As cases of Japanese encephalitis virus (JEV) spread in Australia, there are concerns the high cost of the vaccine is putting some people off getting the jab.
The vaccine currently costs $300, but a trial to administer it in smaller doses could see it used to protect four times as many people, and the cost slashed by up to a third.
JEV is transmitted by mosquitoes and has recently spread through Queensland to New South Wales, Victoria and South Australia, with 33 cases confirmed and three deaths.
Luis Furuya-Kanamori, a research fellow at the University of Queensland's Centre for Clinical Research, said preliminary results from the first 11 participants in the trial were promising.
"All our initial participants were protected against the virus after a month of receiving the vaccine," he said.
Smaller doses to reach more people
Dr Furuya-Kanamori said participants in the trial were given a smaller dose into the top layer of their skin, rather than into the muscle, an approach used successfully in rabies and yellow fever vaccination.
"We are keeping one fifth of the standard dose, so we can use the same vial and spread it through four participants," he said.
Dr Furuya-Kanamori said this could bring the cost down to about $80 per dose and increase the dose numbers in Australia, which had limited vaccines.
"I believe the federal government has purchased more than 100,000 vaccine doses, so it will be really important that people at risk are starting to get immunised," he said.
The vaccine is being prioritised for those deemed high-risk, including farm workers and their families, transport workers, veterinarians, pork abattoir workers, mosquito and virus researchers.
Dr Furuya-Kanamori said trial participants were followed for two months, with final results expected in the second half of this year.
The study currently has 30 participants and is looking to enrol another 20 from the Brisbane area.
Watching closely
Animals infected by JEV have also been confirmed in at least 50 piggeries across four states, a situation watched closely by central Queensland farmer Laurie Brosnan.
"We had a trial run with COVID-19, so the disease response unit within all levels of government has been very good," he said.
He and his team at Bettapork in Biloela have not been offered the vaccine yet because the limited supply meant those at highest risk were getting the jab first — and no cases of JEV had yet been recorded in the region.
Mr Brosnan welcomed the preliminary findings from the current vaccination trial.
"If it's going to bring down the cost of vaccine programs, [then] it's 100 per cent backed up by the industry," he said.
He considered JEV to be just another blow for an industry already struggling with high input costs and staff shortages in abattoirs.
"The first thing we did was roll our eyes and thought, 'Here we go again, something else'," Mr Brosnan said.
"But it's a massive concern, obviously, for our staff health and safety, as well as the welfare of our animals.
"We're by no means out of the woods or immune from it.
