He was Ben Cunneen, who was aged in his 30s.

Dr David Lovell, the owner of the clinic at the centre of the outbreak in which five horses have died, confirmed the death of Mr Cuneen to ABC Radio today.

"It is the thing we have been fearing, I guess, right from the start," he told radio listeners.

Dr Lovell said Dr Cunneen had been with the practice for a long time.

"He was the first person that became infected in this outbreak. He has been very, very seriously ill in hospital."

It is understood Dr Cunneen, who is married without children, died shortly after 7pm after being hospitalised for about five weeks. He has been in intensive care for the last few weeks.

A second staff member, a vet nurse, also contracted the virus and remains in hospital. Dr Lovell indicated her condition was better.

"I can't go into too many details. I think we have got some good news there. I think she is doing quite well."

The death had hit the family and work mates of Dr Cunneen hard, he said.

"It's just devastating," Dr Lovell said.

Dr Cunneen graduated as a vet from Sydney University and joined the Redlands clinic in the mid to late 90s. He returned to Sydney for a time before rejoining the clinic.

The Hendra virus was first identified in 1994 in an outbreak that killed racehorse trainer Vic Rail.

Authorities believe the Redlands outbreak resulted from a long-term resident horse at the clinic becoming infected by droppings or other matter being dropped from native bats who are known to visit trees at the clinic.

Last week, a $A200,000 racehorse who recovered from the virus was euthanized under biosecurity regulations to reduce the chance of further infection.

A vet involved in the euthanizing was admitted to hospital for observation after suffering an accidental needle-stick during the process.