Is an inflammation of the brain contagious?
In Germany, most brain inflammations are caused by viruses. In addition to herpes viruses, these include the TBE viruses (early summer meningo-encephalitis viruses), mumps viruses, measles viruses, rubella viruses and many others. In themselves, all these viruses are primarily contagious.
However, it is important to know that an infection does not necessarily lead to encephalitis. For most adults, an infection with normal herpes zoster viruses, for example, is largely harmless. Especially small children and people with a pronounced immune deficiency have an increased risk of developing encephalitis as a result of an infection. If these risk groups come into contact with sick people, certain protective measures should therefore be taken.
Prognosis
The course of an inflammation in the brain depends on the patient’s age and state of health. In immunocompromised patients, the course of the disease is often fatal. The prognosis for bacterially caused meningitis is only favorable if a diagnosis is made as quickly as possible.
If the pathogens come into contact with the central nervous system via the bloodstream or through an injury, the chances for the patient to recover from the disease are better than if the pathogens were transmitted after previous infection of the nose or ears. Pneumococcal-induced inflammation (30% mortality rate) is usually poor in adults, in contrast to meningococcal infections (5% mortality rate). The faster the symptoms develop and the more complications arise during the course of the disease (e.g. heart failure), the worse the prognosis is generally.Inflammations in the brain become dangerous at particularly low or high age.
The mortality rate is highest in infants with E. coli meningitis, but infections caused by other pathogens are also more dangerous than in adult patients. The consequences of meningitis may include paralysis of the eye muscles, hydrocephalus occlusus, deafness (in half of all pneumococcal meningitis cases) or epileptic seizures. The prognosis for encephalitis is positive in the majority of cases.
Milder symptoms favour a complete cure. Herpes simplex encephalitis and encephalitis in HIV-infected persons are exceptions. The brain swelling caused by Herpes simplex is the most common cause of death in infections and a quarter of patients suffer severe permanent damage, such as mental disorders, paralysis or blindness. AIDS patients almost always develop neurological or psychological involvement in the late stages of their disease. Infections with other pathogens, which can attack through the weakened immune system, also play an important role.