Parasitic and Fungal Infections of the CNS

Central nervous system (CNS) infections involve the brain, spinal cord, optic nerves, and their protective membranes. These infections are medical emergencies with high morbidity, mortality, and potential long-term complications that significantly affect quality of life. Parasitic infections are common in regions with poor sanitation but can also occur in non-endemic areas due to international travel and immunosuppression from Human Immunodeficiency Virus (HIV) or post-transplant medications. Fungal and parasitic CNS infections present with diverse clinical symptoms and are often associated with high mortality in resource-limited settings. Survivors frequently suffer from neurological complications such as motor and sensory deficits, cognitive impairment, and seizures. Diagnosis can be challenging due to the complexity of parasite life cycles, geographic variations, and overlapping clinical features. This chapter reviews major parasitic and fungal pathogens affecting the CNS, highlighting their pathogenesis, diagnostic approaches, treatment strategies, recent developments, and key aspects of prevention and control.