Patients with COVID-19 outside of Wuhan, China, shed the virus for a median of 17 days, according to a retrospective cohort study published yesterday in the International Journal of Infectious Diseases.Also, a study in the same journal found that third-generation transmission of the COVID-19 epidemic likely began on Jan 17 to 20 in Wuhan, then spread to the rest of Hubei province from Jan 23 to 24, while the mixed first- and second-generation transmissions interacted to worsen the outbreak.Shedding virus for as long as 6 weeksIn the first study, researchers studied the clinical factors, lab results, treatments, and outcomes of 147 adult COVID-19 patients in a single hospital in Changsha, China, the capital of Hunan province, which is