Applied Biology 785 



A. Human Diseases — Cont'd 



2. Human Diseases 



Caused By Worms 



' (a) Flatworms (Platy- 



helminthes) 



( 1 ) Pork tapeworm 

 (Taenia solium) 

 (Fig. 182) 



(2) Beef tapeworm 

 (T. saginata) 



(3) Chinese liver 

 fluke {Clinorchis 



■sinensis) 



Transrhitted by eating infested, improperly cooked 

 pork; common wherever such pork is eaten 



Transmitted by eating infested, improperly cooked 

 beef; common wherever such beef is eaten (Fig. 

 183) 



Lives in man in the Orient; transmitted by eating 

 improperly cooked, parasitized fish (Fig. 373) 



Fig. 373. — Chinese liver fluke {Clinorchis sinensis) photographed, showing the 

 internal organs of an adult. Contrast with the sheep liver fluke (Fasciola 

 hepatica). (Figs. 180, 181 and 374), (Copyright by General Biological Supply 

 House, Inc., Chicago.) 



(b) Roundworms 

 (Nemathelmin- 

 thes) 



(4) Trichinosis or 

 pork roundworm 



(Trichinella 

 spiralis) 

 (Fig. 100) 



(5) New world 

 hookworm 

 {Necator 

 americanus) 

 (Fig. 99) 



(6) Elephantiasis 

 {Wuchereria 

 {Filarial 

 hancrofti) 

 (Fig. 101) 



(7) Human ascaris 

 {Ascaris 

 lumhricoides) 

 (Fig. 184) 



Transmitted by eating infested, improperly cooked 

 pork; larvae may pass from human intestine into 

 muscles and lymphatic system 



Transmitted through skin from infested soils; para- 

 sites may be present in human blood, lungs, in- 

 testines, etc.; causes shiftlessness and anemia 

 (loss of blood through intestine) ; common in 

 South 



Transmitted by night-flying (nocturnal) mos- 

 quitoes from blood in skin of patient to next 

 person; in daytime the larval parasites (1/100 

 inch long) live in deeper human tissues (lungs, 

 larger arteries, etc.) ; parasites enter human 

 lymphatic system, obstructing the flow of lymph, 

 causing typically enlarged limbs, etc. 



Eggs and larvae carried to human mouth by in- 

 fested foods, water, or soil; the larvae in the 

 human intestine migrate through the blood and 

 lymphatic system to liver, lungs, and heart and 

 eventually back to the intestine 



