Those with weak immune systems can now receive a third dose of the COVID-19 vaccine through GS’ CARES team, after CDC recommendations that the immunocompromised receive booster shots.

“People with moderately to severely compromised immune systems may not build the same level of immunity to 2-dose vaccine series compared to people who are not immunocompromised,” according to the CDC. “Immunocompromised are especially vulnerable to COVID-19, because they are more at risk of serious, prolonged illness.”

A third dose of of Moderna and Pfizer has FDA emergency approval. Those thinking they could use an additional dose to further protect themselves should contact the CARES team to schedule their third dose.

The additional dose is intended to improve immunocompromised people’s response to their initial vaccine series, and is not the same as a booster dose normally given after a vaccine’s immune responses have waned over time, according to the CDC.