how do you know if you have antibodies? Here are five signs you have COVID-19 antibodies, according to experts. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.

Research shows that COVID-19 symptoms are strongly linked to antibodies. "Looking more closely at the data, we saw that people who had a greater number of symptoms while they were ill with COVID – particularly the 'classic three' symptoms of cough, fever and loss of smell (anosmia) – were more likely to have gained antibodies against the virus," according to research from the ZOE COVID-19 Study.

"Antibodies begin mobilizing within the first few days following an infection with COVID-19 or after receiving the vaccine," say Prakash Nagarkatti and Mitzi Nagarkatti, both professors of pathology, microbiology and immunology at the University of South Carolina. "They steadily increase in concentration for weeks and months thereafter. So by three months following infection, people have a robust antibody response. This is why the Centers for Disease Control and Prevention has long held that people who have had a confirmed COVID-19 infection in the past 90 days do not need to quarantine when they come into contact with someone with COVID-19. But by about six months, antibodies start declining. This is what led to the so-called 'waning immunity' that researchers observed in the fall of 2021, months after many people had been fully vaccinated."

If you've previously had COVID-19 and are vaccinated against the virus, you have what is called "hybrid immunity." "Hybrid immunity is really the most robust correlate of protection against severe disease and death," says Galit Alter, Ph.D, professor of medicine at Harvard Medical School. "Even folks who've gotten two shots … don't seem to do as well at resisting COVID-19 as folks who had hybrid immunity due to infection either before or after vaccination. There is something special about seeing the virus in its entirety."

According to the CDC, 60% of Americans have COVID-19 antibodies—but that doesn't mean they are safe from the virus. "We know that is not what this means. Reinfection happens," says Dr. Kristie Clarke, co-lead for the CDC's COVID-19 Epidemiology and Surveillance Taskforce Seroprevalence Team. "Protection from vaccination and protection from previous infections does wane over time." A test can tell you if you have antibodies. "Antibody tests for COVID-19 are available through healthcare professionals and laboratories. Check with your healthcare professional to see if they offer antibody tests and whether you should get one. Antibody tests should generally not be used to diagnose a current infection with the virus that causes COVID-19. An antibody test may not show if you have a current infection because it can take 1 to 3 weeks after the infection for your body to make antibodies," says the CDC.

Research shows that people who smoke and are in poor health are less likely to have antibodies after infection. "It's interesting to observe that, unlike vaccination, it's not just older, frailer or overweight adults who gain least protection from a previous infection, but rather anyone with poorer overall health and those who smoke," says Tim Spector, lead scientist on the ZOE COVID Study. "Our data show that the best way to protect yourself and others from COVID-19, even if you have had the virus previously, is to have 2 doses of vaccine and the booster when offered, and to take sensible precautions such as wearing a mask. Not only does this cut your chances of catching the virus and becoming seriously ill, it also reduces the likelihood of passing it on to others who may be more vulnerable." 

Do not think you are bulletproof if you have antibodies. Follow the public health fundamentals and help end this pandemic, no matter where you live—get vaccinated or boosted ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.