[Focus of borreliosis in Gisenyi (Rwanda)].

As a result of the increase of relapsing fever cases in a rural area of West-Rwanda, a study of ticks collected in the houses has been performed. Ornithodoros moubata specimens were found in large amount. In patients, fever is the most frequent symptom. Serological tests performed in the surrounding area of patients with Borrelia in the blood are often positive, this confirming the ancient existence of the disease among inhabitants.