GENEVA (Reuters) - The COVAX facility to distribute COVID-19 vaccines to poorer countries faces a “serious challenge” to meet demand, WHO Director-General Tedros Adhanom Ghebreyesus told a news conference on Thursday. “Last week, I made an urgent request to countries, with doses of COVID-19 vaccines that have WHO Emergency Use Listing, to share 10 million doses immediately with COVAX,” he said. “I requested manufacturers to help ensure that the countries that step up can rapidly donate those doses. This challenge has been heard but we’re yet to receive commitments for these doses. I’m still hopeful that some forward looking and enlightened leaders will step up,” he added.