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194 CHAPTER 8

If explanations from the early Egyptian Ebers The actual parasitic worm of S. japonicum was not
Papyrus are not accepted as documentation of the discovered and described until 1904 by Fujiro Katsurada.
description of schistosomiasis in the earliest medical In 1913 the development of the organism during its
literature, the first definitive record would refer to that time spent in the snail host was described by Keinosuke
of an epidemic among soldiers in Napoleon’s army in Miyairi and Masatsuga Suzuki (Cox, 2002). This work
Egypt in 1798 by a French army surgeon. A. J. Renoult regarding the development of the infective form of the
writes that “A most stubborn haematuria manifested parasite occurred two years prior to Leiper’s indepen-
itself amongst the soldiers of the French army . . . dent description of the life cycle of S. haematobium.
continual and very abundant sweats, diminished quantity More extensive discussions of the history of Katayama
of urine . . . becoming thick and bloody.” Thereafter disease are available from a number of sources.
there are numerous reports of illnesses characterized The twentieth century brought about the discovery
by hematuria, particularly among armies involved in of several other species of schistosomes: S. intercalatum
the Boer War (1899 to 1902) that occurred in South and S. mekongi. S. mekongi is prevalent only in the
Africa. The worm S. haematobium was described by Mekong river basin in Asia, which includes much of
the German parasitologists Theodor Bilharz and Carl present-day Vietnam. S. intercalatum is found primarily
Theodor Ernst von Siebold in 1851. Bilharz, with in central Africa. Several other species of schistosomes
Wilhelm Griesinger, made the connection with the have been identified and are known to infect birds and
urinary disease a year later. The common term bilharzia mammals but only cause an irritating dermatitis from
relating to schistosomiasis persists today in many parts the cercariae penetrating human skin. The history of
of the world and is so named after Theordor Bilharz. such an important disease as schistosomiasis involves
And in consideration of the knowledge of the his- a great number of observations, events, and individu-
tory of intestinal schistosomiasis caused by S. mansoni, als. Today a detailed account of the history is given by
Sir Patrick Manson in 1902 first identified the spe- David I. Grove as well as shorter accounts by W. D.
cies that now bears his name. Manson at that time con- Foster, L. G. Goodwin, and R. Hoeppli. Other accounts
cluded that there were only two species of Schistosoma of the studies of schistosomiasis conducted during
in humans. Even though there had been similar sugges- periods of American and British imperialism are pro-
tions by other investigators by that time, Manson’s ideas vided by John Farley (Cox, 2002).
were not accepted by everyone. It was R. T. Leiper who,
in 1915, firmly established the existence of S. mansoni Morphology
as a separate species. During the time that Manson and
Leiper were performing investigations of the Schistosoma The mature female blood fluke measures an average of
species, work independent of these two were ongoing in 1.5 to 2.0 cm, the female being bigger than the male as in
other areas. many parasites, ostensibly to carry and nurture eggs until
The third important species which was undergoing they are ready for development into other stages. The
study sometime before Manson and Leiper were working single most prominent characteristic of Schistosoma ova
in other areas of the world is the Asian form of the dis- is the presence of a spine, although it is not always recog-
ease that became known as Schistosoma japonicum. As nizable for S. japonicum. The S. japonicum eggs are also
early as 1847, Dairo Fujii was working with an ancient rounder than those of the other two species, in addition
disease that had been known for many years but was not to being the smallest of the three. Unlike the other trema-
properly recorded in the Kwanami district of Japan. The todes, Schistosoma eggs are not operculated. The eggs of
report detailing Katayama disease, the disorder that is schistosomes are the most commonly used trait for identi-
now recognized as S. japonicum, was not generally avail- fying the species of organism to be identified (Table 8-2).
able for other investigators until 1909. Fujii was alerted
to the malady when he found agricultural workers who Symptoms
had waded in watery fields. Cattle and horses were also
affected by wasting and abdominal swelling, accompa- Symptoms for most cases of schistosomiasis when symp-
nied by severe rashes on the legs, but the cause was un- tomatic are more than in most of the infections by other
known to him at the time. trematodes. Repercussions of schistosomiasis infections