University of Florida researchers are developing and testing Brucella vaccine varieties in cattle that will hopefully, in turn, help humans.
“The concept we are taking is, if we can eradicate this disease from livestock, we can eradicate the disease from humans,” said David Pascual, Ph.D., a professor of mucosal immunology at the University of Florida’s College of Veterinary Medicine. “If we eliminate the animal reservoir, we can help humans.”
People most commonly become infected with brucellosis, which causes flu-like symptoms and malaise, by eating or drinking unpasteurized dairy products, according to the Centers for Disease Control and Prevention. Cattle primarily become infected through nasal or oral exposure, as well as through sexual transmission, Dr. Pascual said.
“Brucellosis is a global disease,” he said. “This is not a disease with overt symptoms, yet it has been around as long as humans. New infections are occurring at a rate of about half a million people per year, which is believed to be nearly 25-fold underestimated.
“The outcomes of our various studies may give us some idea how the vaccines will work in humans.”
There is a vaccine for livestock already but it is only about 70 percent effective, even after revaccination, according to Pascual. There’s no brucellosis vaccine for humans.
Preliminary results from the team’s vaccine studies look promising, Pascual said.
“We hope to identify several vaccine candidates,” he said. “Then we will test each in cows to see if they’ll work.”
Because the primary routes of infection in both people and cows are oral and nasal, people put themselves at risk by eating non-pasteurized dairy products, according to the university. The vaccines are being developed as oral or nasal applications.