Meningococcal B vaccine - what you need to know

The meningococcal B vaccine, often called the MenB vaccine, protects against group B Neisseria meningitidis. This bacterium can sometimes cause meningitis, which is inflammation around the brain and spinal cord, or a serious bloodstream infection.

MenB vaccine does not contain live meningococcal bacteria. It cannot cause meningococcal disease. It trains your immune system to recognize proteins found on group B bacteria.

MenB is separate from the MenACWY vaccine. MenACWY protects against meningococcal groups A, C, W, and Y. Receiving one type does not replace the other.

In the United States, healthy people ages 16 through 23 may receive MenB vaccination after discussing their individual risk and preferences with a clinician. The preferred age is usually 16 through 18, when the risk is higher than in younger adolescents.

MenB vaccination is also recommended from age 10 for people at increased risk. This includes people who:

• Have a damaged or missing spleen, including reduced spleen function
• Have certain immune conditions affecting proteins called complement
• Take complement-blocking medicines, such as eculizumab or ravulizumab
• Work with meningococcal bacteria in a laboratory
• Are identified as at risk during a group B outbreak

Recommendations and licensed age ranges can differ by country. Public health officials may also give specific advice during an outbreak.

MenB vaccines contain selected bacterial proteins rather than whole bacteria. After vaccination, your immune system produces antibodies. These proteins in the blood can help recognize and attack group B meningococcal bacteria before they cause invasive infection.

Protection is not immediate. Your immune system needs time after each dose to respond. Completing the recommended series provides better protection than receiving only part of it.

In the United States, the two main MenB vaccine products are Bexsero and Trumenba. Their ingredients and schedules are not identical. Doses in a series should come from the same product whenever possible.

For healthy adolescents and young adults choosing vaccination, the usual schedule is two doses given six months apart. A three-dose schedule may be used when faster protection is wanted.

People at increased risk generally receive three doses: the first dose, another one to two months later, and a third six months after the first. Timing can require adjustment if a dose was given early, so keep an accurate vaccination record rather than trying to calculate the schedule yourself.

People whose increased risk continues may need a booster one year after completing the main series, followed by boosters every two to three years. Public health officials may recommend boosters on a different timeline during an outbreak.

Meningococcal disease is uncommon, but it can become serious quickly. Adolescents and young adults have a higher risk than many other age groups. Certain immune conditions, medicines, laboratory work, and outbreaks increase risk further.

Vaccination lowers the chance of group B meningococcal disease. It does not protect against every meningococcal group or every possible group B strain, and no vaccine provides complete protection.

Your likely benefit depends on your age, medical history, medicines, living situation, and whether there is an outbreak. For a healthy young person, MenB vaccination is usually a shared decision rather than a universal requirement. Factors such as living in close-contact settings, personal concern about the disease, or plans affected by an outbreak may be part of that discussion.

College vaccine requirements do not always include MenB. Many requirements refer specifically to MenACWY. Check which vaccine is named rather than assuming one meningococcal vaccine covers all groups.

The most common problems are short-term vaccine reactions. These can include pain, redness, or swelling where the injection was given. Some people develop tiredness, headache, muscle or joint pain, nausea, chills, or fever.

These effects usually settle within a few days. Rest, fluids, and normal use of the arm may help. Ask a pharmacist or clinician before taking medicine for pain or fever if you have allergies, health conditions, take other medicines, or are unsure what is suitable.

Fainting can happen after injections, especially in adolescents. Sitting or lying down during vaccination and remaining under observation afterward can reduce the chance of injury from a fall.

A severe allergic reaction is rare but requires emergency care. Call emergency services for difficulty breathing, swelling of the face or throat, widespread hives, severe weakness, or collapse after vaccination.

Tell the vaccination service before a dose if you had a severe allergic reaction to an earlier MenB dose or a vaccine ingredient. If you are moderately or severely unwell, the service may advise waiting until you recover. A mild illness, such as a minor cold, often does not require a delay.

Another problem is assuming that vaccination rules out meningococcal disease. Seek emergency medical care for possible meningitis or bloodstream infection, even if you have been vaccinated. Warning signs can include a sudden fever with severe headache, stiff neck, confusion, unusual sleepiness, repeated vomiting, rapid breathing, cold hands and feet, or a dark red or purple rash that does not fade when pressed. Do not wait for every sign to appear.

Check your vaccine record for the product name, dose dates, and whether you received MenB or MenACWY. A school form that says “meningococcal vaccine” may not make this distinction clear.

Ask a primary care clinician, pharmacist, or vaccination service:

• Whether your age, health, medicines, work, or outbreak exposure raises your risk
• Whether MenB vaccination is recommended or an optional shared decision
• Which product you previously received
• How many doses remain and when they are due
• Whether you need boosters because your increased risk continues

If you missed a dose, do not assume that the series must be restarted. Bring your record to a vaccination service so the next dose and timing can be checked.

If you are pregnant, tell the vaccination service. MenB vaccination may be delayed when there is no immediate increased risk because pregnancy safety data are limited. If you are at increased risk, a clinician can help weigh the known threat of exposure against the available vaccine information.

After vaccination, routine soreness or tiredness can usually be monitored at home. Contact a clinician if a reaction is getting worse, is not settling, or concerns you. Use emergency services for signs of a severe allergic reaction or possible meningococcal disease.

Can MenB vaccine cause meningitis?

No. MenB vaccines do not contain live meningococcal bacteria and cannot cause meningococcal infection.

Do I need MenB if I already received MenACWY?

Possibly. The vaccines protect against different groups of meningococcal bacteria. Receiving MenACWY does not provide group B protection.

Can MenB vaccine be given with other vaccines?

It can generally be given during the same visit as other vaccines. The injections are placed at different sites. Your vaccination service should record each product separately.

What if I cannot remember which MenB product I received?

Ask the clinic, pharmacy, school health service, or immunization registry that may hold the record. The same MenB product should be used for all doses when possible. If the product cannot be confirmed, a clinician can determine how to proceed.

Will I need a booster?

Healthy people vaccinated through shared decision-making do not usually receive routine MenB boosters. Boosters are recommended for people whose increased risk continues and may be advised during an outbreak.

Does everyone going to college need it?

Not necessarily. Requirements differ between colleges, housing programs, and locations. Check whether the requirement names MenB, MenACWY, or both.