Since the beginning of the Covid, scientists have been seeking to understand immunity to Covid better. How long a person is immune after having Covid, after getting vaccinated, or both. And for booster shots, what could long-lasting immunity mean? It is too early to find out, but experts are getting closer to it.
According to Dr. Peter Marks, director of the US Food and Drug Administration’s Center for Biologics Evaluation and Research, the current thought around potential Covid vaccine boosters suggests they may be needed at some point. “We’ll have to see where this all interacts. Is it possible we’re going to need a booster at some point? Yes. Is it probable? Yes. Do we know exactly when? No,” Marks said. “But if I had to look at my crystal ball, it’s probably not sooner, hopefully, than a year after being vaccinated for the average adult.”
Expert emphasis anyone who is currently fully vaccinated should still be protected. The timeline for potential booster remains unclear because to collect data; scientists still need time on how long immunity against Covid may last in the future and how to factor in future variants.
When a person has immunity in general, they have protection against disease. One can get active immunity either through infection or vaccination. Antibodies are developed by the immune system either in response to the infection or induced by the vaccination. By the presence of antibodies, immunity is often measured. The immune system makes proteins to help fight infections in the blood. With a laboratory test, they can be determined. But the immune system is much more than antibodies; they include B Cells (which produce antibodies) and T-Cells (which target infected cells).
Currently, three Covid vaccines are authorized for emergency use in the US. The two-dose of Pfizer/BioNTech vaccines (ages 12 and older) and Moderna vaccine (ages 18 and older), and the single-dose Johnson & Johnson vaccine (ages 18 and older). The potential use of a booster all three companies are investigating. Vaccine makers are studying whether the immunity these vaccines develop lasts for an extended period or not, and the vaccine would protect from all the variants of Covid. If the vaccinated people would need to booster dose to stay protected?
In the latest study, researchers suggest that people who develop natural immunity after recovering from Covid can be long-lasting, possibly at least for a year. But that doesn’t mean such people shouldn’t get vaccinated. It doesn’t mean immunity will last forever. Bone marrow cells may maintain a memory of Covid for at least 11 months after someone is infected. Protective antibodies are found in these cells.