Central nervous system viral infections refer to the invasion and replication of a viral agent within the central nervous system (CNS), which includes the brain and spinal cord. These infections are caused by various types of viruses that can enter the CNS through multiple routes, including hematogenous spread, retrograde transmission along neurons, or direct invasion through the olfactory or trigeminal nerves.
Common viruses that can cause central nervous system infections include herpes simplex virus (HSV), varicella-zoster virus (VZV), human immunodeficiency virus (HIV), and enteroviruses. However, there are many other viral agents that can also lead to CNS infections.
The symptoms of central nervous system viral infections can vary depending on the specific virus involved and the affected area within the CNS. In general, common symptoms may include fever, headache, stiff neck, altered mental state, seizures, focal neurological deficits, and meningismus.
Diagnosis of central nervous system viral infections often involves a combination of clinical evaluation, cerebrospinal fluid (CSF) analysis, neuroimaging, and serological testing for viral antibodies. Treatments primarily focus on alleviating symptoms and managing complications, as there are limited antiviral drugs available that specifically target CNS viral infections.
Severe cases of central nervous system viral infections can result in long-term neurological sequelae, particularly if appropriate treatment is delayed or not established. Therefore, early recognition, prompt diagnosis, and timely initiation of appropriate interventions are essential for optimizing outcomes.