Amazon has started using thermal cameras—which return results faster and require less contact than regular thermometers—to test warehouse workers’ temperatures, Reuters reports. The cameras, in use in at least six warehouses in Seattle and Los Angeles, display a real-time picture of how much heat a body emits and can scan people en masse. If a scan does show an elevated temperature, the employee will be then be tested with a thermometer. The country’s second-largest employer is looking for fevers as an indicator of possible coronavirus infections as staff at more than 50 Amazon warehouses across the world have tested positive for COVID-19. Some workers have spoken out or organized strikes in protest of what they say is Amazon’s inadequate response to the virus. The online retailer has also been hit with record demand as tens of millions of people stay home and shop online.