Pandemics do not die—they fade away. And that is what covid-19 is likely to do in 2022. True, there will be local and seasonal flare-ups, especially in chronically undervaccinated countries. Epidemiologists will also need to watch out for new variants that might be capable of outflanking the immunity provided by vaccines. Even so, over the coming years, as covid settles into its fate as an endemic disease, like flu or the common cold, life in most of the world is likely to return to normal—at least, the post-pandemic normal.
Behind this prospect lie both a stunning success and a depressing failure. The success is that very large numbers of people have been vaccinated and that, at each stage of infection from mild symptoms to intensive care, new medicines can now greatly reduce the risk of death. It is easy to take for granted, but the rapid creation and licensing of so many vaccines and treatments for a new disease is a scientific triumph.
The polio vaccine took 20 years to go from early trials to its first American licence. By the end of 2021, just two years after sars-cov-2 was first identified, the world was turning out roughly 1.5bn doses of covid vaccine each month. Airfinity, a life-sciences data firm, predicts that by the end of June 2022 a total of 25bn doses could have been produced. At a summit in September President Joe Biden called for 70% of the world to be fully vaccinated within a year. Supply need not be a constraint.
Immunity has been acquired at a terrible cost
Vaccines do not offer complete protection, however, especially among the elderly. Yet here, too, medical science has risen to the challenge. For example, early symptoms can be treated with molnupiravir, a twice-daily antiviral pill that in trials cut deaths and admissions to hospital by half. The gravely ill can receive dexamethasone, a cheap corticosteroid, which reduces the risk of death by 20-30%. In between are drugs like remdesivir and an antibody cocktail made by Regeneron.
Think of the combination of vaccination and treatment as a series of walls, each of which blocks a proportion of viral attacks from becoming fatal. The erection of each new wall further reduces the lethality of covid.
However, alongside this success is that failure. One further reason why covid will do less harm in the future is that it has already done so much in the past. Very large numbers of people are protected from current variants of covid only because they have already been infected. And many more, particularly in the developing world, will remain unprotected by vaccines or medicines long into 2022.
This immunity has been acquired at terrible cost. The Economist has tracked excess deaths during the pandemic—the mortality over and above what you would have expected in a normal year. Our central estimate on October 22nd was of a global total of 16.5m deaths (with a range from 10.2m to 19.2m), which was 3.3 times larger than the official count. Working backwards using assumptions about the share of fatal infections, a very rough estimate suggests that these deaths are the result of 1.5bn-3.6bn infections—six to 15 times the recorded number.
The combination of infection and vaccination explains why in, say, Britain in the autumn, you could detect antibodies to covid in 93% of adults. People are liable to re-infection, as Britain shows, but with each exposure to the virus the immune system becomes better trained to repel it. Along with new treatments and the fact that more young people are being infected, that explains why the fatality rate in Britain is now only a tenth of what it was at the start of 2021. Other countries will also follow that trajectory on the road to endemicity.
All this could yet be upended by a dangerous new variant. The virus is constantly mutating and the more of it there is in circulation, the greater the chance that an infectious new strain will emerge. However, even if Omicron and Rho variants strike, they may be no more deadly than Delta is. In addition, existing treatments are likely to remain effective, and vaccines can rapidly be tweaked to take account of the virus’s mutations.
Just another endemic disease
Increasingly, therefore, people will die from covid because they are elderly or infirm, or they are unvaccinated or cannot afford medicines. Sometimes people will remain vulnerable because they refuse to have a jab when offered one—a failure of health education. But vaccine doses are also being hoarded by rich countries, and getting needles into arms in poor and remote places is hard. Livelihoods will be ruined and lives lost all for lack of a safe injection that costs just a few dollars.
Covid is not done yet. But by 2023, it will no longer be a life-threatening disease for most people in the developed world. It will still pose a deadly danger to billions in the poor world. But the same is, sadly, true of many other conditions. Covid will be well on the way to becoming just another disease.