Oxyuris vermicularis, the seat-worm, or thread-worm, also called the awl-tail, or maggot, is a small round-worm which in man sometimes infects the large in testine and the lower part of the small intestine. The length of the female is 10 millimetres and pointed at the caudal end like an awl; the male is 4 milli metres in length with a blunt posterior extremity provided with a spiculum. The • eggs are brought forth by the female in enormous numbers, and are only devel oped in the intestinal tract of man or beast. These eggs are very vigorous and offer marked resistance to external agencies.
The most common symptoms of the thread-worm are itching of the anus; this is worse at night, and is accompanied by disturbed sleep and extreme irritabil ity. The irritation resulting from the presence of the parasite may also be the cause of masturbation in both sexes.
Treatment.—In the treatment of thread-worms (Oxyuris vermicularis) very little has been offered in recent literature that bears the stamp of nov elty. The most important agent is the mechanical and chemical cleansing of the lower bowel and the use of such drugs by the mouth as are known to either paralyze or destroy them. The indications are summed up by Sansom: first, to expel the intruders and all their ova by the use of simple aperients, kept up for several weeks, along with entero clysis of pure water, which causes the parasites to swell up and burst; second, to prevent the entrance of ova into the digestive tract by the use only of food and drink which have been thoroughly cooked. Preventive measures, among in fected children, are of great importance (Nicholson), such as keeping the nails short and clean, dipping them frequently into quassia, and enforcing isolation until a cure is effected. For the intestinal irrigation plain water suffices, if used re peatedly and for a long-enough period, which is daily for a week or two or twice a week for five or six weeks. The in fusion of quassia enjoys an especial repu tation in this connection, and is the rem edy which we have usually used, from three to five irrigations, on consecutive days, usually sufficing; in obstinate cases, where the infection reaches very high up, more may be required.
Solutions of Castile soap are recom mended by Monti, continued for from one to three weeks. A. Gremand regards
sulphur-water as the most satisfactory, per etyma as well as per os. W. N. King recommends a saturated aqueous solution of socotrine aloes, 1 ounce of which is in jected into the bowel at bed-time and re tained, and this should be repeated for several consecutive nights; it is then dis continued, and, upon a return of the para site, is again used. Engel recommends a bichloride solution 1 to 2000, but this agent should be most cautiously used.
For internal administration the first item to be considered is diet. The addi tion of garlic to the food enjoys a very ancient reputation.
Of drugs, the most important are those which act as laxatives, aromatics, and in testinal antiseptics. Sidney Martin rec ommends a mixture of rhubarb, carbon ate of magnesia, and ginger in small doses.
For the relief of the anal pruritus mer curial ointment is useful; it serves the double purpose of soothing the parts and preventing the escape of the worms from the bowel.
It must be borne in mind that fre quently the removal of these apparently trifling parasites is attended with the greatest difficulty, especially where there is considerable catarrhal inflammation of the colon. It is most essential in apply ing the irrigations that they be given thoroughly and in such a way, in obsti nate cases, that they reach, if possible, the CfeCUM. The injection should be given through a long catheter or rectal tube, which must be cautiously inserted well up beyond the sigmoid flexure, the child lying on its left side, for five utes, then on its right side for five rites,—preferably a much greater period.
Trichocephalus dispar, or whip-worm, is an entirely harmless, hut quite com mon, intestinal parasite frequently found in the ccecum.
The size of male and female are sim ilar: from 4 to 5 centimetres in length. The forepart of the body is narrow and the afterpart much thicker, giv ing it the appearance of a whip. The sexual organs are in the thicker portion, and in the posterior end a spiculum. The eggs are elongated and oval in shape, and 50 millimetres long; they possess a thick, brown shell, at each pole of which is a clear globular mass. They develop slowly and first in water and damp earth, and are very resistant to cold and dry ness. The Trichocephalus occurs also in the domestic animals.