304 DISEASES DUE TO HELMINTHS 



nant female tlien settles down ultimately in a place where it can deposit 

 its young in or close to water. The parts chosen are : — 

 (i) The ankle or lower leg in 85 per cent, of cases. 



(2) The backs of water carriers in India (doubtful). 



(3) Rarely about the knee joints. 



The life span of a parent worm is abt)ut ten to twelve months. 



Therefore, the embryos are discharged into the water where they 

 must be taken up bv an intermediate host, e.g., cyclops in which they 

 develop into mature larvae in five weeks but in which they can survive 

 for 41 days. The larvcC are then swallowed b\' man, or as some assert, 

 they enter the skin of the subject while he is bathing or standing in 

 the water or mud. The mature worms form in about one year and 

 they can persist for ten to twelve months during A\hich time they dis- 

 charge their embrvos. 



The life cycle is broken : — 



(i) Bv death of the embryos as a result of sepsis of the wound. 



(2) Bv death of the embryos when there is no water near at liand. 



(3) If nO' cyclops is present in the water or if the cyclops dies or is 

 not ingested by man. 



(4) If the larvce are immature when ingested or fail to escape from 

 the body cavity of the c\'clops. 



(5) If there are not the two sexes in the embryos and if the female 

 is not impregnated while wandering through the connective tissue. 



PATHOLOGICAL LESION. 



A small bulla on the surface of the skin about the external malleo- 

 lus marks the anterior end of the female worm. The bulla bursts, 

 the uterus prolapses, the young are discharged and a jjortion of the 

 worm is often extruded, A\hic]i the natives t\\isl around a stirk in an 

 attempt to extract it. This area is very liable to become septic. 



SYMPTOMATOLOGY. 



An ulcer appears as above. Urticarial eruptions are not un- 

 common. 



Rigors and fever may occur. Eosinophilia may go up to 13 per 

 cent. 



Synovitis and arthritis are rare. The writer extracted one from over 

 the internal tuberosity of the knee after synovitis. The svnovitis 

 trouble cleared up when the worm had been removed. 



TREATMENT. 



The worm lies zig-zag and even though nuicli may be removed the 

 posterior end may have remained in the same place, the worm has only 

 been straightened in the majority of attempts to remove it by twisting 

 it around a stick. 



