Relapse of rickettsial Mediterranean spotted fever and murine typhus after treatment with chloramphenicol.

In the years 1975-1984, 132 patients with rickettsial Mediterranean spotted fever and murine typhus were treated with chloramphenicol or tetracycline. Among the 24 patients who received chloramphenicol ten relapsed and one failed to respond at all. None of the 108 recipients of tetracycline suffered a relapse. It appears that tetracycline should serve as first-line therapy in several rickettsial diseases.