The new drug was developed by Manuel Patarroyo, director of the National Institute of Immunology at the National University in Bogota, Colombia, who passed on the rights to the prototype last May. It has already been tried in Latin America, proving effective against the most lethal form of malaria.
But, the WHO said, the Tanzania tests were 'much more serious'. Inhabitants in the region where they were carried out suffered about 100 times more mosquito bites than in Colombia, with up to 25 bites per night by infected mosquitoes.
Further tests are being carried out in Gambia and Thailand. Still more tests over the next two years could mean an effective vaccine in use by 1998, the WHO said. The cost of the new vaccine could be less than dollars 5 ( pounds 3.40) per injection.
Malaria affects two billion people, but 90 per cent of cases arise in Africa, where it results in up to three million deaths every year, a third of them among under-fives.
The disease is fought with insecticides and treated with drugs, but people who live in malaria-plagued regions cannot take the drugs continually because the parasites become resistant to medication.
Further detailed results of the tests on the prototype will be published in the British medical journal Vaccine on Friday.Reuse content