"Brief and sudden illness"???

[PCIntern]

67. I normally analyze language and word usage

But many individuals are not aware of the distinction among descriptors so whoever composed the press release may have done so, unknowingly confusing illness with episode or condition.

It may well have been a blood clot. The exact same thing happened to the wife of a patient of mine who flew back from Israel. She dropped dead two days later, never having been sick.