Meningitis B is a bacterial infection that causes inflammation around the brain and spinal cord. Without early treatment, it can lead to serious complications.

Meningitis B is a rare but serious illness caused by Neisseria meningitidis group B bacteria. This bacterium can lead to meningitis, an infection that causes inflammation in the protective membranes and fluid surrounding the brain and spinal cord.

In some cases, the bacteria can also cause other severe conditions, such as blood poisoning (septicemia), which can be life threatening.

Without prompt treatment, meningitis B can lead to serious complications, including hearing loss, limb amputation, or death. Even with treatment, some people experience lasting effects.

Read on to learn about meningitis B, including symptoms to watch for and ways to reduce your risk.

Meningitis B, more often referred to as meningococcal meningitis, is caused by the Neisseria meningitidis (N. meningitidis) bacterium. This bacterium has several subtypes known as serogroups.

In the United States, serogroup B is one of the leading causes of serious meningococcal infections, including meningitis and bloodstream infections.

Over 50 types of bacteria can cause meningitis. It can also be caused by:

  • viral infections
  • fungal infections
  • parasitic infections (although this is rare)

Viruses and bacteria are the most common causes. Viral meningitis is typically milder than meningitis B and usually resolves on its own.

Once contracted, the bacteria responsible for meningitis B typically enter the bloodstream, where they can travel to the brain and spinal cord. This can lead to swelling in the protective membranes (meningitis) and, in some cases, a serious bloodstream infection known as septicemia.

While uncommon, meningitis B can become life threatening within 24 hours.

The symptoms of meningitis B tend to come on quickly, usually within a week after exposure. In the early stages, symptoms can resemble the flu, which may delay diagnosis and treatment.

Meningitis B progresses rapidly, so it’s important to seek emergency medical care if you have any of the following symptoms:

You should also talk with a doctor if you’ve been in close contact with someone who has meningitis B, even if you don’t have symptoms yet.

In children, teens, and adults, symptoms may include:

In babies and toddlers, additional symptoms may occur, including:

Seek immediate medical care if your baby or child shows any of these symptoms.

Meningitis B isn’t spread through casual, brief contact or by touching infected surfaces. Instead, it spreads through respiratory droplets, like when someone coughs, sneezes, or kisses another person.

Certain behaviors and health factors can increase your risk of infection, including:

  • living in close quarters, such as in dorms or shared spaces
  • kissing or having close, prolonged contact with someone who carries the bacteria
  • recent smoking or exposure to secondhand smoke
  • having a recent respiratory infection, such as a cold or the flu

Anyone can get meningitis B, but certain groups are at a higher risk, including:

  • infants younger than 1 year
  • adolescents and young adults ages 16 to 23 years
  • people who live in dormitories or other shared housing
  • people who have weakened immune systems

Practicing good hygiene and avoiding close contact with people who have the infection can help lower your risk of meningitis B. Other preventive steps include:

  • frequent handwashing
  • avoiding smoking
  • not sharing utensils, water bottles, or items that touch your mouth

Meningitis B vaccine

The most effective way to protect against N. meningitidis, the bacteria that cause meningitis B, is by getting vaccinated. There are three types of meningococcal vaccines available:

  • MenACWY vaccines: protect against serogroups A, C, W, and Y
  • MenB vaccines: protect against serogroup B
  • pentavalent MenABCWY vaccines: protect against all five major serogroups in one shot

MenACWY (MCV4)

This meningococcal conjugate vaccine protects against serogroups A, C, W, and Y. It’s typically recommended for children at age 11 or 12, with a booster given at around age 16.

If your child has a medical condition that increases their risk, they may need a booster every 5 years. Healthcare professionals also recommend a booster if a meningitis outbreak occurs more than 5 years after the child’s last shot.

Like all vaccinations, those for meningitis B may have some side effects, including:

  • swelling or tenderness at the injection site
  • mild fever

MenB vaccine

The MenB vaccine protects against meningococcal disease caused by serogroup B. It’s approved for people ages 10 years and older and recommended for those at higher risk, including people who:

  • have certain medical conditions like sickle cell disease or a damaged or missing spleen
  • have immune system conditions that affect complement properties in the immune system
  • take complement inhibitor medications, like eculizumab (Soliris) or ravulizumab (Ultomiris)
  • live in or travel to areas experiencing a meningitis B outbreak

Healthy teens and young adults ages 16 to 23 may also choose to get the vaccine after talking with a healthcare professional. The preferred age for vaccination is 16 to 18 years. In some high risk situations, healthcare professionals may recommend booster shots every 2 or 3 years.

There are two MenB vaccines available:

  • Bexsero is a two-dose series, given at least 1 month apart.
  • Trumenba is a two-dose series typically given 6 months apart. If a child gets the second dose early, they may need a third dose.

Possible MenB vaccine side effects include:

  • pain or swelling at the injection site
  • fever
  • headache
  • chills
  • nausea
  • diarrhea
  • fatigue
  • muscle aches

Pentavalent MenABCWY vaccine

The pentavalent meningococcal vaccine protects against all five major serogroups of Neisseria meningitidis (A, B, C, W, and Y) in a single shot. It provides protection offered by the MenACWY and MenB vaccines.

Doctors may recommend it for people ages 10 to 25 who need both types of meningococcal vaccines. This includes individuals with certain high risk health conditions or people exposed during an outbreak.

The preferred age for the MenABCWY vaccine is ages 16 to 18 years, but anyone between 16 and 23 can receive it based on a doctor’s recommendation.

The vaccine is currently available under the brand name Penbraya.

Possible side effects are similar to other meningococcal vaccines and may include:

  • pain or swelling at the injection site
  • fever
  • headache
  • fatigue
  • muscle aches

Meningitis B is a medical emergency and requires immediate hospital care. Treatment typically begins with an injection of broad-spectrum antibiotics to fight the infection as quickly as possible. You may also receive intravenous (IV) fluids to prevent dehydration and support recovery.

If you’re having trouble breathing, you may need oxygen.

To help prevent the spread, people who have been in close contact may also receive a short course of oral antibiotics as a precaution.

With prompt treatment, most people who develop this disease recover without long-term complications. However, meningitis B can be life threatening and may progress quickly, sometimes within a few hours.

Even with medical care, some people don’t survive. Early treatment offers the best chance for a full recovery.

Among those who do survive, about 1 in 5 experience lasting effects, which can include:

Meningitis B is a serious bacterial infection that can lead to life threatening complications and long-term health issues.

While it can affect people of all ages, young adults, especially those living in close quarters like dorms, are at a higher risk.

Getting vaccinated is the best protection against meningitis B. To stay fully protected against all major meningococcal disease strains, healthcare professionals typically recommend two different vaccines: one for serogroups A, C, W, and Y, and another for serogroup B.

If you or your child may be at risk, talk with a healthcare professional about the best time to get vaccinated.