Encephalitis vs Meningitis: Differences

People with very mild encephalitis or meningitis can make a full recovery

Encephalitis is an inflammation of the brain tissue. Its symptoms include:

• Fever
• Headache
• Muscle aches
• Fatigue
• Drowsiness
• Confusion
• Seizures
• Paralysis
• Personality changes (very common)
• Sudden severe dementia (memory loss)
• Ataxia (unable to balance oneself)

Meningitis is an inflammation of the coverings (meninges) of the brain and the spinal cord. Symptoms of meningitis include:

• Fever
• A sudden severe headache
• Neck stiffness
• Nausea
• Vomiting
• Decreased appetite
• Photosensitivity (sensitivity to light)
• Confusion
• Drowsiness

Both encephalitis and meningitis are most often caused by a virus. Meningitis can be caused by bacteria, fungi, and parasites as well, but these are less common.

The viruses that cause meningitis include the influenza virus, mumps, measles virus, and herpes virus.. 

Encephalitis can be autoimmune encephalitis as well. The inflammation in autoimmune encephalitis is caused by the attack of healthy cells of the body by the body’s immune system. Meningitis caused by an autoimmune component is not yet reported.

Encephalitis can also be caused by arboviruses—types of viruses that are transmitted through the bites of ticks and mosquitoes. Types of such encephalitis include West Nile virus, Eastern equine, and rabid (caused by rabies) encephalitis.

Apart from the medical history, signs, and symptoms, diagnosis of meningitis and encephalitis requires:

• Neurological examination
• Blood tests
• Imaging tests such as computerized tomography scan or magnetic resonance imaging
• Examination of cerebrospinal fluid (a fluid present in the brain and spinal cord)

Encephalitis may require additional tests for its diagnosis. These include:

• Electroencephalography (placing of electric, metal discs on your head to measure the electrical activity in your brain)
• Brain biopsy (surgical removal of brain tissue for examining it under a microscope)

Encephalitis and meningitis are life-threatening conditions that require you to be hospitalized immediately. 

The treatment of bacterial forms of meningitis and encephalitis involves a course of antibiotics. 

The antivirals may be started by the doctor for viral encephalitis. The medication for control of fits and dexamethasone to control brain swelling may be given.

Viral meningitis can be treated with antiviral and antiinflammatory medications.

The vaccine against measles, mumps, and rubella (MMR vaccine) has been seen working against encephalitis. But there is no vaccine against encephalitis caused by ticks. Though not available in the United States, it is available in Europe and Canada. The vaccine is advised for people who travel to those European regions, where tick-borne encephalitis is prevalent.

Several vaccines are available against meningitis. These include:

• Pneumococcal vaccine
• Meningococcal vaccine
• Influenza vaccine 
• MMR vaccine 

To avoid mosquito- or tick bites, people should

• Restrict outdoor activities at night.
• Wear long-sleeved clothing when outdoors.
• Use insect repellents. 
• Get rid of stagnant water lying in the lawn areas.

The time required to recover from encephalitis and meningitis depends on: 

• The type of microbe
• The severity of the disease
• How quickly treatment is given

People with very mild encephalitis or meningitis can make a full recovery, although the process may be slow. Extremely severe cases may result in fatalities. Individuals with mild symptoms may recover in 15-30 days. The acute phase of encephalitis with severe symptoms may last for one to two weeks, with a gradual or sudden resolution of fever and neurological symptoms over the next few weeks. Individuals treated for bacterial meningitis typically show improvements in two to three days, though full recovery takes time. In serious cases, these diseases can cause permanent hearing loss, speech loss, blindness, memory loss, a decline in mental abilities, and seizures. Physical therapy and rehabilitation may be needed in many people to tackle residual damage to the body parts. The mortality rates differ from 20 to 75% depending on the offending organism and whether the encephalitis was treated on time or left untreated.