A "dream team" of the world's top economists has recommended that global governments spend money on combating HIV/AIDS before tackling issues such as climate change.

The economist panel, which included three Nobel laureates, met in Copenhagen last week to decide on the 10 biggest challenges facing the world.

The conference, known as the Copenhagen Consensus, was organised by Denmark's Environmental Assessment Institute - led by controversial and outspoken critic of the Kyoto Protocol Bjorn Lomborg.


The panel's work was premised on the theory that if global governments had an extra US$50 billion ($79 billion) to spend to improve the world, what should they do first?

The idea of using a cost/benefit analysis to prioritise world spending on aid issues sprang from Lomborg.

The challenges rated as the world's top 10 included communicable disease, malnutrition and hunger, water and sanitation, subsidies and trade barriers, governance and corruption, financial instability, climate change, migration, education and conflict.

At least one of the panel of economists said that the task stretched cost/benefit analysis to its limit, and that there was not enough information available on the challenges to make accurate decisions about what action to take.

But by the end of the week-long conference, the panel released a list of what should be done first.

Combating HIV/AIDS was at the top. The panel estimated that 28 million cases could be prevented by 2010 at a cost of US$27 billion ($43 billion) - with benefits projected to be as large as 40 times that figure. The HIV/AIDS problem was seen as urgent and large, especially in Africa where it threatened entire societies with collapse.

Addressing hunger came in at number two on the priority list, with food supplements being backed to stop diseases caused by iron, zinc, iodine and vitamin A deficiency. The micro-nutrients that could be provided were estimated to cost US$12 billion, with the benefits associated being immense.

Opening up world trade came in at number three, because it was considered by the economists to have little cost but extremely high benefits. It was, however, acknowledged to face political resistance.

Malaria treatment and control rated as the fourth-best opportunity with the use of chemically-treated bed nets being strongly backed.

The proposals to combat malaria were estimated to cost US$13 billion, and while the benefits were lower than those for HIV/AIDS, they were still extremely high compared to others.

Climate change proposals, such as the Kyoto Protocol, were rated at the bottom of the list.

The economists favoured more modest proposals, and said that Kyoto demanded high costs for benefits that were as yet difficult to estimate and hundreds of years away. They said, however, that climate change was not an issue that should be ignored.

Economists' top five

* Control of HIV/AIDS

* Target malnutrition through food supplements

* Trade liberalisation

* Malaria control

* Target malnutrition through developing new agricultural technologies appropriate for poor countries