Treponematoses in Gambia, West Africa

Abstract

1. (1) Surveys for treponemal disease were made in Gambia, West Africa, of villages of the main tribes scattered throughout the country. Approximately 7,500 persons were examined once during the dry season and again during the rains. Serological investigations employing S.T.S. and T.P.I. tests were undertaken in London. 2. (2) The early lesions of yaws, i.e. florid lesions on the skin, were found in one village, and a second form of non-venereal treponematosis known locally as siti was found in four out of five villages of the Fula tribe. 3. (3) The early lesions of siti occurred on mucous membranes of the mouth, and the tip of the penis of small boys before puberty. Florid lesions were found on the vulva and round the anus. Circinate lesions were found on the skin and also axillary lesions resembling yaws. Sera from the above lesions contained treponemes morphologically identical with T. pallidum, and the serological tests in these cases were positive. 4. (4) The most common late manifestation of treponemal disease in Gambia appeared to be depigmentation, particularly depigmentation of the hands. It has been shown statistically that depigmentation of the hands is probably due to treponemal disease. Other late manifestations were too infrequently seen for accurate conclusions to be drawn. 5. (5) No evidence was found of the development of lesions of the cardiovascular or central nervous systems. 6. (6) Contractures of the fingers were encountered in 3 per cent. of the female population and in 1.9 per cent. of the male population. These figures are significantly different. No statistical evidence was found to suggest that contractures were the result of treponemal infection. 7. (7) Siti appeared to be transmitted by the use of a common drinking-cup and common food-bowl, and close personal contact. 8. (8) Gambia lies at the edge of the tropical rain-belt, and the climatic conditions are unusual in that there is one short, intense rainy season and a long dry season, giving for part of the year a desert climate and for a short part of the year a humid climate. The fact that both yaws and the other form of non-venereal treponematosis were found side by side is believed to be further evidence in the hypothesis of the common aetiological agent of the treponematoses, and that the clinical manifestations are affected, among others, by climate. 9. (9) It is suggested that the term “endemic syphilis” is a misnomer and should be abolished; and that, with the exception of the Bosnian form of the disease, all the non-venereal treponematoses, including yaws, should be classed together.