What’s the ‘stealth’ omicron?

  • A medical worker wearing protective gear collects a sample from a resident at a coronavirus test site in Xichen District in Beijing, Tuesday, Jan. 25, 2022. Hong Kong has already suspended many overseas flights and requires arrivals be quarantined, similar to mainland China’s “zero-tolerance” approach to the virus that has placed millions under lockdowns and mandates mask wearing, rigorous case tracing and mass testing. (AP Photo/Andy Wong)

Scientists and health officials around the world are keeping their eyes on a descendant of the omicron variant that has been found in at least 40 countries, including the United States.