Betacoronavirus, Coronavirus Infections/drug therapy, Pneumonia, Viral/prevention & control, Pandemics/prevention & control, Coronavirus Infections/epidemiology, Coronavirus Infections/complications, Chloroquine/therapeutic use, Health Systems/organization & administration, Primary Health Care/organization & administration, Americas/epidemiology, Risk Groups, Vaccines, Vulnerable Populations, COVID-19, Ghebreyesus, Tedros Adhanom