For the past three months, this metropolitan area of nearly five million people, the capital of the Australian state of Victoria, has been under one of the world’s tightest lockdowns. You may leave home only if shopping for essential items, meeting medical needs, providing care, taking up to two hours of daily exercise, and going to work if it is impossible to work from home. Travel of more than five kilometres (3.1 miles) from home, or across the boundary of the metropolitan area, is prohibited. Police hand out heavy fines to violators.

The Victorian government ordered the lockdown on July 5, after a day in which the state, which has a population of 6.7 million, recorded 191 new Covid-19 cases—the state’s highest daily total since the pandemic began. The outbreak peaked at 723 new cases on July 30 and then began to fall. By October 4, the 14-day moving average had dropped to 12.

At the time of writing, the state has had over 20,000 cases and 800 deaths. All the other Australian states together have had fewer than 7,000 cases and under one hundred deaths, making it possible to hope that Australia could eliminate the virus, as neighbouring New Zealand has come close to doing.

No major political party opposes the lockdown. Organised protest rallies were sparsely attended, perhaps because police warned protesters that they could be fined—and many were. Protesting is not one of the permissible reasons for leaving home.

When faced with a highly contagious disease that puts vulnerable people at risk, few Victorians are moved by abstract calls for ‘freedom’ coming mostly from younger people who are at lower risk. Most accept that the lockdown is necessary because it saves lives. And the steep decline in the number of new cases and deaths during the lockdown suggests that it does prevent deaths from Covid-19.

But that is only part of the picture. In the United Kingdom last month, 32 scientists signed a letter to Prime Minister Boris Johnson pointing to the significant harms that lockdowns cause—harms that, they suggest, may exceed the benefits. The scientists cite an estimate from Cancer Research UK that the lockdown has led to two million delayed cancer screenings, tests, or treatments, which could cost as many as 60,000 lives—more than the UK’s 42,000 Covid-19 deaths so far.

Cancer is only one cause of death that the lockdown is likely to increase; there are likely to be many others. But without a lockdown, the number of deaths from Covid-19 could end up being many times greater than the present toll. There are also other ways in which the lockdown saves lives. In Australia, for example, it appears to have virtually eliminated deaths from seasonal flu, saving about 400 lives in the first half of 2020, compared to the same period last year.

A group of researchers led by Olga Yakusheva, a University of Michigan economist, has sought to estimate the net number of lives saved (or lost) by pandemic-mitigating policies in the US in 2020. The team finds that these public-health measures saved between 913,762 and 2,046,322 lives, but also could result in an ‘indirect collateral loss’ of 84,000 to 514,800 lives, implying 398,962 to 1,962,322 net lives saved. That is a wide range, but still clearly a positive outcome.

Yakusheva and her coauthors seek to avoid contentious ethical issues by taking into account nothing but the number of lives saved or lost. That avoids three key issues that a more adequate assessment of the costs and benefits of lockdowns should face.

First, an adequate assessment would not disregard the difference between dying at 90 and at 20, 30, or 40. As I have contended previously, we should be counting years of life lost or saved, not simply lives.

Second, as Michael Plant and I argued earlier this year, the impact of lockdowns on quality of life matters, too. Lockdowns cause widespread unemployment, for example, and that sharply reduces life satisfaction. Difficult as quality of life is to measure and quantify, a proper accounting of the costs and benefits of lockdown cannot just wave it away.

Third, and perhaps most important of all, we must consider the impact of lockdowns on people who even in normal times are struggling to meet their and their families’ basic needs. Governments of countries where many people live in or on the edge of extreme poverty have particularly strong reasons to avoid lockdowns, but governments of developed countries also ought not disregard altogether the fact that a recession in the advanced economies jeopardises the very survival of people in other countries.

Until this year, extreme poverty had been dropping steadily for the past 20 years. So far in 2020, it has risen by 37 million people. How much of that is caused by lockdowns, rather than by the virus itself, is difficult to say, but the part played by lockdowns would surely be significant.

According to Henrietta Fore, executive director of the United Nations Children’s Fund, at the height of the pandemic, 192 countries had closed schools, leaving 1.6 billion children without in-person learning. For many, learning remotely would not have been a possibility. At least 24 million children were projected to have left school permanently. For many girls, that is likely to mean early marriage instead of the prospect of a career. The New York Times recently reported that school closures, combined with the economic hardship caused by the lockdowns, have caused a big increase in child labour in low-income countries.

Even if lockdowns do save lives in the countries that institute them, that isn’t sufficient to show that it is the right path for a government to take.

—Project Syndicate