What does it mean to be “yellow”? (8/6/21)

A Message from the COVID-19 Coordinator


  • Why we moved to yellow alert status
  • What you can do to protect yourself

Dear Members of the Yale Community,

Yesterday, Provost Scott Strobel and Senior Vice President Jack Callahan wrote to faculty and staff to provide updates about the university’s vaccination program, testing requirements, and compliance policies. In their messages, they also indicated that, as of August 9, the university plans to move to the yellow alert status. In my message today, I will provide you with some additional information about this decision and what it means for you.

Why are we “yellow”?

Last year Yale, like many peer institutions, created a color-coded alert system, ranging from green to red, to inform the community of the state of COVID-19 infections on our campus and the measures that the university and all of us should take to reduce the risk of COVID-19 transmission. For many weeks this summer, we have been at the “green,” or lowest risk alert level, because numbers of infections were low on our campus and in the surrounding community and our on-campus population was small and relatively stable.

We are now at a time when infections on campus, while still at a relatively low level, have increased. Additionally, yesterday the Centers for Disease Control and Prevention (CDC) placed New Haven County in the “high” COVID-19 transmission category, and the Connecticut Department of Public Health issued related guidance. Given these conditions and because many faculty, staff, and students will be coming to campus from all over the country and the world, we have set the campus alert level to yellow. Doing so is intended to remind all of us of the measures we can take to keep our campus as safe as possible.

While current circumstances warrant additional caution, we should remember that we are at a very different place than we were last year at this time:

  • Vaccines have become widely available, and vaccination has proven to be an extremely effective measure to prevent COVID-19 infection. “Breakthrough infections” are infrequent in the vaccinated, and serious infections leading to hospitalization of vaccinated individuals are extremely rare.
  • After slowing in recent months, rates of vaccination across the country are once again accelerating.
  • Rates of vaccination in our own campus population are high and likely to increase further in the coming weeks; these high rates of vaccination in our community will not only protect vaccinated individuals but greatly reduce the risk of viral transmission to others.
  • Non-vaccine protective measures, such as masking and asymptomatic testing, were very effective in keeping rates of infection low on our campus last year when vaccines were unavailable; these same measures, when coupled with vaccination, will add substantial protection against viral transmission even with the more infectious Delta variant.

Still, additional caution is called for because:

  • The Delta variant, which is now responsible for the majority of cases of COVID-19, is highly transmissible: it spreads more easily and more rapidly than other variants.
  • While vaccinated individuals are much less likely than those who are unvaccinated to become infected with the Delta variant, the CDC has reported that, if vaccinated individuals do become infected, they are just as likely to transmit the virus to others as an unvaccinated, infected individual.
  • Vaccination rates, while on the rise, still vary considerably across the country.
  • Gatherings, particularly those indoors and those involving a mix of vaccinated and unvaccinated individuals, remain high-risk settings for transmission of COVID-19.

What should I do now?

As we learn more about the Delta variant and as we gather additional information about the rates of vaccination on campus and beyond, it is very important that you:

  • Get vaccinated if you have not yet done so.
  • Participate in asymptomatic testing if you are required to do so.
  • Get tested and isolate if you have any COVID-related symptoms, even if you are vaccinated—do not come to campus until you receive a negative test result. If you receive a positive test result, consult your health care provider or call the Campus COVID Resource Line (203-432-6604).
  • Wear a mask when indoors on campus and in public locations whether or not you are vaccinated; if you are unvaccinated, wear a mask at outdoor gatherings.
  • Avoid large social gatherings if possible, especially if they are indoors and the vaccination status of the attendees is unknown.

Finally, please know that Yale’s public health and medical experts are monitoring pandemic conditions closely and continuously. As we prepare to move forward with our on-campus academic activities while employing the health and safety measures described above, we are also prepared to ease requirements and restrictions associated with the yellow alert status if we do not see significant outbreaks or transmission on campus in the coming weeks. Our ability to move to “green” relies upon your ongoing diligence and that of our entire campus community.

Thank you again for your extraordinary efforts.

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