How contagious is meningitis?

While meningitis itself is not contagious, the pathogens causing it can be transmitted from person to person. The type of transmission, e.g. via air, saliva, contact, sexual intercourse or ticks, depends on the respective pathogens. Often these pathogens are initially responsible for another clinical picture and only later lead to the development of meningitis.

An infection with the pathogens without developing clinical symptoms is also possible. Some viruses and bacteria are transmitted via small secretion droplets that originate from the human respiratory tract and saliva and are taken up by other people via breathing (droplet infection). These are a large number of pathogens that cause meningitis, including herpes viruses, meningococcus, pneumococcus and Haemophilus influenzae. Other viruses and bacteria are transmitted via ticks and are therefore not contagious from person to person (e.g. Borrelia, TBE virus). Many other forms of infection are possible.

How dangerous is meningitis?

Meningitis can have a severe course, especially if the patient is infected with bacteria. The prognosis depends on the patient’s general condition, immune system and age. The earlier a therapy with antibiotics is started, the sooner serious and sometimes life-threatening consequences for the patient can be avoided.

If the inflammation spreads to the brain tissue, many neurological disorders and failures are possible. Disturbances of consciousness, a general restlessness, seizures and hearing disorders can occur. In extreme cases, paralysis may also occur.

A dreaded complication of meningitis is the Waterhouse-Friedrichsen syndrome. It occurs mainly in untreated infections with the bacterium ‘meningococcus’. The spread of the bacterium via the bloodstream throughout the body (sepsis) causes severe damage to the blood clotting system. A failure of several organs is possible. The Waterhouse-Friedrichsen syndrome mainly affects small children and young adults in whom the immune system is not yet fully developed.

Diagnosis

The suspected diagnosis is made after the patient presents one or more symptoms that would be typical of meningitis. Patient interviewing is also important. For example, the patient should always be asked about recent long-distance travel or stays in meningitis areas or whether a tick bite was present in the past.

Also the sudden active bending in the knee with passive bending of the head is one of the meningitis signs with urgent suspicion of this disease. If these so-called meningitis signs are positive, a neurological examination of the patient is urgently required. Usually in the hospital a detailed blood count is then made.

Especially the inflammation values, such as CRP or leukocytes are important. A massive increase increases the suspected diagnosis of meningitis. The next diagnostic measure is the examination of the cerebral fluid, the so-called liquor puncture.

It may only be carried out after an increased cerebral pressure has been ruled out. This is done with a mirror image of the back of the eye. If the optic nerve is curved forward, an increased intracranial pressure is to be assumed, which prohibits the cerebrospinal fluid puncture. If the optic nerve is normal, CSF puncture can be performed.