What to know if you’ve had a COVID-19 infection

A Message from the COVID-19 Coordinator


  • Testing, immunity, and boosters after a COVID-19 infection
  • Brief updates about vaccines
  • Find up-to-date information at COVID.gov

Dear Members of the Yale Community,

While the Centers for Disease Control and Prevention’s (CDC) Community Level for New Haven remains low, we know that new COVID-19 infections continue to occur. This past week, we have seen increases, albeit small, in the numbers of infections and hospitalizations in New Haven, and several clusters of infections, frequently related to travel, among members of our community.

In today’s message, I will address questions frequently asked by those who have recently recovered from a COVID-19 infection. I will also share some brief updates on other COVID-19 topics.

I had COVID-19 in the past three months; what do I need to know?

Those who have recently been infected with COVID-19 often have questions about when and how to test, whether to get a booster shot, and whether infection provides immunity from the virus.

Can I get infected again?

Unfortunately, the answer is yes. Reinfection with COVID-19, while not common soon after an initial infection, can occur, especially if a new variant becomes prevalent. Not only does protection against another infection following a COVID-19 infection (or vaccination) wane over time, it may also be less effective against infections from new forms of the virus.

It is important to remember that vaccination, especially with boosting, remains highly effective against serious illness, hospitalization, or death from COVID-19.

Should I test for COVID-19 within 90 days after an infection? When and how?

In general, anyone who has tested positive for COVID-19 should not undergo asymptomatic polymerase chain reaction (PCR) testing for the next 90 days. Because the PCR test is highly sensitive, it may amplify and detect inactive viral material left behind after an initial infection and lead to a false positive result.

However, if you experience any symptoms consistent with COVID-19, you should get tested, ideally with a rapid antigen test (RAT). RATs are readily available without a prescription at most pharmacies. Because more virus must be present for the RAT to detect the specific COVID-19 target antigen and produce a positive result (compared to a PCR test), it is advisable to repeat the RAT in 24 hours if you are symptomatic and your first RAT result is negative. A positive RAT result is an indication that you are infected and that you can likely infect others, so it’s critical to isolate if you test positive.

Does COVID-19 infection boost my immunity?

Yes, infection will transiently increase your defenses against the virus once you have recovered. In addition, some research suggests that infection after vaccination enhances the protection from vaccination, producing what is sometimes called “hybrid immunity.” However, it is unknown how long this increased protection lasts.

Should I still get a booster shot, and when?

As noted above, it’s unclear how long the protective effect of infection after vaccination might last, so the CDC recommends that eligible individuals get boosted, even after an infection. The CDC advises that people should wait at least until symptoms resolve, and the isolation period is over, before getting their booster. Individuals may consider waiting up to 90 days after infection to get boosted. If you have questions about the timing of your booster, you should consult with your primary care provider.

Brief COVID-19 updates

  • You can schedule both your first and second booster shots, as well as a primary vaccine series, online through the Yale COVID-19 Program or at one of many sites throughout Connecticut.
  • Updated guidance on international vaccines can be found on the Yale Health website.
  • The federal government recently launched a new website, COVID.gov, that provides COVID-19 information about your community and a “COVID-19 Tool Kit” with links to resources for tests, treatments, vaccines, and free masks.

Living with COVID-19 in our midst requires us all to stay well-informed and to take advantage of the many tools for prevention and treatment that are now available. I will continue to update you with new guidance and recommendations as they emerge. In the meantime, thank you for your continued care for yourselves, your classmates, your colleagues, and our community.

Stephanie S. Spangler, M.D.
Vice Provost for Health Affairs and Academic Integrity
Clinical Professor of Obstetrics, Gynecology and Reproductive Sciences
University COVID-19 Coordinator