On Jan. 23, 2020, the new cluster of viral pneumonia cases originating in Wuhan, China, marked the third time in 20 years that a member of the large family of coronaviruses (CoVs) has jumped from animals to humans and sparked an outbreak.

In a new JAMA Viewpoint essay, Anthony S. Fauci, M.D., director of the NIHﾒs National Institute of Allergy and Infectious Diseases, looks back at two earlier novel CoV outbreaks that initially caused global havoc and describes steps needed to contain the current one.