New vaccine developed for salmon disease

A vaccine has been developed to treat a virus that was responsible for a salmon mass mortality event in Southern Tasmania last summer.

The P. salmonis bacteria is still circulating in salmon pens, with the new vaccine produced by Tasmanian scientists at the Centre for Aquatic Animal Health and Vaccines at the Mt. Pleasant laboratories in Launceston.

Salmon Tasmania CEO John Whittington said it was a major breakthrough for the industry.

 “For the first time, we can vaccinate every salmon against the emerging endemic bacteria P.Salmonis,” Dr Whittington said.

“This means salmon will have a natural immune defence against the effects of the bacteria, which they weren’t able to have last summer. 

“While no vaccine is a silver bullet, this is a critically important new tool in our toolbox that industry has been developing as we prepare for the challenges that come with warmer waters over summertime.”

The Tasmanian salmon industry has collaborated for more than 30 years with the state and federal government to develop vaccines for aquaculture.

“Like every primary industry, the continued development of vaccines is critically important to salmon aquaculture, they improve fish health, reduce antibiotic use and enhance survival rates,” Dr Whittington said.

“This is part of industry’s ongoing commitment to investing in world-leading science that underpins our sustainable farming in Tasmanian waters.”

Dr Whittington said the vaccines made in Tasmania were tailor-made for the state’s industry.

“This model is the envy of the world, with Tasmania leading the way in terms of vaccine innovation in aquaculture. 

“We have the best scientists in the world working alongside industry to address the real-time and complex health needs of our salmon and that’s why our industry is the global leader that it is today.”

The state government has also submitted a fast-track application to the Australian Pesticides and Veterinary Medicines Authority to approve the antibiotic Florfenicol for the treatment of P.salmonis.

Tasmanian Greens Leader Rosalie Woodruff said that was not needed.

“The announcement today of a new effective vaccine to inoculate salmon is a further reason that an emergency permit to use the unregulated and untested antibiotic Florfenicol is totally unnecessary,” Dr Woodruff said.

“World's best practice would put the marine environment before company profits when responding to disease outbreak.

“This means destocking sea cages with disease before any other intervention such as use of antibiotics.

“Heavy use of antibiotics is widely recognised as a ticking time bomb for animal and human health globally via the emergence of antibiotic-resistant bacteria.”

Dr Woodruff urged the state government to immediately withdraw its support for Florfenicol and alter marine farming licenses to reduce the number of fish allowable in sea cages.