Experimental toxoplasmosis of the central nervous system in rabbits as a model of human infection

Rabbits were infected by intraventricular injection of tachyzoites of the RH strain of Toxoplasma gondii and examined for a laboratory evidence of toxoplasmosis at the advanced stage of infection. From the examined samples of cerebrospinal fluid (CSF), blood and brain sections, the samples of spinal fluid appeared frequently negative for toxoplasmosis in spite of very sensitive methods that had been used in the diagnostic procedure. Most probable explanation of the low efficiency of diagnostic methods based on examination of the spinal fluid was a slow circulation of the CSF, which did not promote dissemination of parasites within cerebral ventricles and subarachnoid spaces. The results of the studies allowed to conclude that rabbits infected by intraventricular injection of II gondii provide a good model of toxoplasmosis of the central nervous system which may facilitate evaluation of the efficiency of diagnostic procedures used to differentiate the condition.