While the exact source of that is still unknown, most specialists concur that once a person acquires the virus, whether they have symptoms or not, they will have some level of immunity because they will produce defence mechanisms in the form of antibodies.
However, how exactly do those antibodies function and, more importantly, how long do they actually last? Amesh A. Adalja, M.D., a senior scholar at the Johns Hopkins Center for Health Security, advises against changing your behaviour based on the findings of an antibody test if you have recovered from COVID-19 or if you suspect but aren’t sure that you were infected. What you need to know is as follows.
What exactly are antibodies?
According to the National Institutes of Health, when your body detects a foreign invader, such as bacteria or viruses, it works to prevent infections by producing antibodies, Y-shaped proteins made by your white blood cells to combat the dangerous pathogens (NIH).
This contains the new coronavirus SARS-CoV-2, which produces COVID-19. Almost everyone with a healthy immune system will acquire IgM and IgG antibodies after infection, which can be identified with a serologic test (more commonly known as an antibody test).
Within a week or two of contracting the infection, IgM antibodies are typically produced earlier in the illness, but they quickly disappear, according to Suzanne Willard, Ph.D., clinical professor and associate dean for global health at Rutgers School of Nursing, who previously spoke with Prevention.com. IgG antibodies don’t begin to form until around six weeks have passed, although they last longer.
How long does it take coronavirus antibodies to develop?
According to the CDC, antibodies can sometimes be seen in persons within a week of contracting COVID-19. Others may require up to three weeks for the development of antibodies following viral infection.
Therefore, according to Dr. Adalja, “ideally, you’d wait three weeks after you had symptoms before getting an antibody test.” If you have acquired the virus at that stage, both IgM and IgG antibodies should be discernible, according to the CDC.
How much time do coronavirus antibodies last?
Dr. Adalja claims that the situation is still quite uncertain. Being exposed to COVID-19 twice is “extremely uncommon,” according to the CDC, which implies that antibodies may provide “at least temporary immunity.”
However, a recent Chinese study that was published in the journal Nature Medicine raises the possibility that the protective proteins may not last for very long. The researchers came to the conclusion that in persons who recovered from a SARS-CoV-2 infection, antibody levels “start to fall within two to three months,” particularly for those who never experienced symptoms.
Despite the limited size of the study—37 symptomatic and an equal number of asymptomatic patients were examined—the researchers feel their findings demonstrate the dangers of issuing COVID-19 “immunity passports.”
Unfortunately, there isn’t enough information to know if someone can contract COVID-19 again after being exposed to it once (similar to how you can get the flu each year). According to Dr. Adalja, “We don’t know what antibody level correlates with being protected from re-infection.” “We don’t know how long these antibodies remain and if they entirely protect people from reinfection, or only if they can help keep people from developing symptoms again if they’re re-infected,” says a spokesperson for the World Health Organization. According to him, it is also unknown if those who have COVID-19 antibodies can develop the virus and transfer it to others.
So, you’ve tested positive for COVID-19 antibodies,what now?
Antibody testing is “not 100% reliable, and some false positive results or false negative results may occur,” the CDC emphasizes. Therefore, it is conceivable to test positive for COVID-19 antibodies while not really possessing them.
Dr. Adalja’s explanation for this is that different coronaviruses, including some that cause the common cold, can infect people. Thus, results may be skewed if you felt sick but never had a COVID-19 case that was confirmed. Additionally, because your immune system is still constructing a response, antibodies may not be detected at all if you are only in the early stages of an active infection.
Additionally, there are various tests that can be used, but not all of them are reliable, according to Rama K. Mallampalli, M.D., chair of the Department of Internal Medicine at The Ohio State University Wexner Medical Center. “On this virus, we only have data going back six months. A positive antibody test simply indicates that the virus has been exposed to you.
Therefore, even if you’ve tested positive, the CDC still advises taking the necessary precautions to stop the virus from spreading, especially since many states are experiencing an increase in the number of confirmed cases. This entails keeping a six-foot space between yourself and those outside your home, avoiding people who seem ill, frequently washing your hands, disinfecting frequently touched surfaces, and donning a face mask in public—at least until a vaccine is available.
Is having antibodies preferable to not having them? Maria Gennaro, M.D., a professor of medicine at the Rutgers New Jersey Medical School, says, “I believe so. But it’s unclear how protective these really are.