Biosecurity Queensland Chief Veterinary Officer Dr Rick Symons said while the results were promising, these were just the first of three rounds of testing.
"These results were for the five horses on the property where a horse became infected with Hendra virus," he said.
"Yesterday samples were taken from all 20 horses on the second property at Biddaddaba where the infected horse was transported and later died, and the results are expected back in the next couple of days.
"All of the horses on both properties are under observation by Biosecurity Queensland staff in conjunction with the horse owners.
"However, we need to complete three negative rounds of testing on a property before the quarantine can be lifted. Typically this takes around 32 days."
Symons said apart from animals on the two affected properties, horses can be freely moved within and outside of the Beaudesert area.
"As for Hendra virus, it is present in flying fox [native bat] populations which can be transferred to horses, between horses, and from horses to humans. However the risk of horses being infected, and in turn humans, is very low.
"The few cases of Hendra virus infection in humans have been the result of very close contact with an infected horse's body fluids such as blood, nasal discharge, saliva, or urine.
"There is no evidence of human-to-human or flying fox-to-human spread of Hendra virus.
"Owners can help protect their horses by taking measures to keep them away from trees where there are flying foxes, keeping water containers under cover and feeding horses under cover."