Infection with this organism during pregnancy can cause congenital hydrocephalus.For the above patient, select the most likely infecting organism.

Congenital toxoplasmosis is initiated in utero usually as a complication of a primary infection. Infants may be asymptomatic at birth but later can present with a multitude of signs and symptoms, including chorioretinitis, strabismus, epilepsy, and psychomotor retardation. The presence of hydrocephalus is a bad prognostic sign.