Athens, Georgia, U.S.A.-based animal research company Dalan Animal Health has made a major breakthrough in shrimp immunity that it says could revolutionize the aquaculture industry.
Shrimp were previously considered impossible to vaccinate against common diseases, because they possess only a rudimentary immune system. Unlike the human immune system, shrimp only possess an “innate” immune system, which always responds to all pathogens similarly instead of adapting to new threats.
Scientists had long believed it was impossible to use vaccinations on animals who only have innate immune systems, because their immune responses could not learn to recognize new pathogens. Dalan said it has proved otherwise, showing that targeted vaccination of female animals with innate immune systems can pass immunity onto their offspring.
"For decades, disease prevention has focused on the adaptive immune system. We are changing that paradigm," Dalan Animal Health CEO Dr. Annette Kleiser said in a company release. "Our research proves that innate immunity can be trained, offering a revolutionary new way to protect animals, ecosystems, and the global food supply."
The breakthrough all started with honeybees. Dalial Freitak, one of the company’s founders and its Chief Scientific Officer, was working at the University of Graz, in Austria, when her research showed that though honeybees lacked an innate immune system, they had a specific immune-priming protein. She hypothesized that this immune-priming mechanism could allow them to be vaccinated, and proposed an experiment to attempt a prenatal vaccination. This was achieved through feeding an inactive version of a bacteria to a colony queen, who then distributed the vaccine in her eggs.
“I stumbled across [Freitak’s] idea in 2018,” Kleiser, a scientist and biotech entrepreneur, told SeafoodSource. At the time, Kleiser was working for the University of Helsinki in Finland, helping to assess startups that might be suitable for commercialization.
“I was like, somebody needs to do this. This is amazing,” Kleiser said of Freitack’s hypothesis that honeybees could be prenatally vaccinated. “I decided to start the company myself and get it off the ground.”
The approach used in Freitak’s research is essentially a traditional approach to vaccination, Kleiser said.
“You take the pathogen that causes the disease, in our case it was a bacterial disease that affects honeybees around the world. We took a high sample from the infected hive, grew up the bacteria inactivated, and then we fed it to the queen bee,” Kleiser said. “Then, the queen passes the vaccine into her ovaries, where the developing larvae, the next generation, will be exposed to a piece of this dead bug and start mounting an immune response, which will then protect them once they hatch.”
The honeybee vaccine tests were successful at protecting colonies from American Foulbrood, a disease which has decimated honeybee populations worldwide, and the company received conditional regulatory approval from the USDA to use the new technique in 2023. Kleiser said the new vaccine is the same as any livestock vaccine, and regulated as such.
“We know that vaccines are extremely effective in preventing and containing the spread of diseases, and [bees] are extremely important to our survival, to our food security,” she said. “It’s not just a feel good issue, because we all like bees. They’re really critical for feeding the world.”
Dalan Animal Health has so far dosed over 30,000 colonies in the U.S. and Canada with its vaccine.
Following their successful honeybee vaccine, Freitak and Kleiser hypothesized the same mechanism of maternal genetic transfer would exist in shrimp, and they started testing vaccines on female shrimp broodstock. Kleiser said they were unprepared for the striking positive results of their experiments.
Dalan’s proof of concept trials of their shrimp vaccine showed more than 60-percent protection from White Spot Syndrome Virus (WSSV) and Early Mortality Syndrome (EMS), two of the shrimp industry’s most pressing threats. Once Dalan’s shrimp vaccine is fully developed and commercialized, it has the potential to protect shrimp producers from diseases that regularly wipe out harvests and which have spread quickly around the world.
The company has already begun this process.
“We have one strain that we like particularly well, that we want to take forward into development and get this vaccine to farmers,” Kleiser said.
A major difference between Dalan’s product and that of its competitors, Kleiser said, is that it is far more biosecure, and environmentally sustainable.
“We don’t have to go into the pond, so you don’t expose your pond to the vaccine. It’s literally just the broodstock. It’s a very effective way to do this,” she said
Kleiser said that other companies which have tested vaccines on shrimp ponds have faced regulatory challenges due to the nature of the application.
“It’s always a question of how much [of the vaccine] did [the shrimp] eat? How much did they consume? Those concerns are not there [with this product] from a regulatory perspective,” she said.
A safe vaccine for shrimp could revolutionize the shrimp industry. Currently, shrimp producers, feeling financial pressure to keep their shrimp healthy, often resort to the use of veterinary antibiotics to protect whole shrimp ponds. Though trace amounts of banned antibiotics are probably not dangerous for individual consumers, there are concerns that the widespread overuse of antibiotics in aquaculture could contribute to antibiotic-resistant pathogens, which the Global Seafood Alliance (GSA) says kill over 1 million people a year.
There is evidence that the use of antibiotics in shrimp farming is on the rise, too. In February 2025 the Southern Shrimp Alliance reported that the U.S. Food and Drug Administration (FDA) had refused more shipments of foreign shrimp for banned antibiotics in 2024 than in any year since 2016.
Kleiser said that another benefit of vaccinating broodstock, rather than a whole pond, is that the shrimp’s immune response is only stimulated once. Pond treatments can continually stimulate immune responses, creating costs in other areas, like how much food the shrimp eats or how quickly it grows.
“What the next generation needs is to be prepared in case a stimulus comes,” she emphasized. “But if the stimulus isn’t there, they don’t have to [respond]. So there’s no cost to the individual.”
Asked if she sees other applications for seafood, Kleiser said that she is interested in studying a vaccine to produce disease immunity in oysters.
“We can figure this out,” she said. “We’ve learned a lot in bees [in terms of] what works and what doesn’t work, how to make it work, how to manufacture it. And that has helped us with shrimp to get to positive data so quickly.”
