Abstract
The effect of pretreatment with I. felis and BCG on the re-excretion of T. gondii occysts was studied in 16 coccidia-free cats. Chronically T. gondii-infected cats re-excreted T. gondii oocysts after superinfection with I. felis, and this re-excretion was prevented in cats infected with I. felis before T. gondii infection. Administration of BCG before Toxoplasma infection had no apparent effect on the outcome of the infection.