Inadequate supplies of Covid-19 vaccines for lower-income countries mean it could take years to inoculate some parts of the world, undermining global efforts to end the pandemic.

Desperate to vaccinate their populations against Covid-19, high-income nations, home to about 1bn people, have secured 4.2bn doses, approximately 74 per cent of total government orders, according to the latest weekly data compiled by the Global Health Innovation Center at Duke University of North Carolina. In contrast, lower-middle and low-income countries have secured orders for only 675m doses.

The shortfall means that while the UK aims to offer coronavirus vaccinations to all adults in Britain by September, in many parts of the world it could take as long as three years to inoculate the population during which time the virus will continue to circulate, experts have warned.

“We have a catastrophic supply problem [in low-income countries],” said Anna Marriott, health policy manager at Oxfam GB. “The longer the virus is able to travel the world, the greater the risk of mutations and the greater the risk that the vaccines we do have will become ineffective.”

Column chart of Confirmed number of doses purchased by country income level classification (million) showing Poorer countries fall behind in race for vaccines

Many low and lower-middle-income countries had planned to rely on the WHO-backed Covax facility, set up last year with Gavi, an alliance of vaccine partners, and the Coalition for Epidemic Preparedness Innovations, a foundation that takes donations to fund independent vaccine research.

The programme aimed to ensure the equitable, worldwide distribution of 2bn Covid-19 vaccine doses by the end of 2021. Poorer countries would get doses for free and no country would vaccinate more than 20 per cent of its population before every country had been given the same opportunity.

But Covax has struggled to mobilise the support needed from wealthy nations to subsidise the initiative. It has only secured orders for 1.07bn doses so far, while rich nations have preferred to sign bilateral supply deals.

“It’s not right that younger, healthier adults in rich countries are vaccinated before health workers and older people in poorer countries,” Tedros Adhanom Ghebreyesus, head of the World Health Organization said this week in a searing critique of rich countries and their response to the coronavirus pandemic.

Aurélia Nguyen of Gavi told the Financial Times that Covax had “line of sight” on 1.97bn vaccination doses and was on track to meet its goal of fair and equitable access to vaccines for developing countries. However, she declined to say how many doses would be delivered this year. This would depend on production volumes and on regulatory approval in each country where vaccines will be used, she said.

The uncertainty over Covax has forced developing economies and regional blocs such as the African Union into the commercial market to compete for their own supplies.

“The global situation we’re in is that we’re having to do what rich countries did earlier, hedging our bets with multiple bilateral [deals],” said Fatima Hassan, founder of Health Justice Initiative, a South African group seeking equitable access to vaccines.

“The company plays god,” Ms Hassan said of the vaccine manufacturers and the non-disclosure agreements that govern sales and mean that pricing information and supply volumes have remained closely guarded. “They fuel a lack of transparency . . . it shows quite clearly where power lies in this pandemic.”

Kate Elder, senior vaccines policy adviser at Médecins Sans Frontières, said that low-income countries faced “an artificially induced supply constraint”, explaining that a more collaborative approach to intellectual property could have made it easier for supplies of successful vaccines to be ramped up by other manufacturers.

“[Rich governments] enabled shortages by dumping funding into pharmaceutical companies without conditionality,” Ms Elder said. “We should be mandating the sharing of technology and knowhow to competent manufacturers, but we haven’t done that.”

One exception is the production of AstraZeneca’s Covid-19 vaccine by the Serum Institute of India, which is set to provide important supplies for many developing economies. The deal is a consequence of the partnership between AstraZeneca and Oxford university, in which Oxford sought to ensure that “those countries who are most vulnerable to the worst effects of this global pandemic have early access to a vaccine”.

Carlos Felipe Jaramillo, the World Bank’s vice-president for Latin America, said he feared that the region would find itself in the worst of both worlds: behind high-income countries with the purchasing power to secure large quantities of vaccines, but not eligible for schemes such as Covax.

In Peru, one of the countries hardest hit by the virus where more than one in every 1,000 people has died of Covid-19, the government secured agreements this month for 38m doses from China’s Sinopharm and 14m doses from AstraZeneca. Talks with Pfizer, however, have stalled over the drugmaker’s request for a liability waiver that would absolve it of responsibility for any side effects. Pfizer did not immediately respond to a request for comment.

“A number of the presidents have told me how difficult it’s been,” Mr Jaramillo said. “These pharmaceuticals are asking for some very difficult conditions that might require changing legislation in the countries . . . I don’t think this will be smooth and quick.”

Additional reporting from Joseph Cotterill in Johannesburg, Michael Stott in London, Michael Peel in Brussels, Gideon Long in Bogotá and Andres Schipani in Nairobi