Organon §233

Intermittent diseases in which constant disease states recur at fairly definite intervals may be either febrile or apparently non-febrile.

The typical intermittent diseases [point 1, above] are those in which an unvarying disease state returns at fairly definite intervals and recedes again at equally definite intervals. In between these outbreaks, the patient appears to be in good health. This disease pattern, where symptoms come and go at regular intervals, is found both in the apparently non-febrile intermittent diseases as well as in the febrile one: the many intermittent fevers.