[Doxycycline in experimental rickettsial infection].

The effect of doxycycline on R. prowazekii and R. sibirica was studied in comparison with that of tetracycline on two infection models, i. e. chick embryos and guinea pigs. The activity of doxycycline in the experiments with chick embryos was higher than that of tetracycline, the drug being more active against R. prowazekii than R. sibirica. The use of doxycycline in the treatment of the guinea pigs infected with R. prowazekii resulted in very rapid and stable decrease of the temperature. When used within the incubation period the drug prevented the infection development. Doxycycline was less effective in infections caused by R. sibirica.