The world's richest man Bill Gates has donated $168m to fund research into malaria, the mosquito-borne disease which kills around one million people a year.
Mr Gates made the announcement as he toured a treatment and research centre in rural Mozambique with his wife Melinda.
The Gates' are in Africa to visit projects funded by their foundation
"Malaria is robbing Africa of its people and potential," the Microsoft chairman said.
"Beyond the extraordinary human toll, Malaria is one of the greatest barriers to Africa's economic growth, draining national health budgets and deepening poverty."
The parasitic disease, which is present in 90 countries and infects one in 10 of the world's population, is second only to tuberculosis in its impact on world health.
Mothers and children at risk
Ninety per cent of all malaria cases are in sub-Saharan Africa where it is the main cause of death and a major threat to child health, with 3,000 children dying a day from the illness.
Pregnant women are also particularly vulnerable to the disease, which is curable if diagnosed early.
The money from the Bill and Melinda Gates Foundation will be used to provide three research grants:
- One to develop a vaccine
- Another to use existing drugs to reduce the number of infections in babies
- And a third to develop new medicines to tackle drug resistant strains of the disease.
Medical experts say malaria accounts for 40% of public health spending in Africa and the new Gates grant will exceed the $100m currently allocated globally for research into the disease.
The BBC's Barnaby Phillips in Johannesburg says that, while the Aids pandemic has attracted most international attention, the threat of malaria has also been growing.
After years spent bringing the disease under control, the number of people dying from malaria is now higher than it was 30 years ago and has spread to new countries.
The increase in cases is due to a number of factors:
The disease is becoming resistant to traditional treatments.
Mosquitoes are developing resistance to the main insecticides which have been used to control the spread of the disease.
Political and social upheaval has led to large numbers of people moving into new areas where disease is spread more easily.
And changes to the environment, caused by road-building, mining and irrigation projects, have created a good breeding ground for malaria.
The Mozambique research centre that Mr Gates and his wife were visiting is in Manhica, a rural village 80 kilometres (50 miles) north of the capital Maputo.
The centre is said to be close to finding a new method for treating babies known as the "intermittent preventive treatment".
Malaria has been on the increase in recent decades
Early studies show that the administration of the anti-malaria drug sulfadoxine pirimetanine three times a day for the child's first year, could drastically reduce the number of infant sufferers.
Mr Gates, whose fortune was recently put at $46bn, is in Africa to visit projects funded by his charitable foundation.