Where have you been? Whom have you met? Where have you eaten and shopped? The procedure for tracking the movements of people infected or potentially infected by the novel coronavirus (COVID-19) reads like a detective novel. The sleuths in this case are more than 700 medical professionals from Shanghai’s Center for Disease Control and Prevention. There is only one suspect — the highly contagious and sometimes fatal COVID-19 virus. Theirs is a race against time to try to prevent the virus from spreading. Every case must produce a preliminary report within the first 24 hours. Of the 353 confirmed coronavirus cases in Shanghai, one-third were identified through close contacts with other patients. That has involved nearly 3,000 investigations into the nearly 12,000 close contacts of existing patients. Most have since recovered and been discharged from hospital. Investigators must cope with vague memories and sometimes lies. An interview can take at least four hours as investigators trace a person’s every step in the 14 days prior to showing symptoms and beyond. Investigators often need to be patient to wheedle out the information they need. They also need to be adept at spotting liars. Copyright: (c) 2020 Shanghai Daily. PHOTO: A woman wearing a protective face mask is seen on a crossroad following the outbreak of coronavirus disease (COVID-19), in downtown Shanghai, China March 17, 2020. REUTERS/Aly Song