What is the best investment in the world?

Since 1994, the world has spent about $97.9 billion developing new tools to fight infectious diseases in poor countries, including vaccines, treatments, diagnostic tools, and prevention tools like bed nets for diseases like malaria.

That sounds like a lot of money, and it is. But the organization that came up with this figure, Policy Cures Research, also tried to estimate the benefits that the study would generate. They came up with a dollar figure, too: $49.7 trillion. The full investment would avert about 40.7 million deaths between 2000 and 2040, according to the report.

These are big claims that deserve scrutiny, but the claims hold up.

This finding is especially important now that major agencies such as the World Health Organization, the vaccine fund Gavi, and the Global Fund to Fight AIDS, Tuberculosis and Malaria are campaigning to raise funds. World leaders have yet to respond with sufficient investment. The resistance is understandable (it’s a lot of money), but it lacks foresight.

There are enormous benefits to be gained from investing more in developing treatments, drugs and vaccines for the world’s deadliest infectious diseases. We just need to do it.

The study focused on what Policy Cures calls “neglected diseases” – infectious diseases that primarily affect developing countries. The burden is enormous: Respiratory infections and tuberculosis accounted for 153 million years of healthy life lost in 2019, roughly double the number of people injured in car accidents worldwide.

Between 1999 and 2023, the report found, 183 new technologies targeting these diseases were approved. The report hired an outside firm, Avenir Health, to model how much death and disease have been reduced so far, using data from the Global Burden of Disease Study. In some cases, the authors had to extrapolate. Some technologies, such as the RTS, S, and R21 malaria vaccines, have only gained support from the World Health Organization in the past few years, so the authors estimated the benefits they would have if introduced.

In total, they estimate that these technologies could save 2.47 billion life-years (adjusting for future lives saved), or roughly 40.7 million lives saved. That’s a huge number.

Calculating the ROI of global health investments is difficult. First, you need to know what the investment will cost. The total cost spent so far on these technologies is $97.9 billion. Advancing promising tools currently in the “pipeline” that could be deployed by 2040 will cost an additional $24.8 billion, bringing the total cost to $122.7 billion.

Next, some judgment calls must be made to put a dollar value on the benefits gained.

The majority of the benefits come from saving lives and preventing disease. To calculate the ROI figure, you need to place a monetary value on the lives saved or diseases prevented and compare that value to the upfront investment costs. The report estimates a savings of $19,985 per year of healthy life. Multiplying this by the 2.47 billion years of life saved by these technologies equals approximately $49.4 trillion.

Adding in an estimate of the general economic benefits to communities from reducing the burden of illness on workers and dependents ($269.8 billion), the total benefits identified in the report are $49.7 trillion, or $405 for every dollar invested.

I would say that ROI is also underestimated.

The figure of $19,985 per year, which accounts for 99 percent of these benefits, is a variation of something called the “statistical life value,” and calculating it is one of the most complex and contentious exercises in economics.

Usually, that value is estimated by measuring how much individuals are willing to pay to reduce their risk of death. The idea is that people’s actual spending represents a more accurate indication of people’s feelings than, for example, opinion polls. But people in poor countries are willing to pay less than people in rich countries, for the obvious reason that they have less money. This approach tends to conclude that lives in poor countries are literally worth less. Lower. In fact, the Policy Cures report uses lower statistical values ​​for life expectancy for poor countries.

A subsection also calculates an estimate that assumes all lives are valued equally: applying the US value ($12.3 million) equally to all humans would result in an ROI of over $9,000 per dollar invested, but the report rejects this as “unrealistic and potentially harmful to the credibility of the project.”

I think $9,000 is a more realistic number. It would make sense for the Nigerian government, for example, to set a lower number. This statistic would allow policymakers to understand how much people are willing to pay to save their own lives.

But the main funders of malaria vaccine research are not poor country governments. They are wealthy country governments and foundations — in other words, groups in the Global North — who should value all lives equally.

While most of those billions of years of life have already been saved, some are yet to be saved. The report estimates that a malaria vaccine could save about 370 million years of life between now and 2040. But malaria vaccine rollout is just getting started. It took decades for the first vaccine, RTS,S, to be released, and even now advocates warn that funding is insufficient for universal rollout to all children who need the vaccine.

These vaccines may save 370 million years of life, but they may not. We need to invest in getting vaccines to those who need them.

This is an incredibly hopeful report. But it is also a call to action. Rich countries must act urgently, or this opportunity will slip through our fingers, and poor children in Africa and South Asia will pay the price.

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