As COVID-19 cases sweep the globe, doctors have mobilized for the unprecedented healthcare crisis, often lacking proper resources, facing wartime-triage situations, and dealing with their own emotions.

We talked to hospital doctors in several coronavirus hotspots — the U.S., the U.K., Italy, Belgium, and South Korea — to hear what it’s like for them as they treat patients and what they’re learning about the virus. They shared a range of experiences, but one key message kept coming through, one thing they want us all to know: The lockdown measures are working, so continue social-distancing and washing your hands.

“All the infection control measures actually are really, really, really the most important things,” Marta Zatta, an infectiologist at the ASU GI hospital in Trieste, Italy, told VICE News. “Because, intubated and ventilated…we are too late. We have to arrive before that.”

And the control measures definitely apply for young people, too. Dr. Gert de Keersmaecker, senior clinical fellow at a London hospital, said what’s shocked him most is the number of young people getting really sick from coronavirus and needing to go on ventilators. “I’ve never seen things like that.”