COVID-19 Immunity After Infection: How It Works and How Long It Can Last

4 min read
COVID-19 Immunity After Infection: How It Works and How Long It Can Last

With all the news about Covid-19, it’s hard to keep up with the facts. Many people are especially interested in how immunity works after the infection and how long this immunity will last. People hope that coronavirus immunity will help them return to “normal life.” They want to know that they don’t need to be concerned about getting the virus again or possibly infecting someone else with it.


Unfortunately, there are a lot of things that are still unknown about this virus, especially when it comes to immunity to the virus. Nevertheless, there are some answers that we do have. 

How does immunity work after the infection?

To understand how Covid immunity works, you must first have some understanding of how viruses work and how your immune system responds to them.

You can think of a virus as a piece of genetic material that’s surrounded by a protein coating. These viruses are unable to reproduce unless they can find a host cell, which is why they seek out cells in the human body.

Once a virus enters your body, it will locate a cell to inject with its genetic material. It can then take over the control of that cell and begin multiplying.

To combat this process, your body’s immune system must work to destroy these infected cells. When your body first encounters a new viral infection, such as Covid-19, it will deploy T cells. Their job is to find and kill any cells that are infected with the virus. 

If the T cells are unsuccessful, the virus will continue to reproduce. Your body will then deploy B cells, which have antibodies that are better equipped to battle the infected cells.

After you’ve overcome the infection, antibodies to Covid will remain in your body. They’re there to help fight off any infection that may occur in the future. The length of time that these antibodies stay in your system will vary. For some illnesses, they’ll only be present for days, but for others, they’re present for a lifetime.

How long does immunity last?

Once you’ve recovered from this illness, research suggests that you should be immune to it for 5 to 7 months. However, such immunity may last even longer. It’s difficult for researchers to pinpoint how immunity works because there are still many things unknown about this disease. This is why there is only an estimate of how long immunity will last.

One thing that is known is that other types of coronaviruses, such as MERS, do induce immunity. Many of these viruses induce immunity for several years. Researchers are hoping that this current strain will behave in much the same way. It’s also important to understand that most of the studies regarding immunity to Covid focus on people who had a severe case of the disease and required hospitalization for their condition.


With so many unknowns, the Centers for Disease Control and Prevention and the World Health Organization say that more research needs to be conducted. However, if you have concerns that you or someone you love may have Covid, you’ll want answers now. If you live in San Francisco, California, BASS Medical Group can help.  Their elite team is made up of doctors who are experts in their respective fields.  Call (925) 350-4044 to learn more or schedule an appointment.