It was reported[1] that these were not random embassy staff members: > The first four Americans to report being struck by the phenomenon — including the fit-lo

It was reported[1] that these were not random embassy staff members: > The first four Americans to report being struck by the phenomenon — including the fit-looking man in his 30s — were all CIA officers working under diplomatic cover, as were two others affected later on. Ignoring the terrible operational security in effectively leaking the identities of intelligence officers, this could point out a more mundane explanation - an occupational injury, maybe as a result of operating specific equipment. [1] https://www.propublica.org/article/diplomats-in-cuba https://www.propublica.org/article/diplomats-in-cuba