Page:Tropical Diseases.djvu/423

XXII] malarial, nor any of the other recognized forms of continued fever. There is no doubt that in warm climates, besides the known fevers, there are several, if not many, undifferentiated specific fevers. But the clinical group indicated by the term "typho-malarial " is not one of these. Typho-malarial fever is an ordinary typhoid occurring in a person who has been exposed to malarial influences, i.e. who has become infected with the malaria parasite.

It has already been pointed out that the malaria germ may remain dormant for months or even years in the body, and then, on the occurrence of severe physiological strain— such as a chill, shock, excessive fatigue, and so forth— wake up again, and once more multiply and flourish in the blood and give rise to the phenomena of malarial fever. It is a recognized clinical fact, one familiar to our predecessors and much insisted on by them, that any disease process occurring in a person who has once had malarial fever is prone to take on an intermittent or periodic character; as if the previous malarial infection had left a sort of impress of periodicity on the constitution. Doubtless this is owing to the fact that in individuals with Laveran's parasite dormant in their tissues the physiological strain implied by the presence of active disease paralyses for the time being the innate protective power of the human body, and the parasite is once more permitted to multiply and work its mischief in the blood. There are few more depressing influences than typhoid. Little wonder, then, that typhoid in a malarial is often accompanied by clinical evidences of a resuscitation of the malaria germ. And so it comes to pass that an attack of typhoid in malarial countries, or in persons returned from malarial countries, is prone to assume some of the characters of intermittent or remittent fever.

Not infrequently, instead of the slowly increasing headache, malaise, creeping cold, anorexia, and day-by-day ladder-like rise of temperature, the first recognized sign of typhoid in such circumstances is a violent rigor, immediately followed by rapid rise of temperature,