What of the mongoose?  The only study that was done was on the mainland concerning toxoplasmosis where there were only cats.
Surely any carnivore would also process the parasite too.  
1/5 of the human population have already had the parasite and show positive for the antibodies.  Most people don't even know they have had it. The CDC rates this malady as rare to very rare.
With all the human waste going in the oceans could it be that the parasite is coming from man?  More study is surely needed.