Certain situations are almost impossible to train for. What do you do, say, when you nick an artery during surgery? Or spot a leak on an oil rig? In 2018, trauma surgeon Dr. Alex Young launched Virti, a training platform that drops workers into high-stress augmented and virtual reality scenarios, where they can practice responding and receive feedback. This year, the company found an important new use case: the pandemic. Virti’s COVID-19 modules teach frontline workers around the world skills like the right way to wear personal protective equipment, administer treatment or ventilate a patient. A company study found that Virti’s AR- and VR-based approach boosted knowledge retention by 230% compared with typical training. —Jamie Ducharme