Tedros Adhanom Ghebreyesus, WHO director-general, told a Geneva news conference on Friday that 189 countries were participating in the programme.
WHO expects to make decisions on whether to give emergency use approval to vaccines from Pfizer, Moderna and AstraZeneca in coming weeks, its chief scientist Soumya Swaminathan said on Friday.
She said the global health body could decide on Pfizer's vaccine candidate in the next "couple of weeks", and later said it could also review Moderna's and AstraZeneca's in a few weeks. WHO approval could allow a vaccine to be deployed in some countries where national medical regulators have not yet been able to evaluate it.
Meanwhile, the overall number of global Covid-19 cases has topped 69.4 million, while the deaths have surged to more than 1.58 million, according to Johns Hopkins University.
In its latest update on Friday, the University's Center for Systems Science and Engineering (CSSE) revealed that the current global caseload and death toll stood at 69,496,859 and 1,580,727, respectively.
Source: NDTV