The World Health Organization chief called Tuesday for investigators into the Covid-19 pandemic's origins to delve deeper into a theory about a possible lab incident, which they all but ruled out. "Although the team has concluded that a laboratory leak is the least likely hypothesis, this requires further investigation, potentially with additional missions involving specialist experts, which I am ready to deploy," Tedros Adhanom Ghebreyesus said in a briefing to WHO member states about the investigators' long-awaited report after an international mission to Wuhan, China. The WHO chief also voiced concern that the international team had difficulty accessing raw data during the mission, adding: "I expect future collaborative studies to include more timely and comprehensive data sharing." rjm-nl/jxb