Histoplasmosis diffusion in Somalia: study of skin-test and serological survey

Histoplasmin skin-test was applied to 1014 patients in two different parts of Somalia: in Mogadishu, an arid area, and in Jilib, a southern village on the banks of the Juba river. Among these patients only three gave areas of induration greater than 5 mm in diameter; all reactors were from Jilib. Results of a serological survey (latex-agglutination test) of histoplasmosis antibodies among 203 Somalian patients from three villages in river valleys are compared with the results of 171 inhabitants of the town of Mogadishu. Indirect agglutination antibody titers greater than or equal to 20 were found in 21.6% of the Mogadishu population as compared to 52.2% found in the river villages. In 96.2% of our cases in which the two tests were contemporarily used, the skin-test was completely negative despite high titres of positivity in the serological test. The results indicate the existence of founts of histoplasmosis infection in Somalia, particularly in humid areas bordering the rivers rather than in the surrounding arid semi-desert area characteristic of most of the country.