FLATWORMS AND THREADWORMS 



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Trematode Infections. 



Schistosomum haematobium (Fig. 180), (also called Bilharzia 

 haematobia), which causes the disease known as bilharziosis, is by no 

 means uncommon in tropical countries such as Asia and Africa, and is 

 sometimes found in Europe and America. 



The mature worm lives in the branches of the portal veins so that 

 the eggs are easily distributed (with the blood) into the liver and other 

 organs of the body. The eggs, which are the true cause of the disease, 

 have a tendency to affect the urinary apparatus, causing a bloody urine 



to be discharged and also causing de- 

 structive and over-growth processes in 

 the bladder, urethra, and surrounding 

 parts. All these infected parts are 

 loaded with eggs so that abscesses and 

 fistulas form. Similar conditions may 

 take place in the rectum. Ten per cent 

 of all patients in Cairo were found to 

 be infected, while seven and a half per 

 cent of all army recruits in Egypt 

 showed the eggs in their urine. 



Schistosomum Japonicum is the 

 Japanese species. 

 This blood-fluke is peculiar in that it has separate sexes, the male 

 being carried about by the female in a gynaecophorous canal (Fig. 181). 

 The eggs are oval and a terminal spine is found at one end. The 

 eggs hatch in water, so they may be taken in with raw vegetables or even 

 with drinking w r ater. 



It is an interesting fact that animal parasites often cause no pain, 

 but are on that very account the more dangerous because the patient 

 infected pays no attention to his infection and the disease thus grows 

 constantly worse without any attention being given it. 



Schistosoma Japonicum vel cattoi. This species is common in China, 

 Japan, and the Philippines. The disease produced by it is called Kata- 

 yama disease. The liver hardens and the spleen enlarges. There is dys- 

 entery and a loss of blood. 



The eggs are smaller than S. haematobium and they do not have the 

 terminal spine. 



In Formosa, Paragonimus Westermani (Fig. 182), (Asiatic lung- 

 fluke or bronchial fluke), is often found as a parasite infecting the lungs 

 of man. It is also found in the brain where it causes death from 

 pressure. 



The worm is 8-16 mm. long and 4-8 mm. broad, and is pinkish or red 

 in color. The disease it causes is often confused with tuberculosis, al- 

 though the microscope shows many eggs in the sputum. The liver, 

 brain and eyelid are the most common points affected. 



