More than 540 million people have been reported to be infected with Coronavirus disease (COVID-19) globally, and over 1 million deaths, according to a recent tally by Worldometers. Infections have been reported in more than 210 countries and territories since the first cases were identified in December 2019. The USA leads the world in the largest number of infected cases with 87 million patients and the largest number of deaths at just over 1 million.
COVID-19 is an infection caused by SARS-CoV-2. COVID-19 usually causes mild to moderate symptoms and most patients recover without special treatment. In some cases, it can result in serious illness. When a person coughs, sneezes, speaks, sings or breathes, small liquid particles from their mouth or nose can spread the virus to other people. This includes both large droplets and small aerosols.