University of Nebraska–Lincoln researchers develop faster, safer DNA-based vaccine to reduce disease risk and improve outbreak response.
Researchers at the University of Nebraska–Lincoln (UNL) are advancing a next-generation swine influenza vaccine that could significantly improve disease control in hog operations while offering a faster way to respond to emerging virus strains.
The new approach uses cutting-edge DNA delivery technology rather than traditional methods that rely on whole or partial viruses. Early research suggests this innovation could reduce the risk of severe illness in pigs and strengthen the resilience of the livestock sector.
Addressing a known vaccine challenge
Swine influenza remains a persistent concern for pork producers, with economic impacts tied to reduced growth performance, increased treatment costs, and potential trade disruptions. While vaccination has long been a primary tool for managing the disease, it is not without limitations.
A recent UNL study identified a critical issue with some conventional vaccines. When pigs vaccinated with traditional formulations encounter a different influenza strain than the one included in the vaccine, they can experience a condition known as vaccine-associated enhanced respiratory disease (VAERD). Instead of protecting the animal, the vaccine may worsen symptoms, leading to increased lung damage and illness severity.
“If you perform the necropsy, you’re going to see more severe lung lesion,” said Hiep Vu, associate professor of animal science at UNL. “Sometimes the animal will have higher fever compared to the non-vaccinated animal that are exposed to the same strain of virus.”
This finding underscores the importance of improving vaccine design to ensure protection across a broader range of virus variants.
A new DNA-based approach
To overcome these challenges, Vu and his research team developed a novel vaccine using lipid nanoparticles—tiny fat-like particles that can deliver genetic material directly into cells.
Instead of introducing a virus or viral protein, the vaccine carries a single gene that instructs the pig’s muscle cells to produce a harmless influenza protein. This protein then triggers an immune response, preparing the animal to fight off infection without exposure to live or inactivated virus.
The study, accepted for publication in npj Vaccines, compared this DNA-based vaccine with a traditional protein-based vaccine using the same influenza antigen. The results were striking.
When exposed to a different flu strain:
- Pigs vaccinated with the conventional vaccine developed significant lung damage
- Pigs receiving the DNA-based vaccine showed little or no lung damage
These findings suggest the new platform could eliminate or greatly reduce the risk of VAERD while still providing effective immune protection.
Benefits for herd health and disease control
Although the vaccine does not completely stop virus transmission, researchers say it still offers meaningful advantages for herd management.
Vaccinated animals typically require greater exposure to become infected and may shed less virus over a shorter period. This can help slow the spread of disease within barns and reduce overall outbreak severity.
For producers, this translates into:
- Healthier animals
- Lower treatment and mortality rates
- Improved production efficiency
At the industry level, reducing the severity and spread of influenza could support more stable pork production and enhance biosecurity outcomes.
Rapid response to emerging strains
One of the most promising aspects of the technology is its speed.
Traditional vaccines often require months to develop because they rely on growing and processing virus material. In contrast, the new DNA-based platform uses only a genetic sequence, allowing researchers to design and produce updated vaccines much more quickly.
Vu estimates that a new version could be developed in about one month. This rapid turnaround is particularly important as influenza viruses mutate frequently and new strains emerge.
The ability to respond quickly could be critical during outbreaks involving highly pathogenic viruses, including strains such as H5N1 avian influenza, which continue to raise concern across multiple livestock sectors.
Broader applications and industry interest
The implications of this research extend beyond swine. Scientists are already testing the same vaccine platform in poultry, with future studies planned to evaluate protection against H5N1.
“If we have the vaccine working in multiple species, then we can respond faster because we do not have to develop anything from scratch again,” Vu said.
The technology has also attracted commercial attention. A patent application has been filed through NUtech Ventures, and discussions are underway with industry partners to scale production and reduce manufacturing costs.
If successfully commercialized, the platform could offer a flexible and cost-effective solution for managing animal diseases across species.
Importance for North American producers
The development is particularly relevant for major pork-producing regions. Nebraska alone is home to approximately 3.6 million hogs, highlighting the scale of potential impact.
North America is a very integrated pig processing environment. The innovation could provide another valuable tool to manage disease risk in an increasingly complex production environments between counties like the United States and Canada.
As global livestock industries face ongoing challenges from evolving pathogens, innovations like this DNA-based vaccine may play a key role in protecting herd health, improving biosecurity, and ensuring long-term sustainability.
Photo Credit: Pexels - Barbara Barbosa