THE INFECTION IN THE INTERMEDIATE HOST 
SYMPTOMATOLOGY, FALCIPARUM MALARIA 
By S. F. KITCHEN 
INTERNATIONAL HEALTH DIVISION, ROCKEFELLER FOUNDATION, TALLAHASSEE, FLA. 
Falciparum malaria is essentially, from 
a clinical standpoint, a very different dis¬ 
ease from P. vivax and quartan malaria. 
Among the reasons for this difference are 
certain fundamental characteristics prob¬ 
ably peculiar to the causative organism. 
These characteristics, by reason of which 
P. falciparum, malaria in particular of the 
three classical infections may be attended 
by great hazard and well deserves the term 
“malignant,” are: (a) Marked invasive¬ 
ness. Extraordinarily rapid and great in¬ 
creases in the numbers of parasites occur 
and the amount of debris and foreign pro¬ 
tein released into the circulation at spolia¬ 
tion time is thereby greatly increased. The 
toxicity of this species of plasmodium, per 
se, is probably not remarkable; in the 
writer’s opinion it is less than that of P. 
vivax or P. malariae at equivalent parasite 
densities, (b) Internal sporulation. As 
Marchiafava and Bignami (1894) noted 
almost half a century ago, “the fission of the 
amoebae is effected for the most part in the 
capillary system of certain of the viscera. ’ ’ 
Very large numbers of parasites are condu¬ 
cive to the blocking of capillaries, especially 
in view of the agglutinative trait of the 
parasitized erythrocytes that has been de¬ 
scribed, together with, a tendency for them 
to adhere to the vascular walls. Further¬ 
more, one or more organs may bear the 
brunt of this process. This explains the 
multiplicity of symptoms that will be noted 
later and justifies the term “malarial mim¬ 
icry,” used by Castellani and Chalmers 
(1919). (c ) Asynchronization. This para¬ 
site does not lend itself readily to regimen¬ 
tation of sporulation. As will be described 
subsequently, this is reflected in the irregu¬ 
larities of the febrile reaction exhibited by 
the host. 
Prodromal symptoms. Usually in typical 
primary attacks in wholly susceptible per¬ 
sons the patient will complain for 2 or 3 
days prior to the onset of paroxysms of gen¬ 
eral malaise, loss of appetite, perhaps a 
vague feeling of ill-being or exceptional 
fatigue and localized aching. The tempera¬ 
ture during this time may or may not show 
slight daily elevations, and chilly sensa¬ 
tions may be experienced. Prodromal 
symptoms, however, may be almost negli¬ 
gible or entirely wanting, and the onset may 
be abrupt, possibly with coma as the first 
indication. A sudden onset is frequently 
the case in individuals possessing some 
degree of resistance to the infection. Re¬ 
sistance may even be of such an order that 
symptoms are not evident until a relatively 
high density of parasites in the peripheral 
circulation has been reached. Following 
onset the type of attack experienced by a 
person will naturally depend upon many 
factors concerning the individual, such as 
inherent resistance to infection, previous 
malarial infection and general physical con¬ 
dition. 
Fever. The paroxysm, which may be re¬ 
garded as the unit of the patient’s febrile 
reaction to the infection, is, in P. falciparum 
as in the other malarias, usually ushered in 
by chilly sensations, if not a frank rigor, 
and usually terminates with a period of 
diaphoresis. Presumably it is due to the 
release of the merozoites at the time of 
sporulation, which act as a foreign protein; 
certainly the symptom complex is compar¬ 
able to that seen following the intravenous 
introduction of a foreign protein. Whether 
the intact merozoites can initiate the par¬ 
oxysm or whether a preliminary breaking 
down of some of them is necessary, is not 
known. 
In the majority of instances the tempera¬ 
ture is below 100° F and not infrequently 
