HEALTH AND DISEASE 317 



the whole, tapeworm infestation does not produce serious illness, the se- 

 vere symptoms mentioned being the exception rather than the rule. Ef- 

 fective treatments for the removal of tapeworms from man have been 

 established, and persons affected should seek the advice of a physician. 



Prevention is simple and effective. To avoid tapeworm infestation cook 

 beef until it is well done. 



THE PORK TAPEWORM 



Aside from being somewhat shorter, as a rule, the pork tapeworm, Taenia 

 solium, bears a very close resemblance to beef tapeworm. Like the beef 

 tapeworm, the pork tapeworm lodges in the small intestine of human be- 

 ings, its head being provided with hooks that afford the possibility of a 

 firmer anchorage to the intestinal wall than in the case of the beef tape- 

 worm, which lacks this armature. Ordinarily the pork tapeworm is from 

 about two and one half to five feet long, but it may attain, at times, a length 

 of about twenty-five feet. Its life cycle is essentially similar to that of the 

 beef tapeworm, except, of course, that the hog serves as the intermediate 

 host. Human beings become infested with the pork tapeworm by swallow- 

 ing infested raw or insufficiently cooked pork, and hogs in turn become 

 infested with the cystic stage by swallowing feed or water that has become 

 contaminated with human excreta passed by infested persons. The life his- 

 tory of the pork tapeworm thus consists in an alternation between two 

 hosts, man and swine. The reduction in the incidence of infestation in swine 

 necessarily leads to a reduction in the incidence of infestation in man, and 

 vice versa. 



Actually the pork tapeworm is very rare in man in this country; the 

 rarity of this parasite in human beings is directly correlated with the rarity 

 of the cystic stage in swine. This is a very fortunate situation, because from 

 the view-point of its bearing on human health, the pork tapeworm is far 

 more dangerous than the beef tapeworm. So far as the production of in- 

 testinal disturbances and nervous symptoms in infested individuals is con- 

 cerned, the two species under consideration are on a par. Unfortunately, 

 however, man is also capable of serving as an intermediate host of the pork 

 tapeworm and thus becoming infested with the cystic or bladderworm 

 stage. Since the cysts may lodge in such organs as the heart, the brain and 

 the eye, an infestation in man with the cystic stage of pork tapeworm may 

 lead to serious consequences and often does. Persons harboring the pork 

 tapeworm in the intestine might accidentally contaminate their hands with 

 the tapeworm eggs. It requires but little imagination to see how the hands 

 thus contaminated might transfer the eggs to mouth and thus pave the 

 way for an infection of the muscles and of such vital organs as the heart, 

 brain and eyes. Several years ago a medical officer of the British Army re- 

 ported the pork tapeworm as a rather common cause of epilepsy in British 

 troops returning from abroad, presumably from places where the cystic 



