THE issue of vaccinating horses against Hendra virus has again been raised after a case was confirmed west of Macksville.
A mare died suddenly on Wednesday after been seen earlier in the day appearing normal.
The property was immediately placed into quarantine where there is one other horse, three dogs and two cats on the property.
Three family members from the property and a vet were assessed for potential exposure to the virus but NSW Health reports none of the quartet had any exposure of concern.
NSW Chief Veterinary Officer Ian Roth said the disease response was part of DPI's biosecurity strategy aimed at safeguarding the State's primary industries, the environment and the community from biosecurity threats.
"This is the first Hendra case in NSW since 2011 when 10 horses died on eight properties between late June and late August," Mr Roth said.
"All properties affected in 2011 were in north eastern NSW, in the localities of Wollongbar, Macksville, Lismore, Mullumbimby and Ballina."
The Nambucca Valley property and those in the region have a large flying fox population and Mr Roth explained this a real issue.
"The Hendra virus is endemic in Australian flying fox populations. Flying foxes are the natural host for the virus," he said.
NSW continues to be on high alert for Hendra disease in horses, as there have been eight cases of Hendra in horses in Queensland in the last 12 months.
Steps have been taken to ensure another outbreak doesn't occur in NSW again.
"A total of 699 horses tested negative for Hendra in New South Wales since July 2012," Mr Roth said.
He added Hendra virus can spread from flying foxes to horses and, rarely, from horses to people.