Columns share an author’s personal perspective.
Q: I read that someone in a COVID-19 vaccine trial developed transverse myelitis. What is this?
A: Vaccines are intended to stimulate the patient’s immune system to protect them from the disease for which they are being vaccinated. There is always a concern that this could unintentionally cause a side effect from stimulating the body to attack normal body structures or functions; this is sometimes called “molecular mimicry,” where a small piece of a protein/component in the vaccine is similar to a piece of protein/component in a body tissue, so the body’s immune response to the vaccine cross-reacts with this body tissue, causing an autoimmunelike condition. For example, in 1976 an aggressive swine flu vaccination program was halted because there appeared to be an increase, albeit still a rare occurrence, of Guillain-Barre syndrome in people who had received the vaccine.
On the other hand, it is also possible…