In a potential boost to global vaccine supplies, a Chinese COVID-19 vaccine has been granted emergency use by the World Health Organization.China's state-owned drugmaker Sinopharm is the first vaccine by a non-Western country to win WHO backing on Friday.It's also the first time the WHO has given emergency use approval to a Chinese vaccine, for any infectious disease. Sinopharm is one of two main Chinese coronavirus vaccines already being given to hundreds of millions of people at home and abroad. The WHO emergency listing is a signal to regulators that the product is now considered safe and effective.The listing also allows it to be included in COVAX. That's the global program providing vaccines mainly to poor countries struggling with vaccine supplies. The WHO said in a statement, "It's easy storage requirements make it highly suitable for low-resource settings."Director-General Tedros Adhanom Ghebreyesus spoke on Friday. "This afternoon, WHO gave emergency use listing to Sinopharm Beijing's COVID-19 vaccine, making it the sixth vaccine to receive WHO validation for safety, efficacy and quality. This expands the list of vaccines that COVAX can buy, and gives countries confidence to expedite their own regulatory approval, and to import and administer a vaccine."The WHO estimates Sinopharm's efficacy to be 79% for all age groups. It recommended the vaccine for adults aged 18 or older, in a two-dose schedule with a spacing of three to four weeks. In the COVAX program, Sinopharm's vaccine now joins those developed by Pfizer/BioNTech, AstraZeneca, Johnson and Johnson, and as of last week, Moderna.But a WHO official said it would be up to Sinopharm how many doses it chooses to provide the program. The WHO also said it could reach a decision on Sinovac China's other main COVID-19 vaccine by next week.