The World Health Organization (WHO) is calling for a moratorium on Covid-19 booster jabs until at least the end of September to focus instead on getting more doses to poorer countries.
Dr Tedros Adhanom Ghebreyesus, the UN agency's director general, said the moratorium should allow 10 per cent of the populations of every country in the world to be vaccinated before booster campaigns began.
As it stands, richer countries have administered around 100 doses per 100 people - most vaccines require two doses for full protection - but lower income countries have only given 1.5 doses per 100 people.
"It's no understatement to say that the course of the pandemic depends on the leadership of the G20 countries," said Dr Tedros, calling for support with dose sharing and funding for the deployment of the vaccines from the world's richest nations.
The Telegraph understands that the UK is set to start giving booster doses to as many as 32 million people, possibly starting by the beginning of September. Israel, another near-fully vaccinated country, will start giving booster shots next week.
Dr Tedros said the flow of vaccines must change direction, to prioritise the people who are most in need and currently completely unprotected.
"We need an urgent reversal from the majority of vaccines going to high income countries, to the majority going to low income countries... To make that happen, we need everyone's cooperation," he added.
There has been a growing outcry about the glaring inequity of richer nations giving booster shots while many billions of people have not had any shots at all. Researchers have also pointed out that there is no data yet to show that the boosters are even necessary for most people.
Gian Gandhi, Covax coordinator at Unicef’s Supply Division - one of the key figures involved in distributing vaccines to poorer countries globally - told The Telegraph that he feared wealthy countries were set to repeat previous "selfish mistakes" already seen during the pandemic.
"We're very quickly about to enter a period where some countries are going to look to booster doses or look to childhood immunisations, and there's a very real risk that everything that happened 12 months ago happens again," he said.
"So certainly the best laid plans for Covax - both at a global level and country level - could be destabilised by countries continuing to kind of make the same sort of selfish mistakes that we saw in the earlier part of this year and the end of last year."
An internal WHO document, seen by Nature, estimates that if the 11 rich countries that are either rolling out boosters or considering it this year were to give the shots to everyone over 50 years old, they would use up roughly 440 million doses of the global supply.
The WHO maintains that these jabs would be better used in lower income countries, where roughly 3.5 billion haven't had a single vaccine.
Professor Gavin Yamey, a professor of global public health at Duke University in America, wrote on Twitter this week: "Global health" (whatever that is) no longer exists; it's over. It's rich nations for themselves now.
"At a defining moment that cries out for international collective action we're witnessing the opposite - a retreat to nationalism and the grotesque hoarding of vaccines by the wealthy."
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