The failure to provide even and equitable access to the vaccines is heightening this risk by allowing the virus to continue spreading freely among some of the globe’s poorest and most vulnerable populations, the experts say.
In a survey of 77 scientists from 28 countries, carried out by the People’s Vaccine Alliance, two-thirds said they believed the world had a year or less before Sars-Cov-2 mutated so that most first-generation vaccines were rendered ineffective and modified jabs were required.
Almost a third of those surveyed gave a timeframe of nine months or less.
The overwhelming majority (88 per cent) said that persistent low vaccine coverage in many countries would make it more likely for vaccine-resistant mutations to appear.
Fewer than one in eight said they believed that mutations would never render the current vaccines ineffective.
Under current global vaccination rates, only 10 per cent of people in most poor countries will be vaccinated by the end of the year, according to the alliance, which is a coalition of more than 50 aid charities and other organisations campaigning for equitable vaccine access.
Devi Sridhar, professor of global public health at the University of Edinburgh, said: “The more the virus circulates, the more likely it is that mutations and variants will emerge, which could make our current vaccines ineffective. At the same time, poor countries are being left behind without vaccines and basic medical supplies like oxygen.
“As we’ve learned, viruses don’t care about borders. We have to vaccinate as many people as possible, everywhere in the world, as quickly as possible. Why wait and watch instead of getting ahead of this?”
Nearly three-quarters of those surveyed said manufacturers needed to share technology and intellectual property to increase global access to the Covid-19 vaccines.
Many vaccines are being produced by developed nations, which have already ordered the vast majority of doses due to be delivered this year, leaving poorer countries short of supplies.
The world’s richest countries have bought a billion more doses than their citizens need, according to research. The UK has amassed one of the largest vaccine stockpiles in the world, having ordered more than 400 million shots – enough to inoculate its entire population three times over.
Experts fear the uneven distribution of supplies could have global repercussions in the fight against Covid-19.
“Unless we vaccinate the world, we leave the playing field open to more and more mutations, which could churn out variants that could evade our current vaccines and require booster shots to deal with them,” said Gregg Gonsalves, associate professor of epidemiology at Yale University.
“We all have a self-interest in ensuring that everyone around the world, no matter where they live, have access to Covid-19 vaccines. The virus doesn’t respect borders, and new variants somewhere on the planet mean none of us are safe.”
Earlier this month, rich countries blocked a proposal to waive intellectual property rights for Covid-19 vaccines, which would have allowed manufacturers in lower-income nations to access the technology needed to produce supplies.
Global Justice Now, a campaign group on issues of trade, health care and justice, said factories across the world were lying idle because of a patent system that prevents them from offering assistance.
Humanitarian medical organisation Médecins Sans Frontières accused countries that were blocking the proposals of being hypocritical. “Preventing poorer countries from having the best opportunity to respond to the crisis is really unforgivable,” it said.
Studies suggest the current generation of Covid vaccines remains effective in providing protection against needing hospital treatment and death from the coronavirus variants detected so far.
However, scientists fear that new mutations could emerge in the virus that are capable of evading immunity triggered by natural infection or vaccination.