Until we end COVID-19 transmission across the planet, we are likely to keep getting multiple COVID-19 “waves”— that is, rolling, recurrent outbreaks. While no public health expert has a foolproof crystal ball, this scenario of repeated waves means that the likely contours of the next one to two years are now coming into clearer view.

Right now, many countries including Italy, Spain, the United States, and the United Kingdom, are still struggling desperately to put out the initial fire. They are using suppression measures like stay-at-home orders as a fire extinguisher to smother transmission while urgently trying to ramp up their capacity to conduct testing, to manufacture and distribute personal protective equipment for health workers, and to treat people with COVID-19.

Once countries have achieved a sharp fall in new daily cases, protected all their health workers, scaled up their hospital capacity to deal with future COVID-19 outbreaks, and can conduct widespread and efficient testing, isolation of cases, and contact tracing, they can then start relaxing their lockdowns.

But even in this best case scenario, we are likely to see further outbreaks, and we may need to turn on the fire extinguisher again.

Turning the fire extinguisher on and off will buy us time until we develop a COVID-19 vaccine. If we develop a safe and highly effective vaccine, over time we will be able to vaccinate a high enough proportion of the world’s population to eliminate the risk of overwhelming epidemics. An effective vaccine will both prevent people getting COVID-19 and also curb transmission.

The good news is that the time from “lab to jab” could be as short as 12-18 months (though some experts predict it will take longer), a fraction of the time it took to develop an Ebola vaccine. Efforts to develop COVID-19 vaccines have been on the fastest trajectory in history. Just 63 days after China shared the genetic code of SARS-CoV-2, the virus that causes COVID-19, the first human trial began in Seattle, USA on March 16, 2020. Two days later a trial in China kicked off.

There are now at least 70 COVID-19 vaccines under development, including at my own university led by Bart Haynes at the Duke Human Vaccine Initiative. The Coalition for Epidemic Preparedness Innovations (CEPI), the Norway-based public-private partnership that develops epidemic vaccines, is aiming to mobilize $2 billion to make three vaccines available to the point at which they can be mass manufactured and deployed. The Biomedical Advanced Research and Development Authority (BARDA), part of the US Department of Health and Human Services, just announced a $1 billion partnership with J&J to accelerate development of J&J’s vaccine candidate.

The Bill & Melinda Gates Foundation will help fund factories ready to manufacture seven of the vaccine candidates currently under development, even though only one or two candidates are likely to be successful, a strategy that Bill Gates acknowledges will lead to billions being spent on the abandoned five candidates. Losing a few billion dollars, he argues, is worth it compared to the trillions of dollars being lost economically by COVID-19.

The more vaccine development efforts there are underway, the greater the odds that a vaccine will be available in 12-18 months. Governments, philanthropies, academics, and industry should do everything they feasibly can to reduce those timelines further, if at all possible.

But there’s also bad news on the vaccine front. There’s no guarantee right now that when COVID-19 vaccines are ready, they will actually reach everyone who needs them. There’s a serious risk that rich countries will monopolize the vaccine, leaving poor countries behind. Such behavior by the rich world would not only be immoral but disastrous to their own health and recovery too, and the selfishness would upend our global efforts to shut down the pandemic once and for all.

We’ve seen this happen before. During the 2009 swine flu pandemic, rich countries like Australia, Canada, and the United States secured large advanced orders for the vaccine from manufacturers, and as a result poor countries received vaccines much more slowly and in smaller quantities. They were unable to vaccinate as many of their citizens.

And we’ve already seen recent signs of monopoly behavior by the rich. The Trump Administration reportedly tried to buy the German firm CureVac, which is developing a COVID-19 vaccine—a New York Times story said that the attempted purchased raised “fears in Berlin that President Trump was trying to assure that any inoculation would be available first, and perhaps exclusively, in the United States.” A researcher at the University of Copenhagen who is developing a vaccine with public funding from the European Union has been approached with large financial offers from companies wanting to buy the rights to his research. And rich countries are trying to monopolize other vital supplies, including face masks and critical medicines that are used to treat patients in intensive care, like antibiotics, blood pressure drugs, and sedatives.

We need to put a plan in place to make sure that everyone worldwide who needs the vaccine will be able to receive it, free at the point of care. What would such a plan look like?

Based on typical vaccine development success rates, it is reasonable to assume that at least one or two vaccines currently under development will prove to be safe and effective in large randomized controlled trials. Manufacturing capacity will need to be built worldwide so that the vaccine can be produced in bulk quantities. For this to happen, companies that know how to make COVID-19 vaccines will need to widely share their knowledge. The Director-General of the World Health Organization, Tedros Adhanom Ghebreyesus has called on “all countries, companies and research institutions to support open data, open science, and open collaboration so that all people can enjoy the benefits of science and research,” including by voluntarily sharing intellectual property on COVID-19 medicines, vaccines, and diagnostics.

Let’s assume, optimistically, that a billion doses of vaccine—whether from one or more vaccine producers—will be ready for use in 2021. Governments worldwide should club together into a “solidarity purchasing club” to make a large advanced purchase commitment, with countries contributing according to their means, to buy these billion doses and fund their distribution for prioritized populations worldwide. The vaccine should then be made free to recipients at the point of care and accessible just like your typical flu shot.

For this to happen, we’ll need vaccine manufacturers based in rich and poor countries to work in partnership with each other. No sole manufacturer on earth will be able to single-handedly make enough vaccine. The manufacturing of any successful vaccine will need to be globalized as quickly as possible. All vaccine developers receiving public funds must be prepared to support the necessary technology transfer arrangements to manufacturers worldwide.

We’ll then need a worldwide allocation system that is fair, transparent, and tailored towards ending the pandemic. It would make sense, for example, for the initial doses to go first to health workers and to countries that have an uncontrolled epidemic, then to the elderly and medically vulnerable, and finally to the whole population.

The Geneva-based organization Gavi, the Vaccine Alliance, which currently funds vaccinations in 73 low- and middle-income countries, is already helping to get these countries ready for the roll-out of COVID-19 vaccines. With sufficient donations from the public, philanthropic, and private sectors, Gavi could buy enough vaccine for all 73 countries. Other funders like the World Bank and the Global Fund will need to help fund vaccine delivery efforts.

Which brings us to the multi-billion dollar question. How much cash will be needed to buy enough vaccine? This all depends on the price of the vaccine.

In the current pandemic situation, many vaccine companies are receiving public funding for their efforts and should not be seeking a profit or price gouging. We cannot expect them to take a big financial hit, of course, but they should ideally sell the vaccine on a break-even basis. The manufacturers should commit to making the vaccine available at a price low enough to ensure truly global reach.

Given J&J’s important partnership with BARDA, the company looks set to potentially be a key supplier of a vaccine. It was therefore encouraging to learn that if J&J’s COVID-19 vaccine effort is successful, the company will sell it on a not-for-profit basis. But the price that J&J is suggesting, of ten dollars a dose, would mean that the solidarity purchasing club would simply not be able to buy enough doses to distribute the vaccine to those who need it worldwide. Ten dollars would be just the price of the vaccine itself—there is an additional cost for the distribution. At a ten dollars per dose price, there would probably be no end in sight for the COVID-19 crisis.

Nobody can know so early in the development process what the final price of a new vaccine will be. It depends on many factors, such as how it is given (e.g. the number of doses), the complexity of the manufacturing process, and whether you need to add an ingredient called an adjuvant to boost the vaccine’s effectiveness. But when the world finally gets a safe, effective COVID-19 vaccine, fair allocation and fair pricing will be crucial for ending the COVID-19 pandemic.

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