Americans are being urged to leave their homes only for essential needs. For some, even a quick grocery run could mean the difference between life and death.

COVID-19 Messengers, an effort launched on Instagram by Emmalyn Sullivan, a 26-year-old New Yorker, pairs volunteers willing to run errands with people who are too vulnerable to venture outside, making it a little easier for them to stay safe at home. It has drawn participants around the world.