It is only when a sufficient number of parasites sporulate simultaneously and pour out into the circulation sufficient toxic material to cause a well-marked paroxysm that such occurs—with less poison we may only have vague suggestions of an attack of ague.
In a large proportion of cases there are no prodromata, they begin with a sudden onset.
Malarial paroxysms show a preference for the forenoon or at any rate tend to occur in the early afternoon, rather than in the evening.
Mixed and Multiple Infections
When there are two generations of tertian parasites, each maturing on successive days, we have a paroxysm every day—a quotidian fever. Such a tertian infection is called a double tertian. In quartan infections, with the seventy-two-hour cycle of development, if we have two generations of parasites sporulating on succeeding days, but with an apyretic day intervening, we have a double quartan. If three generations of quartan parasites sporulate on three successive days we have a triple quartan infection. When two species of parasites are present in the same case we have a mixed infection. Mixed infections of malignant tertian and benign tertian are the most common, next, those of quartan and malignant tertian and very rarely those showing quartan and benign tertian. All three species have been found in a single individual.
Clinical Types
A Typical Benign Tertian or Quartan Paroxysm.—(Other than for the difference in periodicity the paroxysms of these two malarial infections are alike.)
The ague attack generally commences with malaise and slight headache, frequently accompanied by yawning and stretching. Chilly sensations radiating from the spinal column to the extremities and the jaws give way to actual chill with shaking body and chattering teeth, face pinched and bluish and cutis anserina.
The pulse is frequent, small and of rather high tension, there is increased frequency of urination and nausea and vomiting may be present.