‘This is not a discrete one-off episode’, warned ^[1] Jeremy Farrar, the head of Wellcome Trust, a global health research foundation. ‘[T]his is now an endemic human infection.’

Covid-19, as Farrar suggests, knows no boundaries, geographic, political or otherwise. Nor must our efforts to defeat it. No one can be truly safe unless the disease is tackled wherever it takes hold.

To prevent what many scientists now fear—a second wave of the pandemic later this year—we must urgently act where the need is most pressing: in the world’s poorest countries. As Abiy Ahmed, Ethiopia’s prime minister and a Nobel Peace Prize laureate, has warned ^[2], if the coronavirus sweeps through Africa, it will return to haunt us all.

Abiy is not understating the threat. The United Nations estimates ^[3] that Covid-19 could cost between 300,000 and 3 million lives in Africa. As many as 130 million people globally may be pushed to the brink of starvation ^[4] by a breakdown in global supply chains.

A successful exit strategy from this pandemic requires testing, treatments and a vaccine. And if developing countries cannot combat the virus effectively, we may be powerless to prevent further outbreaks around the world.

That risk is glaringly real. Of sub-Saharan Africa’s 45 countries, 34 spend less than US$200 per capita ^[5] annually on health care. In five countries, health spending is less than US$50. Countries have little testing equipment, few (if any) ventilators, limited medical supplies, and often poor sanitation and insufficient running water.

Moreover, workers cannot rely on social safety nets to support them during the pandemic. They therefore face a deadly choice: go to work and risk being struck down by the disease, or stay home and risk being condemned to starvation. This makes it difficult for these countries to use tools available to richer economies, such as social distancing, lockdowns and regular hand-washing.

If we are to stop Covid-19 in its tracks, our interventions will only be as effective as the weakest link in the global chain. So, if any issue is a candidate for multilateral global action, then it must be our response to this pandemic. The health of each depends on the health of all. Local solutions everywhere are only as good as the global response.

With this in mind, we must outlaw the ugly ‘vaccine nationalism’ that seems to be setting in. Restricting new vaccines to those who can afford them will condemn millions to enduring multiple waves of the illness. We must also crack down on medical piracy, whereby a few countries seek to monopolise testing kits, ventilators and personal protective equipment by whatever means, instead of joining a coordinated international effort to increase their global supply.

World leaders therefore must decide to finance a collaborative international search for a vaccine and its mass manufacture, and mount a concerted effort to increase our capacity to produce medical goods. And they must support developing countries in their hour of greatest need, which is now.

The world’s leading health experts tell us that they need US$8 billion ^[6] immediately to address the most critical gaps in the response to Covid-19. That is equivalent to just US$1 for every person in the world—and a fraction of the estimated US$14 trillion that has already been allocated to deal with the pandemic’s consequences. It is shocking that, while we have seen individual and corporate generosity in response to Covid-19, governments have so far been unable fully to fund this global health initiative with even that modest amount.

Indeed, US President Donald Trump has suspended US funding ^[7] of the World Health Organization. And, following the 19 April virtual summit of G20 health ministers, the US deputy secretary of health and human services could not sign on ^[8] to a joint statement promising what Trump had already agreed to ^[9] at the 26 March G20 leaders’ summit: a strengthened mandate for the WHO and sustainable funding for its emergency programs. A watered-down communiqué was issued instead.

Fortunately—and to their great credit—the European Union and five countries (the United Kingdom, France, Germany, Norway and Saudi Arabia) have agreed to fill the void, announcing a special pledging conference to take place on 4 May. This summit is the right way forward, as outlined in a mission statement on global health by French President Emmanuel Macron and as recommended in a recent letter ^[10] signed by 200 economists, health professionals, and former presidents and prime ministers.

And there will be much to decide. Despite help from Europe’s biggest aid donors and Saudi Arabia, CEPI (the Coalition for Epidemic Preparedness Innovations) is only one-third of the way to securing the US$3 billion it needs to develop, scale up and mass-manufacture hundreds of millions of Covid-19 vaccine doses.

Similarly, while the Wellcome Trust, the Bill & Melinda Gates Foundation and Mastercard have together provided ^[11] up to US$125 million of seed funding to speed the development of and access to life-saving treatment for the coronavirus, the plan for accelerating Covid-19 therapeutic interventions and vaccines ^[12] (ACTIV) needs US$2.25 billion ^[13] to make the first 100 million courses of treatment available. Expert organisations that monitor, improve and deliver diagnostic tests around the world, like the Foundation for Innovative New Diagnostics, also need our support.

My hope is that in the next few days, aid donors from Australia, New Zealand and South Korea to Canada and Mexico will join the pledging event, thus sending a message that the world will not stand for vaccine nationalism, medical piracy and a cutthroat race to the bottom. And the United States and China, which have both been helping countries bilaterally, should demonstrate their global leadership by joining the conference, instead of sitting it out.

The consequences of lapses in international cooperation over the last few months can now be counted in lost lives. Having failed to stop the first wave of Covid-19, we must not make the same mistake again.

Global interventions may feel far removed from the quotidian tasks we all face as individuals, families and communities in getting through this crisis. But if countries do not see beyond their borders and coordinate an international response, we will all suffer.

Today, the entire world is facing what Martin Luther King, Jr famously called ‘the fierce urgency of now’. With Covid-19 threatening to destroy millions of lives and livelihoods on every continent, King’s words were prophetic ^[14]: ‘In this unfolding conundrum of life and history, there is such a thing as being too late.’