Despite great progress in healthcare, much of the world is still blighted by preventable disease, with the poorest people suffering the most. Over nine million people fall ill with TB and about 600,000 die from malaria each year, while five African countries have more than 15% of their adult populations living with HIV. The good news is that tackling these diseases turns out to be an extraordinary good investment.
It may sound cold-hearted to set health priorities based on cost-effectiveness, but it's actually the best way to do the most good in the world with limited resources. 193 governments are working on a set of priorities for the world to focus on by 2030, and the final list will be decided in New York by September of this year. To help the right decisions to be made, my think tank, the Copenhagen Consensus Center, has asked sixty teams of top economists to assess some of the key targets which have been proposed and make a case for which should be part of the final list.
Health is a big topic, and we've had the perspectives of five expert groups plus a number of commentaries. The case they make for tackling killer diseases is a strong one.
Take TB. Two billion people worldwide carry the bacterium that causes it, and 1 in 10 of them will go on to develop the disease. TB probably killed about 100 million people over the 20th century, and was one of the major killers before antibiotics became available. The success of this treatment has almost wiped out TB in rich countries, but it continues to be a disease of the poor, and kills about 1.5 million each year. The global risk of dying from TB has been reduced by more than one-third over the past twenty years, and since 1995, the progress is estimated to have saved 37 million people from dying. Yet, further progress has been hampered by weak health systems, poverty and multi-resistant strains of TB. Despite the toll it takes, TB treatment receives just 4% of total development assistance spent on health, compared with 25% for HIV.
TB can be difficult to detect, particularly in countries with poor health systems, and the World Health Organization recommends a preventative course of drugs, costing just $21 per person, for high-risk populations. Treatment is highly effective and on average can give people a further 20 years of productive life. Helping almost everyone who's sick will cost about $8 billion a year, but provide benefits worth almost $350 billion. Each dollar spent this way will generate $43 worth of benefits.
Malaria is another killer disease. 90% of those it kills are in sub-Saharan Africa, and 77% are children under five. By far the most effective treatment is to use a drug called artemisinin. Like all widely-used drugs, there is a danger that malarial parasites will develop resistance to it, so it is crucial to delay resistance by using artemisinin in combination with one or more other malaria medicines. In total, this will likely cost about half a billion dollars but have benefits of twenty billion dollars, or about $36 worth of benefits for each dollar spent.
But what about HIV/AIDS? Treatment with anti-retroviral drugs has made an enormous difference to people with HIV infection, but it continues to cause large-scale human suffering in sub-Saharan Africa, where 70% of the global population of HIV positive people live. Globally, 35 million people live with HIV. The team studying this disease estimates that the current use of anti-retroviral drugs should be expanded - doubling the amount spent on it - to reach all those people with significantly weakened immune systems.
This is not a cheap option, needing another $10 billion annually, but reaching 90% of the target group of patients would save many lives and be cost-effective. Every dollar spent would give benefits (extra years of life) valued at $10. And this is not the only option. Male circumcision is a one-off treatment, which can reduce the transmission of HIV to men during intercourse by 60% and, with some delay, also reduce transmission to women. Although not as effective as widespread drug treatment, the cost would be about $30 million annually but provide benefits of almost a billion dollars per year. Each dollar spent would return $28 worth of benefits.
However, one of the economists working on this project has proposed a radically different approach. Her argument is that focusing on a handful of key diseases has created islands of excellence in a sea of dysfunction.
Much better, she suggests, to build up strong health systems which can deal with all medical problems. The problem is that the cost is phenomenally higher and the efficiency per dollar likely much lower. However, it is worth remembering that there are bigger problems than the 4 million killed by AIDS, TB and malaria - take working-age injury and trauma, which kills almost 6 million each year.
In the health sector, we are spoilt for choice of good projects to spend money efficiently - and transform people's lives. Now it's up to the world's governments to look at the evidence and make good choices on priorities for the next fifteen years. The lives of millions of people depend on it.