An immunology expert says developing an effective Japanese encephalitis virus (JEV) vaccine for the pig industry could provide greater protection for the wider community.
Victoria’s Health Department is urging people in high-risk areas and industries to get vaccinated against JEV, after the mosquito-borne virus was detected in northern Victoria for the first time this season.
However, no such vaccine has been registered to protect pigs from the virus.
Professor Jason Mackenzie, from the Peter Doherty Institute for Infection and Immunity, said JEV was an issue for more than just primary producers.
Professor Jason Mackenzie says the goal is to stop transmission. (Supplied: The Doherty Institute)
“If we can stop the infection in the animal population, we can also try and reduce the impact the virus has within our communities and within our environments, to stop that transmission,” he said.
Australia experienced an outbreak of JEV in domestic pigs in 2022, with detections in more than 80 piggeries in Queensland, New South Wales, Victoria and South Australia.
Seven people died during that outbreak.
Two cases of JEV have been recorded in humans this summer in Victoria and Queensland, and the virus was also recorded in mosquitoes in multiple states.
One of the vaccines has been tested at six farms. (ABC Rural: Angus Mackintosh)
The federal government has confirmed it is aware of at least two pig JEV vaccines being developed in Australia.
The makers of two of these vaccines, along with the pig industry’s peak body, want to speed up the regulatory process and get the vaccine approved as soon as possible.
Gruesome reality
Victorian Farmers Federation pig group president David Wright saw firsthand the devastation JEV could cause in pigs.
His farm was one of the 23 Victorian piggeries impacted by the 2022 outbreak.
“It affects the sows and the newborn piglets — they go over term and your piglets are, unfortunately, born dead,” Mr Wright said.
“That has a massive impact on production, and staff, and the whole wellbeing of the piggery.”
Apiam Animal Health’s ACE Laboratory Services is one of two companies developing a vaccine for pigs in Australia.
The laboratory has already made thousands of doses of the research vaccine. (ABC Rural: Emma D’Agostino)
The company’s managing director Chris Richards is pushing for an emergency permit to trial his vaccine at more piggeries.
His vaccine has been trialled at six farms so far, but Mr Richards said he has 89,000 additional doses of the trial vaccine ready to be shared far and wide, permission pending.
“Those 89,000 doses could vaccinate every sow in Victoria over the next four weeks,” he said.
Researchers are hoping to get a permit for emergency use of the vaccine. (ABC Rural: Emma D’Agostino)
University of Queensland researchers are also looking for emergency powers to trial their vaccine at more locations.
Associate Professor Jody Peters said the university was waiting on regulatory approvals to further progress testing.
“I would love for a vaccine to be available to our farmers at the end of this mosquito season,” Dr Peters said.
Jody Peters (right) looks at cells used for vaccines with Jessica Harrison. (Supplied: University of Queensland)
Australian Pig Veterinarians Group president Sandy Adsett said she supported the development of a safe and effective vaccine.
“Given the devastating effects … and the difficulty in detecting its presence until the virus manifests in farrowing sows and their piglets, the Australian Pig Vets strongly supports the development and registration of any safe and effective vaccine candidate for use in pigs,” Dr Adsett said.
Regulatory process
The Australian Pesticides and Veterinary Medicines Authority (APVMA) is the Commonwealth agency responsible for managing such vaccines during the trial phase.
The authority has the power to issue emergency permits in circumstances that require immediate action to protect human health, the environment or trade.
APVMA would not comment on specific permit applications, but said its permits did not allow products to enter the market at a commercial scale.
Apiam Animal Health’s Dr Richards said countries such as New Zealand and the US allowed vaccines to be registered and sent to market within weeks.
Apiam Animal Health’s ACE Laboratory Services is making a pig vaccine. (ABC Rural: Emma D’Agostino)
The APVMA defended its processes, telling the ABC comparisons with other countries were not possible due to differing legislative requirements and environmental factors.
“The APVMA’s scientific evaluation of the safety and efficacy of veterinary vaccines is consistent with our global regulatory counterparts,” a spokesperson said.
An independent review of Australia’s pesticides and veterinary medicines regulatory system in 2021 found reform was long overdue and much needed.
Looking abroad
Australian Pork Limited chief executive Margo Andrae said she was working closely with government to try to fast-track the vaccine process.
The organisation is seeking permits for other products that could help protect pigs from JEV and manage mosquito populations, including a vaccine from Japan.
Margo Andrae says she is looking for options to protect pigs. (Supplied: Australian Pork Limited)
“Every opportunity to prevent something that causes harm to our animals, we will absolutely push for it,” Ms Andrae said.
She said the pig industry had hoped to have a homegrown animal vaccine by now, given the work researchers had been doing since the 2022 JEV outbreak.
But until then, it was imperative to “work together” to protect animal and human health.
“The best approach at the moment is making sure staff are accessing the human vaccines to keep them protected, covering up and controlling mosquitoes and, where possible, reducing water lying around your property.”
