In Kikwit, 225 miles east of Kinshasa, the capital, at least 59 people have died of haemorrhagic fever possibly caused by the Ebola virus, according to the World Health Organisation (WHO) in Geneva. Mdecins Sans Frontires (MSF), the French aid agency, said doctors working in Musango, a second town, 190 miles from Kinshasa, also reported several patients with symptoms similar to those infected with Ebola. The agency said at least 10 people in Musango were infected with the disease, of whom three had died, probably as a result of coming into contact with a patient who had been evacuated from Kikwit.
MSF said its doctors had reported a total of 179 deaths in Kikwit a month after diagnosing the first cases of haemorrhagic fever. The Zairean authorities have since placed Kikwit, with a population of 600,000, under quarantine to contain the outbreak. Soldiers have set up road blocks and there is strict control over who enters and leaves hospitals and clinics.
Although the virus can be deadly, killing nine out of ten infected people, it is thought to be only transmitted by close contact with body fluids. Giorgio Torrigiani, director of the WHO's division of communicable diseases, played down the risk of the virus spreading widely.
''In spite of the very high mortality of Ebola disease," he said, "transmission of this virus does not occur easily and requires intimate contact with an infected person, such as close nursing contact, or with cont- aminated materials.''
The present outbreak, which the WHO said began in January, appears to be centred on a hospital where 10 medical staff, including two Italian nuns working as nurses, have died. Tissue samples from Zaire have been sent to the US Centers for Disease Control (CDC) in Atlanta for analysis.
A spokeswoman said that scientists would soon be able to confirm whether the mysterious disease is caused by Ebola. Peter Piot, a WHO scientist who helped to identify the Ebola virus when it first appeared in Zaire in 1976, said the present outbreak bears all the hallmarks of the virus, which causes fever, diarrhoea and bleeding from body orifices, and can kill within a week. A team of experts from France's Pasteur Institute, CDC in the US and the WHO has arrived in Zaire to investigate.
In addition to the 1976 outbreak, which killed 274 out of 300 infected people in Zaire, there was a second outbreak in 1979 that killed about 200 people in Sudan. A Swiss scientist working in the Ivory Coast con racted the virus last year after dissecting a monkey, but has since made a good recovery.
Ebola derives its name from a river in northern Zaire where the first known outbreak occurred, probably as a result of the virus jumping the ''species barrier'' from monkey to man.
More recently the virus has earned notoriety from the film Outbreak, starring Dustin Hoffman, which is based on a fictional epidemic in an American town.