The spread of tick-borne borreliosis in West Africa and its relationship to sub-Saharan drought.

In West Africa, tick-borne relapsing fever is due to the spirochete Borrelia crocidurae and its geographic distribution is classically limited to the Sahel and Saharan regions where the vector tick Alectorobius sonrai is distributed. We report results of epidemiologic investigations carried out in the Sudan savanna of Senegal where the existence of the disease was unknown. A two-year prospective investigation of a rural community indicated that 10% of the study population developed an infection during the study period.

Tick-borne borreliosis in west Africa: recent epidemiological studies.

Tick-borne borreliosis in West Africa is classically considered a rare disease whose geographic distribution is limited to Saharan and Sahelian regions. We report results of epidemiological investigations which indicate that tick-borne borreliosis is endemic in all regions of Senegal north to the 13 degrees 30'N latitude and is a major cause of morbidity in these areas. Our findings indicate a considerable range extension for the vector tick Alectorobius sonrai and suggest that the persistence of Subsaharan drought is responsible for a large spread of tick-borne borreliosis in West Africa.

Microcalorimetric study of the interaction of human and bovine serum albumins with tryptophan and tryptophan analogs.

The thermodynamic parameters for the protein-ligand binding have been obtained by microcalorimetry on three albumin samples (fatty acid free human serum albumin (I), fraction V human serum albumin (II), and fraction V bovine serum albumin (III)) bound with l-tryptophan (A) and three-ring tryptophan analogs (B and B*). The percentage, mu, of binding molecules (equivalent to the number of sites) is found to be 1.0 for I and 0.