THE MALARIAL FEVERS 



milder attacks. Usually, recurring attacks take place about the 

 same time on the succeeding days. 



The anaemia of tertian fevers is more easily overcome than that 

 of quartan, and great exhaustion is only seen in old debilitated 

 subj ects. 



Two interesting points may be noticed — (i) anticipation of the 

 attacks; (2) retardation of the attacks. Anticipation of the attacks 

 means shortening of the apyrexial interval, so that they begin at 

 short intervals. Retardation means prolongation of the apyrexial 

 interval, and is generally due to the action of quinine, but may be 

 due to spontaneous weakening of the parasite. 



Irregular Subeontinuous Tertian Fevers. 



Irregularity may be brought about by parasites maturing at 

 different times on the same day, and thus producing an almost 

 continuous fever with exacerbations and remissions; but tertian 

 fever is rarely duplicated — that is to say, it rarely shows two 

 distinct attacks in one day. Prolongation of the attack produces 

 a fever resembling the subtertian, while in very chronic tertians 

 just the reverse may take place — viz., prolongation of the apyretic 

 intervals — so that fever appears at the end of seven, eight, fourteen, 

 or sixteen days. 



Mixed Infections. 



Irregularity may also be produced by mixed infections of Plas- 

 modium vivax with Plasmodium malaricB, or with Laverania malarice. 

 These mixed infections can only be recognized by the microscopical 

 examination of the blood. 



Chronic Tertian Malaria. 



See Chronic Malaria, p. 1182. 



IV. THE SUBTERTIAN FEVERS. 



Synonyms. — Tropical malaria, Summer -autumnal fever, Malignant 

 tertian. 



Definition. — Subtertian malarial fevers depend for their symptoms 

 and course upon the life-history of Laverania malaricB, introduced 

 into the blood of man by an anopheline mosquito. 



Remarks. — Their clinical symptoms may approximate to the 

 type described for the other two malarial fevers when Laverania 

 malaricB lives mainly in the spleen and in the peripheral blood, but 

 more generally the symptoms of these fevers are very different from 

 those produced by the tertian parasites. The essential difference 

 is that Laverania malar ice can, and does, live largely in the internal 

 organs, and may even concentrate its forces upon one organ. As 

 clinical symptoms are produced by the derangement of the functions 

 of the organs and systems of the body, so the symptoms of these 

 types of subtertian fever may point to a given organ or to a given 



