Dr Hugh Millar said it was timely to remind people of the costly sacrifices and hours spent across the state to keep Victoria free of the disease, allowing racing to continue.
"Keeping Victoria EI free has taken a tremendous amount of work by Department of Primary Industies staff, the racing industry and the non-racing horse community," Dr Millar said.
"More than 70 people continue to provide 24 hour border security, which includes security staff and DPI roving field officers.
"In addition, there are on average 25 employees at the EI state disease headquarters, working seven days a week, managing areas such as permits, potential border breaches, EI testing and industry liaising."
Since late August, DPI has actively participated in the national decision-making process as part of eradication and containment efforts.
Dr Millar said DPI vets and animal health officers were also carrying out considerable field work.
"Keeping Victoria EI free has been our priority since the outbreak in NSW and Queensland and this has only been possible with the cooperation and support of the non-racing industry in Victoria," Dr Millar said.
"Work to ensure we remain EI free continues and includes activities such as the installation of covert cameras at border crossings to boost surveillance by security staff.
"We recognise there is still a long way to go and having come this far, we cannot afford to become complacent.
"Vigilance and cooperation by the community is still the key to keeping EI out of Victoria." last week at Darkes Forest and Helensburgh.
Four properties at Darkes Forest and three at nearby Helenshurgh tested positive to the disease.
"The number of infected premises had not significantly increased by yesterday, with infection spreading to just two more neighbouring properties in each district," said NSW deputy chief veterinary officer Ian Roth said.
"Given the high density of horses in the area, this is a sign that our rapid response has helped limit the spread of the extremely contagious EI virus.
"As soon as we identified suspect infections quarantine measures were introduced and when EI was confirmed the area was immediately moved from the amber zone to the red zone to further limit horse movements and introduce mandatory biosecurity and hygiene requirements.
"The infections are within the boundaries of a planned vaccination buffer around the nearby red zone, so vaccination of uninfected horses in the area was fast-tracked and the buffer extended."
Mr Roth thanked locals for their efforts in helping contain the disease.
"The only sure ways to contain this highly contagious disease are to stop other people having any contact with your horses and to shower and change into clean clothes before and after any contact with horses or horse equipment," he said.
"Keeping horses away from boundary fences will reduce the chances of infected horses passing the virus on to their neighbours and remove the patting temptation for passers-by."