DRACONTIASIS 301 



DRACONTIASIS. 

 DISTRIBUTION. 



I'ropical Africa. In the Sudan it is to be found at Gallabat, 

 Gedaref, Upper White Nile, Kordofan and the Bahr-el-Ghazal 

 Province. India, Persia, Turkestan, Arabia and a few places in South 

 .America where it has been carried from Africa, such as al British 

 Guiana. 



It is also present in the Fiji Islands. 



It has been seen in Europe. 



In parts of the Deccan at certain seasons 50 per cent, are infected. 



In parts of the West Coast at certain seasons 95 per cent, are 

 infected. 



The disease has been reported in horses, oxen, dogs, &'C. 



THE PARASITE. 



Dracunculus medinensis. (Guinea worm.) 



Perhaps this was the fiery serpent of Moses as he knew the method 

 of twisting the creature about a stick. 



The host is man. 



The intermediate host is the Cyclops quadricornis. 



This worm is the largest of human lilaria, its average length being 

 about 40 inches with extremes of 12 to 70 inches. 



The female, of which we know the most, is a long, white worm 

 with a hooked tail and a large uterus which occupies nearly the whole 

 of the body cavity. The embryos when ready are evacuated from it 

 at the anterior end near to the mouth. The uterus protrudes througli 

 the head parts, rupturing them (Leiper), and when about one inch of 

 it has passed the sac fills with opaque fluid and ruptures. When a 

 little water is added the motionless embrvonic forms uncoil themselves 

 and swim about. 



LIFE-HISTORY. 



The young are discharged into fresh water soon after the parent 

 has broken the overlaying skin and before sepsis has set in. These 

 young forms are taken into the body cavity of a cyclops where in about 

 five weeks they will develop into mature larvae. These are taken into 

 the human stomach with drinking water or vegetables, where the o'2 

 per cent, of HCl kills the cyclops and at the same time stirs up the 

 larvce to such activity that they break through the cyclops at the mouth, 

 anus and genital opening. They then swim about in the gastric fluid 

 after which they penetrate the gastric wall and so reach the mesenteric 

 connective tissue. Here they copulate and the males die. The preg- 



