As some European and Asian nations have started easing lockdowns due to the coronavirus pandemic, experts have warned that despite the economic pain, social distancing measures remain necessary until a vaccine is developed.
Globally the virus has infected 3.7 million people and killed more than 260,000 - a quarter of them in the US. So far, more than 73,000 Americans have died of Covid-19, and Tom Frieden, former director of the Centers for Disease Control and Prevention, predicted the US toll could top 100,000 by the end of May. "Until we have an effective vaccine, unless something unexpected happens, our viral enemy will be with us for many months or years," Mr Frieden told a congressional hearing.