Headlines claiming that humanity could go extinct by 2100 because of malicious artificial intelligence or nuclear war capture the new Lancet Commission report only in part. The document itself, as The Guardian describes it, is more interesting and more practical: it is an attempt to compile a list of threats in a way that can be used by those who allocate money and people.
What was measured
The commission's 35 experts modeled, for each of the 17 threats, how many years of healthy life humanity could lose to disease, disability or premature death. The metric is called DALY, disability-adjusted life years. The calculations were based on current trends and compared best-case and worst-case scenarios.
A threat made the list on two conditions: it had to have the potential to take away many years of life, and it had to have realistic paths to a solution. In other words, this is not a ranking of the scariest things, but a ranking of where intervention changes something. Ibrahim Abubakar, professor of infectious disease epidemiology at UCL, explained the logic this way:
"We are not coming from a position of 'we want to scare you.' We are coming from the position that if you are making policy decisions today, these are potential threats you may face, and this is the scale of change you can realistically achieve."
Extinction versus everyday arithmetic
Malicious AI, including for creating biological weapons, and nuclear conflict with the risk of nuclear famine are named in the report as extinction threats. The authors state directly that the probability of such events is low. The mechanism in the case of nuclear war is this: particles in the upper atmosphere block sunlight, and famine follows. The harm, if it were realized, would be, in the words of The Lancet's editorial, apocalyptic.
The rest of the list is less dramatic, but it is what adds up to the biggest losses. The "major catastrophic threats," which together could take more than a billion years of healthy life, include air pollution, antibiotic resistance, child undernutrition, climate, armed conflict, excessive alcohol consumption, high blood pressure, income inequality, low levels of education, natural pandemics, obesity, mental health, smoking and unhealthy aging. The risk of extinction here sits alongside what is already happening now.
The distribution depends on the region. In high-income countries, the main threats are noncommunicable diseases, including obesity and mental health problems. In low-income countries, health losses are linked, for example, to low levels of education.
The price of solutions in numbers
The report also offers applied estimates. If warming is limited to about 1.8 °C instead of 4.4 °C, the loss of 1.89 billion years of healthy life can be avoided. A collapse or sharp reduction in international health aid would cost up to 1.5 billion DALYs by 2100, and almost 70% of these losses would fall on sub-Saharan Africa. This comes against the backdrop of the US, the UK and other large donors announcing substantial spending cuts over the past year.
In other words, a decision on the aid budget made in a few capitals is, in this model, comparable in scale to climate policy. Child undernutrition also hits the same region hardest.
What has changed in this list
Commission co-chair Christopher Murray of the University of Washington said that three years ago they started with three obvious threats: conflict, climate and pandemics. Now there are 17. In his view, governments need money and personnel to anticipate, prevent and prepare for such a broad range of risks. The assessment is to be updated every year; the results will be presented at the World Health Summit in Berlin.
A skeptical caveat: these are model scenarios spanning 75 years, and their accuracy over such horizons is limited. What matters is not any specific figure but the order of magnitude and the approach itself, in which a threat is assessed together with what can be done about it.
The main question for the annual update: can the list influence budgets, and not just headlines? If next year the governments' responses to this report do not include at least one documented reallocation of funds to prevention, the 17 threats will remain a nice table.
