Meningococcal: The disease and vaccines
Reports of meningococcus in a school or community unleash fear because this bacterial infection can cause death in mere hours. Meningococcus is one of the most rapid and overwhelming infectious diseases known to man:
- About 1 to 2 people in 10 with meningitis caused by meningococcus will die from the infection.
- The number of deaths increases to about 4 in 10 when an infected person gets a bloodstream infection. These bloodstream infections are known as sepsis.
- People can die from sepsis within 12 hours of becoming ill.
The disease
What is meningococcus?
The bacterium, Neisseria meningitidis, can cause illness in anyone, but certain groups are at higher risk. Children younger than 1 year of age are at the greatest risk. While the risk decreases after infancy and throughout early childhood, it increases again during adolescence, the teen years and even early adulthood. Two factors contribute to this increase late in childhood and early in adulthood:
- First, close proximity to new groups of people for extended periods of time, such as at sleepaway camps, the military and college, increases the chance for exposure to new types of bacteria.
- Second, certain activities can increase the risk for exposure or the likelihood that bacteria can get into the bloodstream. Activities like sharing drinks and being intimate can expose individuals to new types of bacteria. Activities like smoking or vaping can disrupt the lining of the throat or lungs, enabling bacteria to enter the bloodstream.
Outbreaks of meningococcus can occur in settings where the bacteria can spread more easily, like childcare centers, schools, colleges and military barracks.
Meningococcus causes different symptoms based on where the infection occurs:
- Meningitis is an inflammation of the lining of the brain. It is the most common outcome of a meningococcal infection. Symptoms of meningitis can include stiff neck, headache, fever and drowsiness.
- Sepsis is an infection of the bloodstream. Symptoms of meningococcal sepsis can include fever, shock and coma.
- Pneumonia is an infection of the lungs.
- Arthritis is an inflammation of joints.
Every year, about 350 people in the U.S. are infected with meningococcus and about 50 die.
About 20 of every 100 survivors experience long-lasting effects like:
- Limb amputation
- Cell death over large areas of skin (often requires grafting, a procedure in which healthy skin is used to cover areas with lost or damaged skin)
- Hearing loss
- Seizures
- Kidney disease
- Intellectual disabilities
About 10 to 15 of every 100 infected people will die from the disease. Immunization is the most effective way to reduce the number of deaths and permanent disabilities caused by meningococcus, especially since the disease can progress too rapidly for treatment to be effective.
How do you catch meningococcal infection?
Meningococcal bacteria spread through intimate contact with an infected person. Intimate contact includes kissing, sharing food or drinks, or staying in the same house or room (including a classroom) for more than four hours a day.
Smoking disrupts the lining of the throat, so people who smoke are at increased risk of some infections, including pneumococcus and meningococcus. Both vaccine-preventable diseases can cause meningitis.
The vaccine
How are the meningococcal vaccines made?
Three types of meningococcal vaccines are available:
- MenACWY - This version has been available for several years and protects against four of the five types of meningococcus (A, C, Y, and W-135).
- MenB - This version is newer and protects against the fifth type of meningococcus, type B.
- MenABCWY – This version combines the MenACWY and MenB vaccines, so a person can be protected against all five types with one vaccine.
MenACWY vaccine
This menACWY vaccine includes the sugar coating of four types of meningococcal bacteria. This sugar coating is called a polysaccharide. For young children to make an immune response, the polysaccharide must be attached to a harmless protein. (see "How Are Vaccines Made?"). When the polysaccharide is attached to the protein, the vaccine is known as a conjugate vaccine. The menACWY vaccine is made similarly to those for pneumococcus and Haemophilus influenzae type b (Hib).
Two menACWY vaccines are commonly used in the U.S.:
- Menveo has been available since 2010 and can be used in people between 2 months and 55 years of age.
- MenQuadfi has been available since 2020 and can be used in people 6 weeks of age and older.
MenB vaccine
The menB vaccine could not be made in the same way that menACWY was made for two reasons:
- First, the sugar coating on meningococcus B is similar enough to a protein in our bodies that using the bacterial coating as the vaccine did not cause robust immune responses. While this is good for us because it shows that our immune systems don’t respond against proteins that they recognize, it made creating a vaccine more difficult.
- Second, meningococcal B had proteins on its surface that could be used to control outbreaks, but they changed from one outbreak to the next.
Because meningococcus type B accounts for two-thirds of meningococcal infections in infants and one-third of meningococcal infections in adolescents and adults, it was important to develop a vaccine against this type of meningococcus. This finally happened in 2015 when two menB vaccines became available — Bexsero and Trumenba. Both vaccines were made using proteins from the surface of the bacteria that could reliably protect against different subtypes of meningococcal B. Trumenba contains two proteins, and Bexsero contains four.
MenABCWY vaccines
Once menB vaccines were available, scientists started work to figure out whether they could be combined with menACWY vaccines, so recipients could be protected against all five types of meningococcus at once. The first menABCWY vaccine, Penbraya, became available in 2023. The second, Penmenvy, became available in 2025.
When people are due for both menACWY and menB vaccines, they can now get menABCWY vaccine. Importantly, because these vaccines contain different menB components, and two doses of menB vaccine are needed, people need to get the same brand even if one of their doses is menABCWY:
- Penbraya and Trumenba have the same menB component (both made by Pfizer).
- Penmenvy and Bexsero have the same menB component (both made by GlaxoSmithKline).
Who should get the meningococcal vaccine?
MenACWY vaccine is recommended for:
- Adolescents and teens 11 to 18 years old
- Children and adults without a spleen or with a spleen that does not function
- Children and adults who lack a particular group of serum proteins that help the body fight infection. These are known as complement proteins and the condition is called a complement deficiency.
- People with human immunodeficiency virus (HIV) infections
- College freshmen living in dormitories
- People exposed during an outbreak if the type is contained in the vaccine (types A, C, Y or W-135)
- Children and adults who will be traveling to sub-Saharan Africa between December and June
- Military recruits
- Lab workers who work with the bacteria
MenB vaccine is recommended for:
- All 16- to 18-year-olds
- Those 18 to 23 years of age who have not previously received it and could benefit
- People aged 10 years and older who have complement deficiencies, no spleen or a spleen that does not function
- Lab workers who work with the bacteria
- People exposed during an outbreak of this type of meningococcus, such as on a college campus
MenABCWY vaccine is recommended for:
- People due for both menACWY and menB vaccines at the same visit
Does the meningococcal vaccine have side effects?
Meningococcal vaccines may cause pain or tenderness where the shot is given, but they do not cause any serious side effects.
Other questions you might have
Is it true that more than one type of infection can cause meningitis?
Yes. Meningitis refers to an infection that has reached the lining of the brain and spinal cord. It can be caused by viruses or bacteria.
Meningitis caused by a virus, called viral meningitis is, the most common type of meningitis. It is often less severe than bacterial meningitis. Vaccine-preventable diseases that can cause viral meningitis, include measles, mumps, chickenpox and influenza.
Bacterial meningitis tends to be more severe. However, most cases of bacterial meningitis can be prevented by vaccination. The bacteria most often associated with meningitis include meningococcus, pneumococcus, and Hib. Most children are fully immunized against pneumococcus and Hib by 2 years of age, and most adolescents are protected against meningococcus.
Find out more about meningitis in this video, “Doctors Talk: Meningitis.”
Should college students get the meningococcal vaccine?
College freshmen who live in dormitories are five times more likely to get a meningococcal infection as compared with those who live off campus or don't attend college. So, both meningococcal vaccines are recommended for all college freshmen living in dormitories.
The risk of meningococcal infection is highest in those younger than 1 year of age, and much lower in those between 4 and 15 years of age. At around 15 years of age, the risk again rises, although not nearly to the level that occurs in infants. Although adolescents and young adults are less likely than infants to be infected, they are more likely to die from the infection, so it is a good idea for all adolescents and teens to be immunized.
Watch this short video to hear why college students should receive meningococcal vaccine.
One of the children in my child's school got bacterial meningitis. Should my child get vaccinated, take antibiotics, or do neither?
In this situation, local public health officials are usually working with school officials and the infected child’s medical team. They will work to find out what bacteria caused the meningitis. This usually takes about 48 hours from the time that the diagnosis was first made. Since other bacteria, such as pneumococcus and Hib, can also cause meningitis, this is important to know. If the cause was meningococcus, find out from public health officials whether it is considered an outbreak or if it is an isolated case. This will help in determining whether your child should be vaccinated, treated or both.
If the case is part of an outbreak caused by meningococcus, your child should be vaccinated with a version of the vaccine that contains the type of meningococcus involved in the outbreak.
In addition, antibiotics are likely to be prescribed for all children who have come in close contact with the infected person. Close contact is defined as sharing a classroom for more than four hours a day, kissing, or sharing food or drinks.
The timing will also be considered in determining next steps. Close contact in the week prior to the outbreak increases a person’s risk of infection.
Relative risks and benefits
Do the benefits of the meningococcal vaccine outweigh its risks?
Each year, about 350 people in the U.S. are infected with meningococcus and about 50 die. Some survivors suffer permanent disabilities, such as seizures, loss of limbs, kidney disease, deafness, death of skin cells requiring grafting or intellectual disabilities.
Meningococcal vaccines do not cause any severe reactions.
Therefore, the benefits of meningococcal vaccination outweigh the risks.
Disease risks
- Meningitis, an inflammation of the lining of the brain.
- Sepsis, an infection of the bloodstream.
- About 15 to 20 of every 100 survivors will suffer lifelong effects, such as limb amputation, skin cell death requiring grafting, hearing loss, seizures, kidney disease and intellectual disabilities.
- Disease can be fatal (10 to 15 of 100 people).
Vaccine risks
- Pain or tenderness at the injection site
References
Plotkin SA, Orenstein W, Offit PA, and Edwards KM. Meningococcal capsular group A, C, W, and Y conjugate vaccines in Vaccines, 8th Edition, 2024, 664-689.
Plotkin SA, Orenstein W, Offit PA, and Edwards KM. Meningococcal vaccines directed at capsular group B in Vaccines, 8th Edition, 2024, 690-710.
Reviewed by Paul A. Offit, MD, on February 18, 2026