Jane Heffernan and John Glasser
Modelers have responded to the outbreak of respiratory illness caused by a novel (new human pathogen) coronavirus that emerged in China, but has since spread to other countries, by evaluating potential mitigation measures (e.g., contact-tracing, quarantine, isolation, social distancing). Currently, most infections elsewhere are among travelers from China, with some person-to-person spread among their close contacts. Should transmission be sustained in those communities, however, a global pandemic likely will result. Symptoms range from mild to severe, including death. Infectiousness seems to be re- lated to symptom severity, but infected people may be infectious before developing symptoms and those whose infections are asymptomatic may be infectious. While this complicates control, it is possible to detect infections via laboratory testing, facilitating contact-tracing and quarantine.