White House press secretary says it is a 'false choice' to demand wealthy nations halt third doses in order to supply poor countries

Organization bemoans rich nations that used 'most of the global supply' of shots now 'using even more of it'

Director Tedros says further investigation of possibility needed, laments difficulties that experts had in accessing raw data in China

'A moral outrage': World Health Organization says wealthy states vaccinating younger people are costing lives in low-income nations

UN agency warns of 'catastrophic moral failure' of wealthy countries moving ahead with vaccinations while poorer areas are left behind

Emergencies chief says coronavirus is a worldwide 'wake up call' to prepare for something that could be even more severe

Tedros Adhanom Ghebreyesus laments 'dangerously short-sighted' cycle of spending vast sums to curb outbreaks but not preparing for the next epidemic

UN effort to get vaccines to poor countries hopes to get supplies by early next year; rich countries have reserved 9 out of 12 billion doses expected to be manufactured in 2021

'Herd immunity is achieved by protecting people from a virus, not by exposing them to it,' UN health agency chief Tedros Adhanom Ghebreyesus says

Former chief scientific adviser Mark Walport says that like the flu, the coronavirus 'almost certainly will require repeated vaccinations' to contain