Treatment of tick-bite fever with erythromycin

Because of the occasional need for an alternative drug for the treatment of tick-bite fever, a study of the value of erythromycin for the variety of tick-borne typhus fever occurring in southern Africa was undertaken. In guinea-pigs erythromycin 125 mg/kg for 5 days largely prevented the fever and other signs of the infection, but did not prevent the serological reaction as determined by the rickettsial complement fixation test. A series of 17 human patients were treated for 4 days with erythromycin 500 mg 6-hourly for adults and 30-50 mg/kg/d in 4 divided doses for children. Eleven patients appeared to respond favourably. It was concluded that erythromycin does not have as specific a value as tetracycline in the treatment of tick-bite fever, but that when tetracycline is contraindicated erythromycin is a useful alternative drug.