Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Meningococcal Infections

By

Larry M. Bush

, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University

Last full review/revision Jul 2020| Content last modified Jul 2020
Click here for the Professional Version
Topic Resources
  • Infection is spread by direct contact with nasal and throat secretions.

  • People feel generally ill and have other, often serious symptoms, depending on the area infected.

  • Identifying the bacteria in a sample taken from infected tissue confirms the diagnosis.

  • Vaccination can help prevent meningococcal infections.

  • Antibiotics and fluids must be given intravenously as soon as possible.

More than 90% of meningococcal infections are

Infections of the lungs, joints, eyes, and heart are less common.

In temperate climates, most meningococcal infections occur during winter and spring. Local outbreaks can occur, most often in sub-Saharan Africa between Senegal and Ethiopia. This area, which includes 26 countries, is known as the meningitis belt.

Meningococci reside in the throat and nose of some people without causing symptoms. Such people are called carriers. People often become carriers after outbreaks. However, infection usually occurs in people who have not been exposed previously to meningococci, rather than in carriers. Infection is spread by direct contact with nasal and throat secretions of an infected person (including carriers).

Most commonly infected are

Infections are also common among

Meningococcal disease is more common among people with AIDS than among the general population. Other factors that may increase risk include getting a viral infection, living in a crowded household, having a chronic illness, and smoking or being exposed to cigarette smoke (passive smoking).

Outbreaks account for only a small percentage of cases and tend to occur among people who spend time or live in close quarters with others, for example, in dormitories or day care centers, and often involve people 5 to 19 years of age.

Symptoms of 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.

Diagnosis of Meningococcal Infections

  • Examination and culture of samples of blood or other infected tissues, including cerebrospinal fluid obtained by spinal tap

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. Electroencephalography (EEG) is a simple, painless procedure in which... read more Spinal Tap (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.

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.

Prognosis of Meningococcal Infections

Overall, 10 to 15% of people who have meningococcal infections die. Up to 40% of people with severe bloodstream infections die. Of people who recover, 10 to 20% have serious complications, such as permanent hearing loss, intellectual disability, seizures, or gangrene of the fingers, toes, or limbs, which may require amputation.

Prevention of Meningococcal Infections

After exposure to meningitis

Family members, medical personnel, and other people in close contact with people who have a meningococcal infection should be given an antibiotic to prevent infection from developing. Antibiotics may be given by mouth or by injection. With most recommended antibiotics, only a single dose or at most 2 days of treatment are needed.

During an outbreak, meningococcal vaccine is also given (in addition to antibiotics) to people in close contact with a person who has a meningococcal infection.

Vaccination

Meningococcal vaccines protect against specific types (called serogroups) of meningococci that cause most meningococcal disease: serogroups A, B, C, W, and Y.

  • MenACWY vaccines: These vaccines protect against meningococcal serogroups A, C, W, and Y. They are part of the routine childhood vaccination schedule and are recommended for all children at age 11 to 12 years, with a booster at age 16 years.

  • MPSV4: This vaccine is given only to certain people over age 55 years.

  • MenB vaccines: These vaccines protect against meningococcal serogroup B, which is a type of meningitis bacteria that has become common in outbreaks among college students.

Meningococcal vaccine is also recommended for the adolescents and adults who are at increased risk of meningococcal infection.

Treatment of Meningococcal Infections

  • Antibiotics given by vein (intravenously)

  • Fluids given intravenously

  • Possibly corticosteroids

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 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.

More Information

The following are English-language resources that 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:

Drugs Mentioned In This Article

Generic Name Select Brand Names
OZURDEX
ROCEPHIN
Ravulizumab
SOLIRIS
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Test your knowledge

Dengue
Dengue is a viral infection that causes fever, aches throughout the body, and, in severe cases, bleeding in multiple areas. How is the dengue virus transmitted? 
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
TOP