In 1850, Wilhelm Griesinger, then at the
University of Kiel, was appointed by
Abbas I of Egypt,
Wāli (governor or viceroy) of Egypt and Sudan, to head medical services in Egypt. He responded to the Wāli that he would accept the appointment only if his former student Theodor Bilharz was appointed as his assistant. Von Siebold wrote of his recommendation to Bilharz's father saying, "I can't help it to speak out the wish that the stay of your good Theodor may be a credit to him and to science... I won't believe anything else than that a longer stay in wonderful Egypt would be excellently used by your son. God may save his health." As an authorised
autopsy performer, it was an ideal assignment for Bilharz because autopsy was generally opposed by religious and traditional establishments at the time. Von Siebold gave the original name as
Taenia nana in 1852. In 1851, Bilharz also discovered a novel intestinal flatworm from an infected child in Cairo. Von Siebold named it
Distoma heterophyes in 1852
. English biologist
Thomas Spencer Cobbold created a better generic name
Heterophyes in 1866; thus, the parasite became
Heterophyes heterophyes. Bilharz's specimen became the first known helminth in the family
Heterophyidae.
Discovery of bilharzia and Schistosoma haematobium Ancient Egyptians had recorded urinary disease which can be attributed to
S. haematobium infection. 16th-century BCE medical papyri mention the disease as
aaa that indicates symptoms of urinary bilharzia. The French army physician Adrien-Jacques Renoult reported the disease as
haematurea (bloody urine) in 1808.
Napoleon's army in the late 18th century called Egypt as "the land of menstruating men." This is because of the high prevalence of the disease that severely affected the French army. The cause of the disease was never known. In 1851, during an autopsy, Bilharz discovered an obvious worm from the
portal vein connecting the urinary tract of a dead soldier. It was the first time anyone had seen a parasitic worm that lived inside a blood vessel. Not really knowing what kind of worm it was, he wrote to his former zoology professor von Siebold at Breslau on 1 May 1851:He also added an identification puzzle:[It] had a flat body and a spiral tail at least ten times as long as the body... The tail was a continuation of the flat body of the worm itself, rolled sideways towards the stomach surface in a half canal; the forked blind end of the intestinal canal extended into it very plainly. What then is this animal? In spite of its long tail, it probably cannot be called a cercaria [a fork-tailed larva of trematodes], which is completely different, histologically and morphologically.As unique among flukes, the schistosomes have two bodies – a female which is like a roundworm and a male which is curled-up fluke – that are combined permanently (a condition called
in copula) to make up individual adult worms. Bilharz had discovered a male fluke. He knew it has similarities to other flukes, especially the two mouth-like
suckers (now called oral sucker or acetabulum and ventral sucker), for which he immediately used the name
Distomum, a Greek for two mouthed. But the rolled-up body made him think that it was a roundworm. At the end of May, he found a female specimen from another corpse that was all wrapped up by the same kind of worm he had discovered. It occurred to him that the worm was an extraordinary fluke, exclaiming, "Something more wonderful, a trematode with divided sex." Describing his observation in a letter to von Siebold on 18 August, he wrote:You can imagine my surprise when I saw a trematode [fluke] protruding from the frontal opening of the groove and moving back and forth; it was similar in shape as the first, only much finer and more delicate... [The female] was completely enclosed in the groove-shaped half canal of the male posterior, similar to a sword in a
scabbard. By March 1852, Bilharz also found many eggs from the bladders of the fluke-infected individuals, indicating that those were of the parasites. He could not establish what the eggs did to cause the disease and suspected them as the cause of kidney stone (
nephrolithiasis) and other kidney problems. Griesinger had thought that the fluke caused dysentery, but Bilharz found that it was responsible for
urinary tract diseases including haematuria as well. Von Siebold reported the discovery in
Zeitschrift für Wissenschaftliche Zoologie, the journal he edited, in 1852. Bilharz then published in the following volume of the same journal the complete description of the parasite structure and the disease it caused. He referred to the disease as "endemic haematuria of warm climates" and the "dysenterische Veränderung des Dickdarms" (dysenteric pathology of the colon). By then, he established that the disease (its pathology) was caused by the eggs and not the worms themselves. He reported his observations in the journal
Wiener Medizinische Wochenschrift in 1856. Adding to the confusion,
Distoma and
Distomum had been interchangeably used to describe different species of flukes. Even
Distomum haematobium was sometimes written as
Distoma haematobium. The parasite thereby became
Bilharzia haematobium, and with it von Hemsbach introduced the name of the disease as bilharzia. Not knowing von Hemsbach's publication which had limited circulation at the time,
David Friedrich Weinland proposed the name
Schistosoma (a Greek term for "split body" reflecting the separation of male and female in an individual) in 1858. After a century of debate and confusion on the name, in 1954, the
International Commission on Zoological Nomenclature (ICZN) officially declared
Schistosoma haematobium as valid on the ground of
priority rule. However, if true priority was to be followed,
Bilharzia haematobium should have been adopted. In 1949, the
World Health Organization adopted the name bilharzia for medical terminology. When ICZN validated the name
Schistosoma haematobium in 1954, it specifically recommended that the disease be called bilharziasis. Following the valid scientific name, schistosomiasis became widely used,` Towards the end of the 19th century, Cobbold noted as "without question, [
S. haematobium is] the most dangerous [of human] parasite[s]." German anatomist,
Gustav Fritsch called it "schlimmerer feind der menschheit" ("the worse enemy of humankind"). A series of observations following the initial discovery by a British Surgeon
Reginald Harrison in 1889 that
S. haematobium causes
bladder cancer, the WHO
International Agency for Research on Cancer (IARC) declared the fluke as
Group 1 carcinogen in 2009. It became the first fully proven
carcinogenic organism,
Discovery of Schistosoma mansoni When Bilharz found parasite eggs from infected individuals in March 1852, he noted unique characteristic of schistosome eggs, as each egg has a spine, which he called "pointed appendage." He observed the spiny eggs in the bladder as well as in the intestine. He wrote to von Siebold that some of the eggs were different in having terminal spines while some had lateral spines. Bilharz also noted that the adult flukes were different in anatomy and number eggs they produced. His drawings depicted which were later identified as those of
S. mansoni adults''.
Electric organs of fish After the discovery of bilharzia, Bilharz researched on the
electric organs of the Egyptian
electric fish popularly known as thunderfish. Electric fishes had been well known in Egyptian history and commonly depicted in ancient
hieroglyphics. For this historical importance, Bilharz considered his research on electric organs more valuable than bilharzia, ==Later life and death==