Yale COVID-19 Data

COVID-19 Cases

Since August 2020, Yale has maintained various asymptomatic screening requirements and voluntarily testing options for students (undergraduate and graduate/professional), faculty, and staff. These data reflect positive COVID-19 cases from Yale’s asymptomatic testing program as well as positive cases by the same population from external tests sites that were voluntarily self-reported to Yale testing program. Beginning January 2022, Yale observed a significant increase in the number of self-reported external positives.

Effective April 22, 2022, the public dashboard has been updated to reflect this shift for January 2022 onward. The historic data from March 2020 – March 2022 from the Connecticut Data tabs is available for reference.

Positive cases are shown by date on which a test was collected. There is a 1-3 day delay between when tests occur and when results become available. These counts may change further as positives from external tests are reported for earlier dates. These counts include only unique positive cases, listed by the date of that individual’s first positive test within a 90-day period. An individual who becomes reinfected more than 90 days after a prior positive is counted as a new case.

Learn more about Yale’s testing program


total students in isolation

As of March 2, 2023

This includes all undergraduate, graduate, and professional school students isolating on campus, in residence, and off-campus.

Vaccination Rates

As of March 6, 2023


Undergraduate Students


Graduate & Professional Students





These vaccination rates are the percentages of individuals who are fully vaccinated and have submitted proof to the university. Learn more about Yale’s vaccination requirements.