Subacute sclerosing panencephalitis (SSPE) is a brain disorder. It progresses and is typically fatal. An abnormal reaction by your immune system to the measles virus, or rubeola, is likely the cause. It causes inflammation, swelling, and irritation of your brain. It may occur years after you recover from the measles.

SSPE is a rare disease. It usually occurs in children and adolescents, and it’s more common in males than females. In the Unites States, where young children routinely receive the measles vaccine, the incidence of SSPE is less than 10 per year, reports the National Institute of Neurological Disorders and Stroke (NINDS). In countries that lack standard immunization programs, the incidence is higher. Immunization against the measles virus is the only way to prevent SSPE.

If you contract the measles, you won’t necessarily develop SSPE. In fact, most people who get the measles never develop SSPE. Experts are still studying why SSPE develops. Many believe that it’s caused an abnormal immune response to the measles virus or possibly mutated forms of the virus.

If you develop SSPE, you may experience:

  • gradual changes in your behavior
  • unusual behavior
  • a decrease in your cognitive and social abilities
  • difficulty completing schoolwork or work
  • dementia
  • lethargy
  • muscle spasms or jerking
  • tense or lax muscles
  • weakness in both legs
  • an unsteady gait
  • seizures
  • a coma

If you’re experiencing seizures, you need to take precautions to avoid injuries that may occur during them.

After asking about your medical history, your doctor will check for the following signs of SSPE:

  • damage to your optic nerve
  • damage to the retinas in your eyes
  • muscle twitching
  • poor performance on movement and coordination tests

Your doctor may also request additional tests or procedures, such as:

  • an electroencephalogram
  • an MRI
  • a spinal tap
  • a serum antibody titer, which is a blood test to check for a previous measles infection

No cure is available for SSPE. However, your doctor can prescribe some antiviral drugs that may slow the progression of your condition. They may also prescribe anticonvulsant drugs to control seizures. According to NINDS, most people with SSPE die within one to three years. In some cases, they live longer.

The only way to prevent SSPE is to get the measles vaccine. According to the World Health Organization, the measles vaccine has been available for 50 years. It’s effective, safe, and inexpensive. The organization recommends immunizing all children with two doses of the measles vaccine, either alone or in a measles-mumps-rubella or a measles-rubella combination. Unimmunized adults should also be immunized.

If you haven’t received the immunization, ask your doctor about the measles vaccine. In addition to preventing SSPE, it can also help you avoid contracting measles. The measles virus can cause:

  • diarrhea
  • pneumonia
  • inflammation of your brain

Measles can even cause death. Getting the vaccine is a simple and safe way to keep yourself safe.