The United States has passed 500,000 COVID-19 deaths, by far the highest toll in the world. The morbid milestone comes as new COVID-19 cases continue to fall across the country amid an accelerating vaccine rollout, but the head of the World Health Organization is calling on rich countries not to undermine efforts to get vaccines to poorer nations by buying up billions of doses â in some cases ordering enough to vaccinate their populations more than once. âThe inequities that weâve seen here are just absolutely stunning,â says Dr. Craig Spencer, director of global health in emergency medicine at Columbia University Medical Center, who urges advanced economies to share their vaccine stockpiles with poorer countries in order to end the pandemic sooner. âItâs in our public health interest, itâs in our economic interest, and, I think most importantly, itâs really in our ethical and moral compass to be doing this.â