Note:  Do not rely on this information. It is very old.

Jail fever

Jail fever. A term which is now happily out of date. In bygone days, when little or no attention was directed to the sanitary conditions of prisons, and when gross overcrowding was allowed to exist in them, it was no uncommon thing for large numbers of prisoners to die of a malady to which this name was given. The disease was probably, in most instances, typhus fever.