Viral Meningitis

Viral meningitis is the inflammation of the meninges, most often caused by enteroviruses, such as coxsackieviruses and echoviruses.

These viruses usually spread through the fecal-oral route, via contaminated hands or surfaces.

Once inside the body, the virus first replicates in the epithelial cells of the gastrointestinal tract.

From there, it may enter the bloodstream and travel to the central nervous system.

To reach the brain, the viruses must cross protective barriers.

One route is by infecting the endothelial cells forming the blood–brain barrier to enter the brain tissue.

Alternatively, the virus may pass through the choroid plexus epithelium, which forms the blood–cerebrospinal fluid or CSF barrier, enabling direct access to the CSF.

Once in the CSF, the virus activates the host’s immune cells to release cytokines.

This recruits additional immune cells and drives inflammation of the meninges, producing headache, fever, and neck stiffness.