Page:Tropical Diseases.djvu/98

66 they generally tend to increase in number during a few days. They may persist, though after a time in decreasing numbers, in the circulation for one, two, three, or even six weeks after the small fever-causing intracorpuscular parasites and their associated fever have disappeared, whether spontaneously or in consequence of the administration of quinine. Although, when given early in an infection, quinine may prevent the appearance of crescents, yet, when they are once formed, the drug has apparently no influence on these bodies nor on their capacity for emitting microgametes. The crescent body does not cause fever; its presence is usually associated with marked cachexia.

It is a singular fact that in many of the worst types of tropical malaria as that of tropical Africa——crescents are few in number, and in some instances cannot by ordinary examination be found. A. Plehn states that during a period of two years in Africa he only once saw the flagellated body. On the other hand, when we meet with these African infections in England, crescents are frequently encountered, and often in great abundance; at all events, this is my experience.

Characters of the fever.—— It is found that the fevers produced by the malignant parasites are apt to be very irregular in their course. The rigor stage is relatively less marked; the pyrexial stage is more prolonged, and is often characterized by a tendency to adynamic conditions, together with vomiting, intestinal catarrh, pains in the limbs, anorexia, severe headache, and depression. After apparent recovery from the fever there is a great proneness to relapse at more or less definite intervals of from eight to fourteen days. Such fevers are accompanied by rapid destruction of corpuscles, and are usually followed by marked cachexia. At any time in their course symptoms of the gravest character may declare themselves.

The quotidian infections are comparatively rare; at all events, they have not been very frequently