l68 TROPICAL MEDICINE AND HYGIENE 



preparations are roughly made. The eggs are very 

 resistant. If kept moist the embryo slowly develops, at 

 a medium temperature, in about thirty to forty days, but 

 may remain alive for years, and if such eggs are ingested 

 by man the embryos are set free and become larvae which 

 reach maturity in about five weeks. 



Serious trouble may result from the wanderings of 

 these worms. They may travel up the bile-duct, and 

 reach the gall-bladder or biliary ducts in the liver, and 

 have been known to cause hepatic abscess. They also 

 appear to aid in the perforation of ulcers and to bore into 

 adhesions between the intestine and other organs, and set 

 up abscess or peritonitis. In some such manner they 

 occasionally reach the urinary system and may be expelled 

 with the urine. In children the abdomen becomes 

 flabby and is protuberant, there is often persistent 

 stomach-ache, perversion of appetite, and there may be 

 picking of the nose and frequent attacks of night terrors. 



A person may harbour ascarides and be in perfect 

 health, but if very numerous, or if they occur in debili- 

 tated persons, they cause a certain amount of anaemia 

 and dyspepsia, and have been credited with causing 

 cerebral symptoms. In chronic dysentery the expulsion 

 of worms is so often associated with rapid recovery or 

 improvement that it is not advisable to consider them as 

 harmless. It is a safe rule to expel these worms when 

 their presence has been ascertained. 



Diagnosis can be readily made by examination of the 

 faeces for eggs. 



Treatment. Thymol, eucalyptus oil, /3-naphthol, &c., 

 may expel these worms, but santonin gives the best 

 results, and where no other eggs are found should be 

 always used. This may be given in capsules or dissolved 

 in castor-oil. Four to six grains in an ounce of oleum 

 ricini for children ; some prefer i-grain doses each of 

 santonin and hydrargyrum with creta twice a day for two 

 or three days. 



As a rule the worms are easily expelled, but a patient 



