Subclinical Bordetello pertussis colonizes the nasopharynx (nose) in vaccinated people, but has long been thought to be harmless. The authors show that on the contrary, this is an important cause of multiple sclerosis.
Interestingly, the Bordatello pertussis (BP) and the BP toxin have been used for more than 50 years as adjuvants to induce autoimmune encephalomyelitis (EAE). EAE is the animal model for multiple sclerosis, and has been described in thousands of research papers since the 1960s. The authors propose that these adjuvants actually cause multiple sclerosis in humans, not just the animal model. They describe in detail the interaction between BP exposure, vaccination coverage, and multiple sclerosis in various populations.