Organon §242

Psoric intermittent fevers may develop in untreated or poorly treated cases of epidemic fever. 

If the first attacks of such an epidemic intermittent fever are left uncured, or if the patient is debilitated by allopathic mistreatment, then the indwelling, dormant psora (which unfortunately is already in so many human beings) develops and takes on the typus of the epidemic intermittent fever; that is, the psoric disease, to all appearances, plays out the role of the epidemic intermittent fever. In these cases, the medicine that would have been helpful for the initial paroxysms is no longer fitting and can help no more. We now have a case of psoric intermittent fever only. It is usually vanquished by the subtlest doses of sulphur or hepar sulphuris in high potency.