Bird flu is changing fast and could become more dangerous to humans, new research from the University of North Carolina at Charlotte suggests.

A team of scientists found that the H5N1 virus, also known as bird flu, is becoming more adept at infecting mammals.

That includes cows and, to date, at least 64 people, according to the U.S. Centers for Disease Control and Prevention (CDC). As the virus keeps changing, experts worry it could spread more easily to humans.

“An H5N1 vaccine made (for an earlier strain) will have less efficacy,” said lead author Colby Ford in a news release. He's a visiting scholar at UNC Charlotte's Center for Computational Intelligence to Predict Health and Environmental Risks (CIPHER).

Co-author Dan Janies, CIPHER co-director, said large amounts of data can be quickly analyzed using artficial intelligence "to assess our preparedness for important problems such as H5N1, which is spreading rapidly to new hosts and regions including American cattle and farmworkers.” 

The team found that newer strains of the virus are getting better at avoiding the immune system, which could make past infections or vaccines less protective.

Bird flu is already considered a pandemic among animals. It has infected hundreds of bird species and small mammals. 

Now, it’s showing up in larger mammals like cattle. 

That shift makes it more likely the virus could spread to people, the scientists say.

The study was recently published in the journal eBioMedicine. Another paper, still undergoing peer-review, shows that a key gene in the virus has changed. This gene helps the virus get inside mammal cells and dodge immune defenses.

Speed is key when studying fast-changing viruses.

“In this study, our aim is to be more forward-looking to predict the potential health impacts of H5N1 influenza before a major event catches us off guard,” Janies said.

Using tools built during the pandemic, the team studied more than 1,800 virus-antibody interactions. They focused on H5N1's hemagglutinin (HA) proteins -- the part of the virus that helps it enter cells. 

Their findings show the virus is spreading quickly to dodge immune responses.

“High-performance computational modeling is a pathway for chipping away at multiple angles of biological variation at speed and scale,” Janies concluded. “It helps us tune our intuition to the right approaches for vaccine efficacy and infection control as viruses evolve.”