A new study suggests that exposure to a toxin primarily found in sheep could be linked to the development of multiple sclerosis in humans. Researchers said that if the link between the toxin and MS is proven, this would suggest that vaccination would be an effective treatment for its prevention or in the early stages of the disease.

The study, carried out by the University of Exeter and MS Sciences Ltd., found that people with MS are more likely than other people to have antibodies against the epsilon toxin, suggesting they may have been exposed to the toxin at some time.

After reports of some MS patients in the U.S. having antibodies against epsilon toxin, the Exeter researchers tested UK patients for such antibodies. Using two different methods, 43 percent of MS patients were found to be positive for antibodies to epsilon toxin, in comparison to 16 percent of people in a control group.

The epsilon toxin, produced in the gut of livestock by the bacterium clostridium perfringens, damages the animal's brain and can kill them. While the toxin can also occur in the gut of other animals, and even in soil, it has mostly been studied as the cause of a type of blood poisoning in sheep. According to the researchers, while the epsilon toxin is known to be highly potent, no human vaccine has ever been developed.

The study was published in the Multiple Sclerosis Journal.