MADRID, Spain (AFP) - A Spanish health worker who was the first person to catch Ebola outside of Africa no longer has the virus, according to medical test results on Sunday, the government said.

Teresa Romero, who was hospitalised on October 6 at the Carlos III Hospital in Madrid, has tested negative for the deadly virus, the special committee responsible for monitoring the virus in Spain said in a statement.

She will be given another test "in the coming hours", said the statement, adding that her "health was... developing favourably".

Romero on October 6 became the first person known to have become infected with the haemorrhaged fever outside Africa, where it has killed more than 4,500 people.

The 44-year-old nurse caught the deadly virus after caring for two infected missionaries who were repatriated from west Africa, and who died shortly after arriving in Spain.

Fifteen people who had contact with Romero before she was diagnosed with Ebola, including her husband, have not yet shown any symptoms but are still being kept under observation in the hospital, said the statement.

The virus has a 21-day incubation period.