Studies on Loa loa and the first report of Wuchereria bancrofti in the Sudan

Abstract The commonest Chrysops vector of Loa loa in the Southern Sudan has been demonstrated and the course of the embryos' development is described in outline after 300 dissections. Comparison with the Connals ' experiments with infected Chrysops silacea and C. dimidiata in West Africa showed certain modifications both in the development of the embryo and in the habits of the fly. Some facts are put forward from which there is ground for the inference that vectors other than Chrysops also exist in Central Africa. The occurrence, though rare, of W. bancrofti in the Sudan is reported for the first time. The failure to find W. bancrofti at all and O. volvulus very rarely, in association with elephantiasis and hydrocele in this part of the Sudan affords some justification for attributing at least the earliest stages of lymph varix to Loa loa . Attention is drawn to a possible association between this filaria and the disposition to hernia and hydrocele.