Experimental louse-borne relapsing fever in the grivet monkey, Cercopithecus aethiops. III. Crisis following therapy.

Eight grivet monkeys infected with Borrelia recurrentis received tetracycline (12.5mg/kg body weight) on the 3rd or 4th day of spirochetemia. Leukopenia, fever, hyperpnea, and tachycardia developed within 2 hours as spirochete counts fell to undetectable levels. These events closely simulated the crisis in human louse-borne relapsing fever in both timing and extent.