Rich countries are opening up societies and vaccinating young people who are not at great risk from COVID-19, while the poorest countries cruelly lack doses, the World Health Organization said on Friday, condemning a global failure, Reuters reports.

The situation in Africa, where new infections and deaths jumped by nearly 40% last week compared to the previous week, is "so dangerous" as the Delta variant spreads globally, WHO director-general Tedros Adhanom Ghebreyesus said.

"Our world is failing, as the global community we are failing," he told a news conference.

Tedros, who is Ethiopian, chastised unnamed countries for reluctance to share doses with low-income countries. He compared it to the HIV/AIDS crisis, when some argued that African nations were unable to use complicated treatments.

"I mean that attitude has to be a thing of the past," Tedros said. "The problem now is a supply problem, just give us the vaccines."

"The difference is between the haves and the have nots which is now completely exposing the unfairness of our world - the injustice, the inequality, let's face it," he said.