There are two ways for damage to occur.

One is a direct assault, by the organism or toxin.

The second is that the body mounts an immune response to
the infectious attack, and when the infection is gone, the antibodies remain, and contain DNA strands similar to nerve tissue and then attack it. It stops when the antibodies are removed finally and/or no longer made. This happens in some people with Strep, for example...develop Tourette's, called PANDAs. It is only one example, and doctors believe it could happen with other bacteria and/or viruses.

A third way is when inflammatory chemicals called cytokines, are formed in too great an amount, and these inflame nerves and joints and other tissues. A cytokine "storm" often follows some vaccines. And this is what your pertussis vaccine could be a culprit for.