In people who show the beginning signs of multiple sclerosis (MS), a vaccine used to prevent tuberculosis in other parts of the world might help prevent the disease.
The study involved 73 people who had a first episode that was suggestive of MS, like numbness, problems with balance or vision problems, and an MRI that showed signs of possible MS. Researchers administered one injection of a live vaccine called Bacille Calmette-Guérin, which is used in other countries to prevent tuberculosis, but is not used for that in the United States, to 33 study participants. The others received a placebo.
By the end of the study, 58 percent of the vaccinated people had not developed MS, compared to 30 percent of those who received the placebo. Researchers say the findings support the “hygiene hypothesis” that better sanitation and use of disinfectants and antibiotics may account for some of the increased rate of MS and other immune system diseases.