Why are cases surging in countries that used Chinese vaccines?
by from CNN.com - RSS Channel - App International Edition on (#5KGP2)
Among more than 90 countries that are using Covid-19 vaccines from China, several countries have seen new Covid-19 outbreaks. Examples from these countries suggest that the Chinese vaccines may not be very effective at preventing the spread of the virus, but experts say they're not a total failure. CNN's David Culver has more.