HMM: FDA adds warning to J&J COVID-19 vaccine over links to rare autoimmune disorder. “The U.S. Food and Drug Administration announced a new warning for the Johnson & Johnson COVID-19 vaccine over its association with an increased risk of Guillain-Barre syndrome, a rare autoimmune disorder where the immune system damages the nerve cells.”

This is a well-known (though generally rare) side effect of many vaccines. The rushed Swine Flu vaccine of the 1970s had a higher rate than most, if I recall correctly. And, doing the search, it turns out that I do remember correctly, though the rate was still low: “The vaccine caused roughly one extra case of Guillain-Barré for every 100,000 people vaccinated. The seasonal flu shot is associated with roughly one to two additional cases for every 1 million vaccines administered.”