The largest wholesale food market in Beijing was shuttered behind police guard and the surrounding neighborhood locked down Saturday after more than 50 people tested positive for the coronavirus in the Chinese capital. The outbreak — coming more than 50 days after the last local case in the city of 20 million people — showed how the virus can still come back as restrictions are eased. The city’s swift response reflected China’s emphasis on moving quickly to stem the spread of new cases wherever they appear, a lesson learned from fighting the outbreak earlier. “The epidemic was already almost over, and then suddenly ... (full story)