Coronaviruses are part of a large family of viruses. Four types cause minor illnesses like the common cold, while other coronaviruses have triggered far more devastating impacts like SARS and MERS. Coronaviruses are zoonotic, meaning they jump from animals to humans.
In late December 2019, reports emerged of a novel coronavirus outbreak connected with pneumonia cases at a wildlife market in Wuhan, China. COVID-19, the disease caused by this novel coronavirus, spread across the nation within weeks—and then stormed its way across the world. By March 11, more than 118,000 cases were reported in more than 110 countries—including significant outbreaks in Italy, Iran, and South Korea—with 4,200 deaths worldwide. At that point, the World Health Organization labeled COVID-19 a pandemic.