Is immuno-protection against Toxoplasma strain specific?

Two different strains of Toxoplasma gondii were isolated from feline faecal deposits in two villages: Rommana (Northern Sinai) and El-Ekhewa (Sharkyia Governorate) as evidenced by their entirely different pathogenic effect and immune response in laboratory Swiss Webster mice. A man holding both villages as mutual residences, who was already proved to get acute toxoplasmosis twice made us avid to search for the presence of different strains in the two localities. The present study throws a suggestion that repeated Taxoplasma infection could be due to difference in strains.