Survival of Rickettsia prowazeki in Different Diluents

Abstract

The data presented were collected with the idea of assessing the value of media in common use for work in exptl. typhus. Eastern cotton rats were inoculated intraperit. with cotton rat liver suspension, containing 200-700 50% mortality doses, as detd. by intra-cardial titration. In most tests approx. 4 to 16 50% mortality doses were contained in 0.2 ml. of the inoculum after dilution in the test medium. The media can be divided into those in which rickettsiae survive poorly for a period of 6 hrs.; those in which they survive well for 6 hrs. but not for 24 hrs.; and those in which they survive well for > 24 hrs. Rickettsia survived longest in sterile skim milk.