The world would be better protected against new Covid variants and there would be substantially fewer deaths in low and middle-income countries if rich nations donated half of their vaccine doses, new research suggests.
The modelling study found it was in wealthy nations’ self-interests to donate doses because vaccine inequity would prolong the pandemic and increase the risk of new variants developing.
The research found if high-income countries donated 46% of their Covid vaccine supplies, low and middle-income countries would see a significant decrease in virus deaths – but that even small increases in vaccine donations would have a disproportionately beneficial effect.
Just over 5% of people in low-income countries are fully vaccinated compared to 72% in high-income countries.
Qingpeng Zhang, an associate professor at the City University of Hong Kong and a lead author of the study, said it was understandable that richer nations sought to secure doses to protect their own populations first before distributing vaccines to other countries.
But, Zhang said, the “benefits to the high-income countries of preserving or stocking up vaccines isn’t as significant as they would have expected, because that’s only very short-term protection”.
“People didn’t take into consideration the future viral mutations that will break through the protection built by existing vaccines.”
The modelling was based on aviation data that tracked human movement internationally – and predicted what would happen over five years with different vaccine allocation strategies.
It showed inequitable vaccination would lead to a faster drop in mortality in high-income countries in the first year, but that in subsequent years the countries would become vulnerable to re-infection and new waves of Covid.
The team began the research before the rise of the Delta and Omicron variants – developments that reflect the study’s predictions.
“Both of those new strains emerged from middle- and low-income countries,” Zhang said. “If, at first, those countries got sufficient vaccines to protect their populations, then probably those new strains could have been contained.”
The research found that when richer nations donated vaccines only to their neighbours there was only a limited benefit.
“It would be better to have a global allocation instead of a regional allocation,” Zhang said.
Australia has distributed 18m Covid vaccine doses to neighbouring countries but committed zero doses to the Covax initiative, a World Health Organization-backed fund that aims to equitably distribute vaccine doses globally.
In December, a group of scientists and aid organisations – among them the Doherty Institute, the Burnet Institute and the Coalition for Epidemic Preparedness Innovations – asked the Australian government to commit an additional $250m in funding for Covax, called calling the vaccination gap “unfair, immoral [and] dangerous”.
In March 2021, an international survey of epidemiologists found that 88% said persistent low vaccination rates in many countries would make it more likely for vaccine-resistant strains to develop.
Prof Michael Good, head of the laboratory of vaccines for the developing world at Griffith University, who was not involved in the modelling study, said the research quantified the benefits of equitable vaccine distribution and highlighted the need for long-term thinking when it came to vaccine decision-making.
“If we make decisions as a country today about how we use vaccines, that can have an impact on variants that are going to develop in one, two, three or five years’ time,” Good said.
“This paper says: don’t just give them to your nearest neighbours, give them to all lower-middle income countries equally, because you don’t know where the next variant of concern is going to come from.
“We make decisions that will certainly affect the health of people in low-income countries, but it will also affect our health in high-income countries in the next three to five years as well.”
The study was published in the peer-reviewed journal Nature Human Behaviour.
