11/29/2025
Meningitis causes
Infectious diseases (caused by something harmful from outside your body) and noninfectious conditions cause meningitis. Specific causes of each type include:
Bacterial meningitis: Common bacteria include Streptococcus pneumoniae, group B Streptococcus and Neisseria meningitidis.
Viral meningitis: Viruses include non-polio enteroviruses, like group B coxsackievirus and echovirus.
Fungal meningitis: Some fungi that can cause meningitis include Cryptococcus neoformans, Coccidioides immitis and Candida.
Parasitic meningitis (also called eosinophilic meningitis): Parasites that can cause this include rat lungworm and Baylisascaris procyonis (a roundworm).
Drug-induced aseptic meningitis (DIAM): NSAIDs and antibiotics are the most common causes of DIAM. But overall, it’s rare.
Carcinomatous meningitis: Cancer cells get into your meninges and cause inflammation. It can occur in the advanced stage of any cancer.
Post-traumatic meningitis: This can result from brain or head injury.
Autoimmune meningitis: Autoimmune conditions like lupus and rheumatoid arthritis are causes.
How does someone get it?
You can get meningitis in many ways, depending on whether the cause is infectious. You could get it:
From a contagious bacterial or viral illness passed person-to-person
From food contaminated with something infectious
From fungi in the environment that you breathe in
As a complication of noninfectious conditions, like cancer or lupus
From a head injury or as a complication of brain surgery
As a side effect of a medication
Meningitis itself — swelling of the meninges — isn’t contagious. But some of its causes are. Most bacterial and viral causes of meningitis can spread from person to person.
Risk factors
Your age, where you live or travel, and certain health conditions can increase your risk of meningitis.
You’re at a higher risk for it if you:
Are under 5 years old or over 65 years old
Have a weakened immune system
Have a CSF leak
Don’t have a spleen
Have chronic nose and ear infections
Have pneumococcal pneumonia
Have alcohol use disorder
Have a brain or spinal cord injury or surgery
Have sickle cell disease
Live in or travel to places where infectious diseases that cause meningitis are common
Live in a group setting, like in a college dorm
Complications of this condition
Complications of meningitis can include:
Hearing or vision loss
Behavioral and thinking issues
Movement issues
Seizures
Increased intracranial pressure
Buildup of fluid in your brain
Damage to the blood vessels in your brain
Sepsis