The call to stop COVID-19 vaccine boosters is the strongest yet from the UN agency as the gap between inoculation rates in wealthy and poor countries widens."I understand the concern of all governments to protect their people from the Delta variant. But we cannot accept countries that have already used most of the global supply of vaccines using even more of it," WHO Director-General Tedros said.High-income countries administered around 50 doses for every 100 people in May, and that number had since doubled, according to WHO. Low-income countries have only been able to administer 1.5 doses for every 100 people, due to lack of supply."We need an urgent reversal, from the majority of vaccines going to high-income countries, to the majority going to low-income countries," said Tedros.