the larval stage of cestoda worm.

Taenia multicepd 

Echinococcus spp.

 Acanthamoeba

Paragonimus spp

Schistosoma spp

Taenia solium, larva (cysticercus cellulosae)

Echinococcus granulosus larva  (brain hydatid cyst)

Invasive entamoeba histolytica (trophozoite) (cns)

Pleurocercoid larvae of fish tape worm (dyphyllobothrium latum) may reach cns temporally and cause epilepsy (by visceral larval migraines) then return to intestine

I agree with Khetam Qaid Mayee: Chances are big that Toxoplasma would be nr.1 (in humans anyway)...

Hi Dr.

Many parasite can infect or effect on the nervous system like hydrated cyst, cysticercus cellulosaeT.gondii, Sarcocystis, B. Canis, B. bovis....etc

Thanks to all of you. 

Naegleria

 Acanthamoeba

Paragonimus spp

Schistosoma spp

Echinococcus (Hydatid Disease)

Toxoplasma

Acanthamoeba,Schistosoma,Toxoplasma 

Toxoplasma gondii

Naegleria

Schistosoma spp

Taenia solium

Echinococcus granulosus 

Trypanosoma bruci

Article PREVALENCE TRYPANOSOMIASIS OF STRAY DOG IN BAGHDAD CITY, IRAQ

Trypanosoma, Toxoplasma, Naegleria, cysticercosis and embolic lesion from eggs of Schistosoma & Heterophyes.

Trypanosoma evansi, Toxoplasma, Schistosoma, Plasmodium falciparum