n the last few days, major powers have responded to the horrific crisis unfolding in India. The US government’s decision to share 10m vaccine doses within weeks, and up to 50m more over the summer, is welcome and urgently needed. New Zealand, Norway and France have also responded to the demand for vaccines to be shared fairly around the world. But frankly, no country is acting on the scale that is necessary. This pandemic is a long way from over. The scenes in India, where Covid-19 continues to overwhelm health systems and sink the economy, are harrowing. In many countries, hospitals are flooded with patients and face shortages of vital medical supplies. At a global level, I fear the worst is yet to come. Across the world, there have been almost 100,000 reported deaths in the 10 days since the global total passed the 3m mark. Because of a lack of data collection, the true figure is likely much higher. Each death is a tragedy, the loss of a loved one, an untold story. Why, when we have vaccines and treatments for Covid, are we still seeing horrific reports of this virus raging through communities? The responsibility for this lies with global political leaders. While science has made significant progress, producing vaccines, treatments and tests in record time, the G20 have failed to come together and back the sustained global response that is desperately needed. This puts our hard-won scientific progress at risk. Science is only useful if it’s delivered to society. Until vaccines and tests for Covid are available to everyone, we won’t be able to stop this pandemic and its devastating consequences. Ensuring the world’s population has access is the best way to drive down transmission, reduce deaths and prevent dangerous new variants from emerging. It is simply not acceptable that while an estimated one in four people in high-income countries have received a Covid vaccine, just one in 500 have received the jab in low-income countries, or that hospitals in poorer countries are still struggling to access basic supplies like oxygen, sedatives and PPE. Healthcare workers in every country, who are putting themselves at risk to protect us all, must be first in line for vaccinations. Right now, global political leaders are the only people who can make these essential resources available. Rich countries – including the UK and US – have bought up the majority of existing vaccine supplies. They urgently need to start sharing these doses with the rest of the world, alongside national rollouts in their own countries, and through the Covax programme. And they must set out a timetable for how these donations will be increased as they vaccinate more of their populations domestically. The UK is in the perfect position to lead these efforts through its G7 presidency. Half of our population – including those who are most at risk from Covid – have had at least one dose of the vaccine. In fact, the UK has given almost as many doses to its own citizens as Covax has been able to ship to 120 countries in dire need of jabs. Covax and the Access to Covid-19 Tools Accelerator are ready to make vaccines and vital medicines available where they are most needed, but they can only deliver these with real support from political leaders. Vaccinating the whole world isn’t just the morally right thing to do – it’s in every nation’s scientific, public health and economic self-interest. The shores Covid now rages upon may seem distant to some, but the reality is that so long as the virus continues to spread in other countries, it continues to be a threat to everyone. If we allow Covid to keep spreading, it will go on evolving, increasing the risk of new variants that could cross borders and evade vaccines and treatments. With global infections at an all-time high, this is a very real risk. We are playing with fire. The first vaccines cannot be the preserve of the rich. At the same time, science needs to keeps pace with the evolving virus and develop the next generation of vaccines that will protect against future waves and variants. This will require building up manufacturing capacity globally, and combining all the tools needed to fight the virus: public health, honest communication, tests, sequencing, oxygen, PPE, treatments and vaccines. We have made remarkable progress in developing the crucial first vaccines, treatments and tests over the last year – driven in large part by the work of the ACT-Accelerator. This initiative still needs $19bn (£13.5bn) to finish driving the science forward and ensure these benefits are distributed equitably around the world – a tiny amount compared to the trillions governments are spending on stimulus packages to address the economic consequences of Covid. If countries who can afford to share choose not to, this pandemic will drag on, resulting in more deaths, suffering and economic hardship. We’re in danger of creating a fragmented, unequal world of haves and have-nots, where it will be far harder to come together and address the shared challenges of this century. We can exit this crisis and turn Covid into a treatable and preventable disease in 2021. But we’ll only be able to do this if all countries benefit equitably from scientific advances in treating the virus, and if science has sufficient support to keep up as the virus evolves. There can be no more delays or excuses. The longer we wait, the worse it will be for all of us. The world’s political leaders have a choice to make. It should be an easy one. Dr Jeremy Farrar is director of the Wellcome Trust, a global charitable foundation