Two guests aboard the Celebrity Millennium tested positive for Covid-19 in required end-of-cruise testing, the cruise line said in a Thursday news release. Celebrity Millennium -- the first major cruise ship allowing American passengers since the pandemic forced a pause on the industry -- set sail on Saturday. The two positive guests, which shared a stateroom on the ship, are asymptomatic and are now in isolation while being monitored by a medical team, the release said. "We are conducting contact tracing, expediting testing for all close contacts and closely monitoring the situation," the news release said. The ship is sailing...