A 26-year-old woman, at 24 weeks of gestation, presents to her obstetrician with mild fatigue and low-grade fever for the past week. She denies respiratory symptoms but reports occasional headaches and lymph node swelling in her neck. She has no significant medical history and is not on any medications. She has a pet cat at home. Physical examination reveals palpable, non-tender cervical lymphadenopathy. She is concerned about the risk of congenital toxoplasmosis to her fetus. What is the preferred treatment for a pregnant woman diagnosed with acute toxoplasmosis to prevent vertical transmission?
