A new type of arenavirus has been identified as the cause of the deaths of four people since last month, specialists at the National Institute for Communicable Diseases (NICD) in Johannesburg said yesterday.

A new type of arenavirus has been identified as the cause of the deaths of four people since last month, specialists at the National Institute for Communicable Diseases (NICD) in Johannesburg said yesterday.

"There is no doubt we are dealing with a newly emerged virus," said Janusz Paweska, head of the special pathology unit at the NICD.

Until two weeks ago they did not know they were dealing with a new virus. The first person known to have died from the virus was Cecilia van Deventer who was flown from Zambia to South Africa last month for emergency treatment. Since then the paramedic who accompanied her, Hannes Elf, a nurse at the Morningside Medi Clinic, Gladys Mthembu, and contract cleaner, Maria Mokobung, have died. Another nursing sister is receiving treatment after showing symptoms.

Professor Adriano Duse, clinical microbiologist of infectious diseases at the National Health Laboratory Services, said of the work leading up to the "eureka moment" of trying to identify the virus: "It was quite scary, draining and involved long hours of work."

The NICD worked with a network of specialists globally, and the virus was identified by them and a laboratory in Atlanta in the US.

Professor Robert Swanepoel, a consultant for the specialist pathogens unit, said they would have to settle on a name which did not create negative connotations for the area from which the first patients came. Viruses are named after the area the first patients are known to originate from.

Swanepoel said they didn't want to wipe out tourism in an area or create fearful associations. - Sapa