While no case has been reported since Christmas Day, an intense series of tests is required before formal clearance can be given.
Queensland's Department of Primary Industries and Fisheries said three veterinary teams had arrived from NSW.
Chief veterinary officer Dr Ron Glanville said a total of 1080 randomly selected properties are being sampled throughout the amber and red zones in a move aimed at accelerating zone changes. These zone changes will allow freer movement of horses and help get things back to normal for horse owners.
"The surveillance team has a huge job to do over the coming weeks and we're very appreciative of those interstate veterinarians and horse handlers who have offered their time and assistance," Dr Glanville said.
"We also thank horse owners for their co-operation."
Each team from NSW consists of a veterinarian and a veterinary assistant. They will be conducting sampling within the amber zone.
"The department has also had recent assistance from veterinarians and animal health officers from Victoria, Western Australia and South Australia, and I extend my thanks to those states."
Horse owners are still being encouraged to report suspect cases. To date, all health problems identified in the horses in question had not been caused by flu.
"The more surveillance that has been undertaken with negative results, the greater the confidence that eradication has been achieved," Dr Glanville says.
Queensland's green zone that covered most of the state reverted to a white zone on February 1, and further zone changes are expected soon. The goal is for all of Queensland to be a white zone - an uninfected state - by June 30.
In New South Wales, which has no known infected properties and has not had a fresh case since early in December, horse owners have been reminded that movement restrictions will remain in place until testing confirms the disease has been eradicated.
Chief veterinary officer Bruce Christie said zoning and movement records were vital safeguards in case isolated pockets of EI infection were to be discovered during the proof-of-freedom testing.
"Although there is no known infection in NSW, we have to be certain that the EI virus has burnt out," he says.
"Until testing confirms EI has gone, previous movement restrictions will remain in place. In the white and purple zones this means a travelling horse statement must be carried when horses are being moved.
"In the short term, documented proof of immunity is also required in the purple zone. Horses in the red and amber zones can only be moved under permit.
"We are hoping to ease most movement restrictions within the next month."
Mr Christie said police would increase their monitoring of horse movements in high-risk areas to ensure ongoing compliance with movement restrictions.