At the risk of sounding like a newlywed presenting my spouse with a list of pointers for improvement, these once-miraculous Covid vaccines could do better. It wasn’t long ago that I celebrated the anniversary of being fully vaccinated, but that first flush of immunity started to wane very quickly. I’ve even been flirting with some exciting new variants.

I shouldn’t joke. The vaccines were indeed spectacularly effective, as well as being as safe as one could hope. But the virus has adapted so quickly that it is at risk of leaving us behind. The current vaccines were tuned to induce immunity to early strains of the Sars-Cov-2 virus, but more recent variants have proved adept at evading both the vaccines and the immunity from earlier infections.

The vaccines still dramatically reduce the risk of severe symptoms. But they do not eliminate the risk of infection, illness or lasting side-effects. Infection rates in the UK today may well be higher than they have ever been. The result: short-term illness, the risk of long-term illness and, for the unlucky, hospitalisation or death.

We can cope with that, if we have to. But there is clearly a risk of something nastier down the track. The UK has been hit by three consecutive waves of Omicron variants, each one appearing in a matter of weeks. If a future variant proves much more dangerous, we will not have much time to brace for impact.

So what can be done? The answer: develop better vaccines. The simplest approach is, as with flu, to try to predict where the virus will be four to six months ahead, and to make booster doses accordingly. That looks feasible. After scaling up to meet demand for vaccines in 2021, the world has “unprecedented production capacity”, says Rasmus Bech Hansen, founder of Airfinity, a health analytics company — enough to produce another 8bn doses this year.

But better, if we can figure out how to do it, is to make a vaccine that targets all Sars-Cov-2 variants, or a wider family of coronaviruses including Sars or, even more ambitiously, all coronaviruses. “It’s a riskier and more aggressive approach,” says Prashant Yadav, a vaccine supply-chain expert at the Center for Global Development, a Washington-based think-tank. There are several such vaccines in development; if one of them works, that’s a huge step forward.

Another approach that has recently been in the spotlight is a nasally administered booster. Akiko Iwasaki, an immunologist at Yale University, leads one of several laboratories working on such an approach, which she calls “prime and spike”. The nasal spray promises to produce antibodies in the nose, thus preventing infection before it starts and breaking the chain of transmission. But this vaccine is still at an early stage.

Other delivery mechanisms include patches and pills. It would be vastly easier to store and distribute a vaccine in tablet form, and many people would prefer to swallow a pill than have a jab.

A final consideration, says Yadav, is to develop new ways of manufacturing vaccines — for example, growing them in plant or yeast cultures. Having such alternatives available would avoid bottlenecks the next time a vaccine is urgently needed.

This is all very exciting, and Bech Hansen says there are around 400 different Covid vaccines at various stages of development, along with more than 100 new flu vaccines and over 250 vaccines for other diseases.

There is far more urgency than there was before Covid, but less urgency than we need. Given the risk of a further dangerous variant (not small) and the social benefit of an effective vaccine against it (huge), governments should be investing much more to accelerate the next generation of vaccines.

In 2020, government programmes such as Operation Warp Speed in the US aimed to subsidise research, testing and production of vaccine candidates, as well as dramatically accelerating the process of regulatory approval. The idea was that governments, rather than private companies, would accept the risk of failure. This made sense, because it was society as a whole that would enjoy most of the rewards.

A vaccine manufacturer certainly profits from a successful vaccine but those profits are dwarfed by the wider benefits. By accelerating vaccine development and production, Operation Warp Speed “saved hundreds of thousands of lives and trillions of dollars”, says Alex Tabarrok, an economist at George Mason University.

The stakes are lower now but still unnervingly high. While there is plenty of interesting science happening in the vaccine pipeline, it will not be fast enough if we are unlucky with the next variant. To move next-generation vaccines beyond promising studies into clinical trials then large-scale production will take money, as well as a greater sense of regulatory urgency. It is possible these new vaccines will all fail or that they will succeed but provide only a modest benefit.

Or they may prove essential. Investing more money in the next Covid vaccine is not only likely to create scientific spillovers for other vaccines but is the best way we have of reducing the risk of disaster. Such insurance is worth paying for. Politicians have been keen to declare that the pandemic is over but the virus pays no attention to such proclamations. We need even better vaccines. We should be willing to pay for them.

Tim Harford’s new book is ‘How to Make the World Add Up’

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