What causes meningitis?

Meningitis is a condition characterized by inflammation of the meninges, typically caused by various pathogens, including: 1. Bacterial meningitis: Common bacteria include Streptococcus pneumoniae, Haemophilus influenzae type B, and Neisseria meningitidis (also known as meningococcus). This type of meningitis is very serious and requires immediate treatment. 2. Viral meningitis: Common viruses include enteroviruses, herpes simplex virus, varicella-zoster virus, and West Nile virus. Most cases of viral meningitis are mild, but in some situations, it can be life-threatening. 3. Parasitic meningitis: Less common, caused by parasites such as amoebas or Plasmodium species. 4. Non-infectious meningitis: Rarely, autoimmune diseases, tumors, or certain drug reactions can lead to meningeal inflammation. Symptoms of meningitis include severe headache, fever, nausea, vomiting, sensitivity to light, neck stiffness, and changes in behavior. If these symptoms occur, immediate medical attention should be sought.