1. How many people have been reinfected?
A tracker maintained by the Dutch news agency BNO News had recorded 24 cases globally as of Oct. 16. The first confirmed case, a 33-year-old man from Hong Kong, was reported in August. He’d tested positive in March with mild symptoms of Covid-19, the disease caused by SARS-CoV-2, and had two negative tests a few weeks later. Four and a half months after the first event, he tested positive again, although he had no symptoms. The only known person to have died from a case of reinfection was an 89-year-old Dutch woman, who