The US Department of Agriculture (USDA) has granted conditional approval for a vaccine to protect honey bees from American foulbrood (AFB), but it's how they administer it that has Australian researchers and beekeepers excited.
Developed by biotech company Dalan Animal Health, the vaccine contains dead whole cells of the Paenibacillus larvae bacteria, which causes AFB, and is expected to hit the US market this year.
The first of its kind, the vaccine is fed to worker bees that then incorporate it into the royal jelly they feed the queen, who passes the immunity on to her young.
While unlikely to prevent the destruction of hives in Australia, the method of inoculation could prove groundbreaking for some of the biggest threats the beekeeping industry faces.
What is American foulbrood?
Found in all Australian states and territories, AFB is a fatal disease caused by bacterial spores that cannot be cured, and by law all infected hives must be destroyed.
Australian Queen Bee Breeders Association president Richard Sims said that often meant burning or irradiation.
"One way or the other, the bees have to die," he said.
"If it gets into your breeders, you're in all sorts of trouble."
Spread by poor beekeeping practices or drifting adult bees, it infects the developing brood — the baby bees — killing them and leaving behind spores that can continue to cause disease for between 40 and 80 years.
"It's probably much like the flu for us — it's always there and it's just waiting for the right conditions to appear," Mr Sims said.
"It's one of those things you can't stop … there's nothing that can be done."
How do you vaccinate a bee?
Much like the flu in humans, without a cure the focus has been on prevention.
But unlike humans, bees cannot socially distance and until recently vaccination was not considered a viable option for insect immune systems, according to Emily Remnant from the University of Sydney.
"Normally, when you think about vaccination, you get delivered a piece of a pathogen and then your immune system produces antibodies and creates an immune memory," Dr Remnant said.
"But in insects they don't have antibodies … so having that immune memory, we're not really sure how it works in insects."
Dr Remnant, who studies how bees and viruses interact, said delivering a vaccine through the queen relied on a phenomenon called trans-generational immune priming – which researchers were only just starting to understand.
"It's where the offspring receive some kind of immune memory from their mother … in bees, it's via the egg yolk protein vitellogenin, which is one of the most abundant proteins in the honey bee ovary," she said.
"So when the queen lays eggs, she deposits a lot of these proteins into the eggs … it's thought they can bind to parts of the pathogens … and get deposited in the embryo.
"Any of the offspring from that queen that have these vitellogenin-pathogen combinations are effectively protected."
Prevention still the best protection
Dr Remnant said early studies showed vaccinated baby bees had improved survival rates, but it was not enough to eliminate the disease completely.
Given the protocol to destroy infected hives in Australia, she said that meant it was unlikely to have a lasting impact on AFB here, but it could help move research on other threats, like varroa mite, forward.
"The main excitement I have for this research is not necessarily the specific disease that they've been testing it against, but the potential that this could actually work for other diseases," she said.
Californian beekeeper and biologist Randy Oliver said the non-GMO vaccine suitable for use in organic production was a "logical step" away from antibiotic treatments.
"It obviously needs further field testing … [but it] could be of great benefit to our industry, with no risk to consumers," he said.
Queensland Beekeepers Association secretary Jo Martin said the industry faced multiple significant threats and would embrace science that led to healthier bees.
"We'll be watching with very close eyes any advancements within these trials and seeing how our colleagues in the US go with this exciting opportunity," she said.
"In the meantime, the best thing that the Australian public can do to support the beekeepers is buy Australian honey.
"That is going to keep the income generating and give them the ability to do their disease tests and maintain our really strong, beautiful bee populations."
Long way off Australian shores
The ABC asked Dalan Animal Health if it intended to make the vaccine available outside the US, but did not receive a response.
But when making the announcement, chief executive Annette Kleiser highlighted the global demand for disease prevention for pollinators.
"We are ready to change how we care for insects, impacting food production on a global scale," Dr Kleiser said.
A spokeswoman for the federal Department of Agriculture, Fisheries and Forestry said there were currently no vaccines registered or approved under permit for use in bees or other insects in Australia, and no applications were being assessed.
She said an import permit was required for all veterinary vaccines manufactured overseas, assessed by the Australian Pesticides and Veterinary Medicines Authority (APVMA).
A spokeswoman for the APVMA said how long that might take would depend on the complexity of the application and the type of permit sought.
