A version of this article originally ran in The Brink.

Before leaving the house, we’ve all gotten used to double-checking that we have four essential items: phone, keys, wallet, mask. After two exhausting years of living in a pandemic, grabbing a mask (or two) on the way out the door has become a routine part of our mental checklist. 

But at this point in the pandemic, many people are wondering if it’s safe to ditch mask-wearing in schools, offices, and other indoor places, or if COVID-19 will ever fade away. According to BU epidemiologist Ellie Murray, the answer is complicated—and very much depends on the actions we take collectively. Even if COVID-19 transitions from a pandemic to an endemic disease—where infections occur in seasonal or predictable cycles, like the flu—that does not necessarily mean we’ll be mask-free or that vaccinations will no longer be needed.

To move from a pandemic to endemic, says Murray, a BU School of Public Health assistant professor of epidemiology, the world needs “to have some predictable sense of where that disease is going to go next.” COVID-19, she says, will likely remain prevalent for the foreseeable future, but we have the public health tools—like testing and masking—to continually monitor and manage it.

In this video, Murray explains the difference between pandemic and endemic, how we might learn to live with COVID-19 in the future, and why she sees reason to be optimistic.