We have already mentioned (p. 262), in describing the general symptoms of pernicious infections, that vomiting, diarrhea, epigastric pain, and icterus were frequent occurrences. When these symptoms become conspicuous, we speak of a bilious remittent fever. This form becomes pernicious only on the occurrence of special complications.
In addition to this form we differentiate, since Torti's time, several others associated with prominent participation of the digestive tract, which become threatening through the occurrence of algid symptoms. These frequently take on the mask of other infectious diseases affecting the intestine.
These gastro intestinal pernicious fevers are endemic, especially in the tropics, and we owe the majority of our modern descriptions to French or English marine or military physicians, who had the opportunity of studying them in the colonies.
They occur also in southern malarial regions, as Algeria, Italy, etc., but less frequently, and are there usually characterized by less severe symptoms. In past centuries they were more common in these regions, as is proved by Torti's communication, in which they are given considerable space.
The diagnosis was extremely difficult, especially in countries like India, where other intestinal diseases, as cholera and dysentery, are endemic. This difficulty of diagnosis was so great that entire epidemics or endemics sometimes passed without the physician being able to agree whether they were this, that, or the other disease. It is to be hoped that now, with the general spread of the knowledge of malarial parasites, this confusion of the tropical fevers will be rapidly cleared up.