Strain variation in Entamoeba histolytica I. Correlation of invasiveness in rats with the clinical history and treatment of the experimental infections

Abstract

1. Eleven strains of Entamoeba histolytica were isolated from contact carriers and all proved non-invasive to rats.2. Three strains from cases showing symptoms proved invasive to rats.3. The treatment of murine infection with non-invasive strains with emetine hydrochloride shows that most of them were successfully cured with six daily oral doses of 2 mg./kg., though one was not susceptible to this dose. Another proved refractory to 4 mg./kg.4. The results of previous work with kittens are discussed in the light of the present observations.