Ryan Bourne is Chair in Public Understanding of Economics at the Cato Institute.

Aside from death and disease, one spirit-crushing aspect of this pandemic has been the regularity of false lights at the end of the proverbial tunnel. The Delta variant is just the latest in a series of fresh hurdles we’ve faced in returning to “normality.”

News that vaccines, though apparently still highly effective against death and hospitalisation, may now be far less so against symptomatic infection from the variant adds another layer of uncertainty about what’s coming next.

UK Covid-19 cases have been around 30 times higher at times this August than this time last year. That’s not surprising given a transmissible variant and more “normal” behaviour now.

But it raises questions: what if vaccine efficacy against severe disease wanes over the coming months, with prevalence still high? Will widespread booster jabs or Delta-adjusted shots be needed? What happens when schools re-open in September?

Given there have been more twists in this saga already than a Chubby Checker dance class, I’m not going to predict how it will play out. But recent months have at least shown the contours of how we might ultimately “learn to live with Covid-19.” And re-reading The Great Barrington Declaration (GBD) recently, I was struck that although it had aged badly against events following its publication, it might provide wisdom in regards future policy.

The essential policy recommendation of the GBD, remember, was for normality for the non-vulnerable, but more “focused protection” for those at the highest death risk from Covid-19.

Published on October 4 2020, just as the more transmissible Alpha, English, or B.1.1.7 variant was taking off, its timing could hardly have been worse. Vaccines were just around the corner. Lives saved via “suppressing” the virus then were much higher in number and more certain than any lockdown efforts before.

Outside of care homes, where failures to protect the frail were shocking, “focused protection” of the type that the GBD envisaged wasn’t particularly viable anyway. There were 12.5 million people over 65 alone in 2020—almost 19 per cent of the whole population—and many more with other conditions.

Any government protective efforts to isolate these individuals would have been difficult to scale, and so unlikely to reduce risks much beyond precautions the vulnerable were taking.

Indeed, net risks to them would surely have increased: everyone else living normal lives would have increased the virus’s prevalence, and so people’s exposure to it, including in hospitals where many of the most vulnerable people find themselves.

So, while the GBD was right in highlighting the dreadful costs of the most draconian lockdowns and the inadequacies of nursing home protections, it underestimated suppression’s benefits and the difficulties of focused protection. If we’d followed its recommendations for winter, we’d have seen more disease and death than we experienced as the vaccination program was rolled out.

And yet…when the context changes, we should change our minds. Now, with high efficacy vaccines available to all adults, the GBD begins looking a much more sensible roadmap for policymakers.

For starters, it’s now clear that Zero Covid is a pipedream. Even if the virus could have been eliminated in isolated countries such as New Zealand, extinguishing it globally is impossible, necessitating closed borders indefinitely. Attempting to suppress it entirely now would be futile. The only thing guaranteed from strenuous efforts at elimination would be severe GDP downturns and lost living time again.

No, it’s now reasonably clear instead that the “end” here, as the GBD predicted, will be an endemic virus with localised herd immunity from vaccines and infection recoveries. Some theorise, in fact, that while our vaccines are very effective in protecting the inner body, they are much less so in protecting the nasal passage, meaning we could see symptomatic cases for lots of vaccinated people over time.

Everyone will see immunity top-ups through exposures or booster shots. The fact that many vaccinated people can be infected and transmit the virus severely undermines the case for narrow government-mandated “vaccine passports.”

The value of the vaccines then is that they appear to reduce the relative risks of severe disease or death to levels associated with colds or flu. We do not ordinarily invoke population-wide restrictions for such risks. So while people and businesses should of course be free to take further precautions if they wish, given their or their customers’ and workers’ wants and needs, a world of universal vaccine availability should not be one contemplating society-wide restrictions.

True, not everyone has been vaccinated yet (including children). And there are those who seemingly cannot be protected, perhaps because of compromised immune systems. Governments should allow parents, ultimately, to decide whether their children obtain the vaccines.

But for adults offered them who say “no thanks,” we face a question: what burdens, in the form of coercive mandates, should everyone bear to realise health benefits accruing overwhelmingly to those unwilling to protect themselves? The default answer should surely be “none.” In economics speak, the unvaccinated are now the “least cost avoiders” of the harm of the virus.

The still vulnerable–including the 500,000+ people (in England) who are immunocompromised or immunosuppressed—have a better claim to be protected. But the fact that the vaccine slashes risks broadly makes genuine “focused protection” of them now more viable.

These groups should be identified and allowed periodic antibody tests, as well as being prioritised for booster shots. Governments should provide them with a decent supply of N-95 masks, ensure they have access to regular at-home testing for guests, and consider monoclonal treatments. All these measures would be far less costly to society than stay-at-home orders, forced business closures, or reintroduced mask mandates for all.

Now you might say, “it’s easy to favour focused protection now!” Boris Johnson doesn’t want to row back to lockdowns; even Neil Ferguson and SAGE member John Edmunds think suppression won’t be necessary. But people will call for everything again if cases rise again significantly in Autumn.

Having lived through the past 18 months, it will be difficult for politicians and much of the public to make the psychological shift to treating Covid-19 diagnoses as an ordinary part of life, rather than a contribution to a national crisis.

But it seems clear we will need to make that shift. For though there might be other twists to come, Covid-19 appears likely to become endemic, with most of us exposed to it, and our vaccine technologies make this disease far less serious than it was before.

Rather than refighting the lockdown wars of 2020, these new circumstances require clear new public health principles. Whatever you thought of the GBD approach last year, the case for it now is far stronger.