A new study shows that five years before their diagnosis, MS patients were statistically less likely to receive vaccinations than comparator groups. The researchers found no link between vaccinations and the development of MS.

Vaccinations are often mentioned as a possible risk factor for MS. Scientists from the Technical University of Munich and the Bavarian Association of Statutory Health Insurance Physicians analyzed a large KVB dataset representative of the general population. The data covered more than 200,000 individuals, including more than 12,000 MS patients. 

The researchers found that five years before being diagnosed, individuals who went on to develop MS had received fewer vaccinations than those who did not develop MS. This applied to all the vaccines investigated: those against pneumococci, meningococci, mumps, measles, rubella, chickenpox, human papilloma virus, hepatitis A and B, tick-borne encephalitis and influenza. The effect was particularly pronounced in the latter three cases: the control group had received significantly more vaccinations than the individuals who later developed MS.

The researchers said that given the large volume of data analyzed, they can conclusively state that there is no evidence that recent vaccination increases the likelihood of MS or the onset of an initial MS episode.

The study was published in Neurology, the medical journal of the American Academy of Neurology.