Does exposure to COVID-19 protect against reinfection early on in recovery?

Bottom Line:

Infection with SARS-CoV-2 was shown to protect against reinfection during the early recovery phase in rhesus monkeys.


Deng, W. et al. Primary exposure to SARS-CoV-2 protects against reinfection in rhesus macaques. Science (2020). DOI: 10.1126/science.abc5343

Date Published:

2 July 2020


There have been reports of patients who recover from COVID-19 illness and have undetectable levels of virus, who subsequently test positive on a later test. Therefore, concerns have been raised about the possibility of a “relapse” or “reinfection” with COVID-19 after patients have recovered from an initial infection with the virus. A study was done in rhesus monkeys to determine whether an exposure to SARS-CoV-2 (the virus causing COVID-19) protects against reinfection with the same viral strain (i.e. a specific subtype of the virus). Adult monkeys were initially challenged with a SARS-CoV-2 strain, and after undergoing a mild-to-moderate course of illness, transitioned into the recovery stage. They were then re-challenged with the same dose and strain of SARS-CoV-2, 28 days after the initial challenge. Signs and symptoms were monitored at different time points of the study, including temperature, body weight, virus distribution, and chest X-ray. After being re-challenged with SARS-CoV-2, the monkeys did not appear to be reinfected during their early recovery stage. The authors of this study suggest a future study to determine whether the initial infection also protects against reinfection after a longer time-frame.

Summary by: Caroline Gregory