Europe and the US are likely to face a Covid-19 variant that can defeat existing vaccines, a senior World Health Organisation official has said.
Dr David Nabarro, the WHO's special envoy for the disease, said some wealthy countries could pay the price for rushing to vaccinate their own people while poorer nations were left short of doses.
Countries would be better served by keeping infection rates low around the world, meaning the virus has less opportunity to mutate, he said.
Less than 5 per cent of people in low-income countries have received a first dose of vaccine, while rich nations are pressing ahead with booster shots and vaccination programmes for children.
Dr Nabarro told an Institute for Government event that the disparity in vaccinations could lead to resentment.
“My view is it’s pretty likely that there are going to be variants emerging that will beat the vaccines that are being used in Europe and the US,” he said.
“I will take the view that the people of Britain, or Europe, or the US, are best served if the level of virus in the world is kept as low as possible.
“We’re all going to depend on each other at various points in dealing with this. If we don’t deal with it as a global challenge, what’s likely to happen is that there will be a great deal of resentment and mistrust.”
Dr Nabarro said the WHO was monitoring a subvariant of the Delta strain known as AY.4.2, which is on the rise in England.
It has been designated a variant under investigation and appears to have a “modestly increased growth rate”, UK health officials said.
The UK has recorded a sharp increase in infections but the government has so far resisted calls to intervene by mandating mask-wearing or telling people to work from home.
“Right now, we are pretty lucky in that most of the mutants that are moving around, particularly the Delta, are not defeating the protection offered by vaccines,” Dr Nabarro said.
“But there’s a variant of the Delta that’s coming along, and we’re looking at that very carefully.”
Dr Tedros Adhanom Ghebreyesus, director general of the WHO, last week raised concerns over the disparity in inoculation rates among health workers around the world.
He said 80 per cent of health workers were fully vaccinated in high-income countries, compared with fewer than 10 per cent in Africa.
The WHO estimates that about 115,000 health workers have died from Covid-19 up to May 2021.