DRESSED in a pair of baggy trousers, the world’s richest man looked out of place sitting on the floor of the Manhica research centre, 50 miles (80km) north of Maputo, among some of the world’s poorest people.

Surrounded by impoverished mothers and infants sickened by malaria, Bill Gates yesterday gave $168 million (£103 million) for research into malaria, the largest-ever gift by a single individual to combat the killer disease.

Most of the money will go towards accelerating research into 15 possible vaccines, widely regarded as the silver bullet of anti-malaria research.

But for Mr Gates, the Microsoft tycoon whose sprawling software empire brought him a personal fortune of $43 billion, this gesture is simply part of a greater goal. America’s richest man has declared that before his death he will give it all away to improve the health of the four billion people living on less than a dollar a day.

Following in the footsteps of the great 19th-century philanthropists, John Pierpont Morgan and Andrew Carnegie, Mr Gates and his wife, Melinda, have set themselves the goal of bridging the health gap between the First World and the Third World. This has left children in poor countries ten times more likely to die from illness than their counterparts in the developed world. Endowed with $25 billion, the Bill and Melinda Gates Foundation is now the largest charitable trust in the world. Set up in 1996 after the birth of their first child, already it has donated more than $3.2 billion to help fight HIV/Aids, tuberculosis and malaria — more than the entire research and development budget for health on the African continent.

“Malaria, along with Aids, is one of the two most challenging diseases,” Mr Gates said. “Malaria kills more than one million people a year and it’s a disease that’s getting worse because malaria strains are now resistant to inexpensive drugs, like chloroquine, that have been able to provide treatment in the past.

“A lot is riding on the outcome of this research. Malaria is the leading cause of hospitalisation and death for children here in Mozambique, and we’re losing ground — the number of infant deaths in eastern and southern Africa has doubled over the past two decades.”

In fact, the situation is far worse than Mr Gates described. Malaria, a parasitic disease transmitted by the female Anopheles mosquito that destroys red blood cells and impairs blood flow to vital organs, was pushed back to the margins in the 20th century, but now is making a terrible comeback. Last year, up to 900 million people were infected by malaria, according to estimates by the US Agency for International Development. Of that number, more than one million — 2.7 million by some estimates — died. The vast majority were in Africa.

Malaria’s resistance to chloroquine is so widespread that the drug is now utterly ineffective in up to 80 per cent of cases. In rural hospitals all over Africa, children lie three or four to a bed, sweating, shivering, severely anaemic or comatose from the disease. It is one of the most horrific sights on the continent and the disease is now estimated to be killing 3,000 children a day.

Yet the rich nations of the West have forgotten it. Of the $70 billion spent each year by rich countries on research and development into new drugs, only about 10 per cent goes on diseases affecting poor countries, even though they account for 90 per cent of all illness and death in the world. Nevertheless, international efforts to contain or even eradicate the disease have received a boost in recent years with large grants from the United States and from the $4.7 billion five-year United Nations Global Fund for Aids, Tuberculosis and Malaria.

Mozambique — one of the world’s poorest countries — is also one of the nations worst-hit by malaria.

Dr Clara Menendez, who was supervising trials on 2,000 children to test the new vaccine, said: “It has been a struggle to get funds, so this is very positive and very welcome.”

Mr Gates said: “We made the decision that our wealth will go back into society, but problems like malaria are of such a scale that no one person can solve them. These diseases can be defeated. Philanthropy can help, but governments in the developed world must play their part.”

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