jet vapour trails.... well that certainly fits in with the problems documented in 1690.

is it possible that the psychosis is biological as part of a real parasitic infestation?

Porphyria which is not considered parasitic evidences some of the same symptoms including lesions, unusual hair growth, sensations of itching crawling skin as well as paranoia, hallucinations, etc.

Current medicine still has a problem with treating people as a whole organism. Too easy to just prescribe something for this or that symptom and ignore the big picture.