Three large insurance databases showed sharp increases in cases of severe brain inflammation after the Covid mRNA shots, according to a new peer-reviewed paper.

People who received the Pfizer jab or booster had a 40 to 70 percent higher chance over the next six weeks of encephalitis or encephalomyelitis. The Moderna jab carried an even higher risk after the second primary dose or a booster.

Encephalitis is inflammation of the brain itself, while encephalomyelitis is inflammation of nerve sheaths in the brain or spinal cord. Both can range from relatively mild conditions to serious or even fatal illnesses. The researchers reported 47 cases following Pfizer’s jab; they did not disclose an exact figure for Moderna’s.

Though the finding was published in the peer-reviewed journal Vaccine, it has received little attention – in part because the authors presented the findings in a way that made them seem less statistically robust than they were.