Atypical agues.—— Cases are frequently met with in which all the above symptoms are very much toned down; in which, perhaps, a periodically recurring feeling of coldness, followed by languor, or a slight headache, or a slight rise of temperature, is the only symptom indicating the presence of the malaria parasite in the blood. In some fevers, and these by no means the least dangerous, the subjective symptoms may at first be of so mild a character that the patient is able to go about his duties with a body temperature of 103° or 104° F.; he may have no severe rigor, no headache, no severe gastric symptoms, no acute febrile distress of a disabling character. Some of the African fevers ——so liable to assume suddenly a pernicious character ——are of this nature. On the other hand, notwithstanding a comparatively slight rise of temperature, headache, prostration, or vomiting may be extremely distressing. There is an infinite variety in this respect. Evidently the toxin—— if toxin there be—— of the malaria parasites is far from being a simple body; probably, like tuberculin, it contains several ingredients arranged in different proportions in the several species and varieties of the parasite. Doubtless, also, the degree of infection, various combinations of the species of parasite, and individual idiosyncrasy play a part in determining the intensity and character of the reaction of the human body to the toxin.
Terms employed.—— Acute malarial attacks which recur daily are called quotidian ague; if they recur every second day, they are called tertian ague; if every third day, they are called quartan ague. As a rule, the attacks tend to occur about the same time every day. In some cases the time of recurrence becomes earlier each day; such fevers are said to anticipate. Or they may occur at a later hour; in which case they are said to postpone. When the individual paroxysms are prolonged, so that one attack has not concluded before the next commences, the fever fits are said to be subintrant. When the fit is prolonged and periodicity is marked by only a slight fall of temperature, a slight sweating, a
