A BLOOD-DESTROYING SUBSTANCE IN ASCARIS 

 LUMBRICOIDES 



[PRELIMINARY PAPER] 



By Benjamin Schwartz 



Zoological Division, Bureau of Animal Industry, United States Department of Agri- 

 culture 



RELATION OF ASCARIS INFECTION TO ANEMIA 



The view that parasitic worms secrete toxic substances which are 

 absorbed by the host and which are responsible to a considerable extent 

 for the symptoms which often accompany parasitic infections, has received 

 strong support from experimental work with the body fluids and extracts 

 of the various species of Ascaris that parasitize man and domesticated 

 animals. Numerous experiments have shown that the body fluids and 

 extracts of these worms produce decidedly harmful effects on susceptible 

 animals into which they are injected. While it must be admitted that 

 the effects of such injections are far more pronounced than the symptoms 

 usually exhibited by animals that are known to harbor in their intestines 

 numerous ascarids, experiments of this nature have thrown considerable 

 light on the pathology of Ascaris infection, and have also added to our 

 knowledge of the metabolic products of these parasitic worms. 



That Ascaris may cause anemia is the opinion of various observers. 

 According to Schimmelpfennig (gY and Weinberg and Julien (14) » the 

 post-mortem appearance of horses infected with ascaris suggests a 

 condition of anemia. As far as man is concerned, a number of clinicians 

 have emphasized the importance of Ascaris lumbricoides in relation to 

 anemia. Thus, Demme (5) reports two cases of grave anemia in 

 children, resembling pernicious anemia, which he attributed entirely to 

 the presence of A. lumbricoides in the intestine. In one case death 

 occurred, the cause of the disease not having been recognized, whereas 

 in the second case complete recovery followed anthelmintic treatment. 

 Francois (5) cites a number of cases of severe anemia resembling that 

 of ancylostomiasis, in which A. lumbricoides was evidently the causal 

 factor. Guiart (8) considers Ascaris to be a causal agent in anemia, 

 ranking close to Dibothriocephalus and Ancylostoma in importance. 



' Reference is piade by number (italic) to "Literature cited," p. 237-238 



Journal of Asricultural Research. Vol. XVI, No. 9 



Washington, D. C. (253) Mar. .i, 1919 



i-j Key No. A-46 



