Aneurysm
An aneurysm was a medical condition that could affect Humans. They were known to occur sudden in people who might have appeared just fine shortly before. They were treatable, but might take a person out of commission for some time and require a sufferer to rest for a few days after. ()

In 2372, The Doctor searched for an aneurysm as one of several potential explanations for Captain Janeway's hallucinations. ()

In 2375, Admiral William Ross was found slumped over his desk while aboard the  while in orbit of Romulus for a conference. An aneurysm was suspected by Doctor Frame, and later confirmed. He made a full recovery. Julian Bashir later suggested to the admiral that the aneurysm was rather convenient, as it caused Bashir to lean on Cretak for assistance, thereby aiding a Section 31 plot. ()

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Medical conditions