COVID-19 reinfections—cases where individuals are infected with COVID-19, recover fully, and are reinfected after 90 days—have become increasingly common with the emergence of new strains of the virus called “variants.” The Centers for Disease Control and Prevention (CDC) is monitoring ongoing studies of COVID-19 to understand the frequency, timeline, severity, transmission rate and risk factors associated with reinfections. Vaccination remains highly effective in preventing severe illness caused by COVID-19 infections and reinfections.
In a recent article titled “Epidemiology of reinfections,” epidemiologist and biostatistician Dr. Katelyn Jetelina (MPH, PhD) explores COVID-19 reinfection using data collected in the United Kingdom. Dr. Jetelina highlights the significant increase in reinfections seen in the U.K. since the introduction of COVID-19 variants such as omicron. Reinfections accounted for just one percent of all cases in the U.K. prior to omicron, then increased to 11 percent during the omicron surge and now sit at 25 to 27 percent, according to national data collected in the U.K. Additional U.K. surveillance data shows reinfections are most common in unvaccinated people, young people ages 10 to 14 and 15 to 19, and those who had a mild primary infection with a low viral load or did not report symptoms at all during their first infection.
For more information about reinfections in the U.S., explore the resources available on the CDC Reinfections and COVID-19 page.* For data specific to Washington state, consult the Department of Health Reported COVID-19 Reinfections in Washington State document published July 6, 2022.
*This page was last updated January 20, 2022. Some information may not reflect current vaccination guidance. For current guidance around COVID-19 vaccination, please visit the CDC Stay Up to Date with Your COVID-19 Vaccines page.