Research into how horses manage to naturally eliminate a liver virus related to the hepatitis C virus from their system has the potential to ultimately benefit humans, according to researchers.
Equine hepacivirus (EHCV) is the closest known relative to hepatitis C virus.
The hepatitis C virus causes a blood-borne infectious liver disease affecting an estimated 2.7 to 3.9 million people in the United States, according to the Centers for Disease Control and Prevention.
Until recently, few cases of EHCV infection had been reported in horses because the virus cannot be detected without blood work. Also, horses are often capable of eliminating the virus on their own. The ability of horses to do this is an impressive feat and the secret to their strong immune systems could help prevent the disease in humans.
“We have a unique opportunity,” said professor Robert Mealey, an equine veterinarian in Washington State University’s Department of Veterinary Microbiology and Pathology.
“If we can learn how the horse’s immune system eliminates the virus, we might be able to apply that knowledge to finding a hepatitis C vaccine,” he told the university’s student publication, The Daily Evergreen.
Mealey and his collaborators were recently awarded a grant by the National Institute of Allergy and Infectious Diseases to pursue this research.
Prior research on the hepatitis C virus examined chimpanzees because of their biological similarities to humans. But now that chimps are an endangered species, alternative research methods are needed.
Though there are many biological differences between humans and horses, researchers believe studying a virus in horses could yield applications for human treatment of hepatitis C.
Natural EHCV infection appears to be relatively common, with up to 40 percent of horses showing signs of infection in some published studies. However, the virus does not result in recognizable primary signs most of the time.
“Horses don’t get sick like humans with HCV do,” said Charles Powell, public information officer for the College of Veterinary Medicine. “They won’t be fazed like you or I, but research will help identify illness better and help them recover.”
Mealey agrees that EHCV research will probably help horses in recovery sooner than it will yield results for preventing hepatitis C infection in humans, but he considers progress for either to be a success.
“These things go both ways,” Mealey said. “Keeping our animals healthy will keep us healthy too, and vice versa.
“If we can learn how the horse’s immune system eliminates the virus, we might be able to apply that knowledge to finding a hepatitis C vaccine.”