Meningococcal Infections

Most people with a meningococcal infection feel very ill.

Meningitis often causes fever, headache, red rash, and a stiff neck. It can also cause nausea, vomiting, and sensitivity to light.

Infants may have feeding problems and a weak cry, and they may be irritable and sluggish.

Bloodstream infections Bacteremia Bacteremia is the presence of bacteria in the bloodstream. Bacteremia may result from ordinary activities (such as vigorous toothbrushing), dental or medical procedures, or from infections ... read more may cause a rash of red or purple spots. A severe infection may cause dangerously low blood pressure (shock), a tendency to bleed, and dysfunction (failure) of many organs (such as the kidneys and liver).

Rarely, meningococcal infection causes a chronic illness that causes mild, recurring symptoms that mostly involve the joints and skin.

Doctors suspect meningococcal infection in people who have typical symptoms, particularly if symptoms occur during an outbreak.

To confirm the diagnosis, doctors take samples of blood or other infected tissues or do a spinal tap Spinal Tap Diagnostic procedures may be needed to confirm a diagnosis suggested by the medical history and neurologic examination. Imaging tests commonly used to diagnose nervous system (neurologic) disorders... read more (lumbar puncture) to obtain a sample of the fluid that surrounds the brain and spinal cord (cerebrospinal fluid). The samples are examined under a microscope to check for and identify bacteria. The samples are also sent to a laboratory, where the bacteria can be identified after it is grown (cultured) or other laboratory tests are done.

If the bacteria is difficult to culture or other test results are inconclusive, doctors can do tests to identify pieces of the bacteria’s genetic material. Tests that detect genetic material in microorganisms are called nucleic acid–based tests. Polymerase chain reaction (PCR) is an example of this type of test. The PCR technique is done on samples of cerebrospinal fluid, blood, or other infected tissues. It is used to produce many copies of a gene from the bacteria, making the bacteria much easier to identify.

Sometimes doctors do blood tests that detect antibodies to the bacteria or the capsule that encloses the bacteria. However, the results have to be confirmed by culture.

The bacteria may also be tested to determine which antibiotics are effective (a process called susceptibility testing Testing a Microorganism's Susceptibility and Sensitivity to Antimicrobial Drugs Infectious diseases are caused by microorganisms, such as bacteria, viruses, fungi, and parasites. Doctors suspect an infection based on the person's symptoms, physical examination results,... read more ).

Overall, 4 to 6% of people who have meningococcal meningitis die. Up to 40% of people with severe meningococcal bloodstream infections and septic shock die.

Of people who recover from meningococcal meningitis, 10 to 20% have serious complications, such as permanent hearing loss, intellectual disability, or seizures. Complications of bloodstream infections include gangrene of the fingers, toes, or limbs, which may require amputation.

People are usually admitted to an intensive care unit and given antibiotics and fluids intravenously as soon as possible, before doctors get the culture results identifying the organism causing the infection.

If meningococci are confirmed, doctors change the antibiotics to those that tests show are most effective against the bacteria, typically ceftriaxone or penicillin. These drugs are given intravenously.

Corticosteroids (such as dexamethasone) may be given to children and adults who have meningitis. These drugs help prevent brain damage.

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

See the following government sites for comprehensive information on everything from updates on outbreaks and risk factors to educational materials and quick links to related topics: