Meningococcal Disease Tests

What is a meningococcal disease test?

Meningococcal disease is the name for any infection caused by meningococcal bacteria (called Neisseria meningitidis). Meningococcal disease tests look for these bacteria in your blood or cerebrospinal fluid (CSF), the fluid in spaces around your brain and spinal cord.

Meningococcal disease can be spread from person to person by coming into contact with someone's respiratory secretions (saliva) or throat secretions (spit). The bacteria aren't as contagious as germs that cause the common cold or the flu. For the bacteria to spread, it takes close contact (kissing) or lengthy contact (living together).

The most common signs and symptoms of meningococcal disease are a sudden high fever, neck stiffness, confusion, nausea, vomiting, fatigue, and rash. Diagnosing meningococcal disease can be difficult because the signs and symptoms are often similar to other illnesses. If not treated early and with the right type of treatment, meningococcal infection can get worse quickly and cause death.

If your health care provider thinks you might have meningococcal disease, they will order one or more of these meningococcal disease tests:

• Meningococcal culture test, a bacterial culture test that helps find meningococcal bacteria in a sample of your blood or CSF. Your sample will be sent to a lab where the bacteria cells will be put in a dish with a special substance that lets the bacteria grow.
• Meningococcal polymerase chain reaction (PCR) test, a test that checks for small amounts of the genetic material of meningococcal bacteria in a sample of your blood or CSF.
• Meningococcal antigen test, a test that looks for antigens (proteins from a foreign substance that trigger your immune system to fight it off) specific to the meningococcal bacteria.

The two most common types of meningococcal infections are meningitis and bloodstream infections.

• In meningococcal meningitis, the lining of the brain and spinal cord become infected by the bacteria, which causes inflammation (swelling).
• In meningococcal bloodstream infections, the bacteria get into the blood and cause damage to the walls of the blood vessels, which causes bleeding in the skin and organs.

Anyone can get meningococcal disease, but some people have a higher risk. This includes those who:

• Travel outside of the U.S. to areas where meningococcal disease is common
• Are younger than one year old
• Are teenagers and young adults ages 16-23 years old
• Are an adult aged 65 years and older
• Have a medical condition that weakens the immune system such as HIV, having no spleen or an injured spleen, or a disorder of the complement system, which helps the body fight infections
• Live in close quarters with many other people like on a college campus or military base
• Take a type of medicine called a complement inhibitor, which is used to treat certain rare diseases

Other names: Neisseria meningitidis Tests, N. meningitidis Tests

What is it used for?

Meningococcal disease tests are used to find out whether you have meningococcal disease.

Why do I need a meningococcal disease test?

Meningococcal meningitis and bloodstream infections are serious and can become deadly in a matter of hours. It's important to seek medical attention immediately and get the right diagnosis and treatment to help prevent serious health problems.

Symptoms are different for meningococcal meningitis and bloodstream infections.

The most common symptoms of meningococcal meningitis for adults include:

• Fever
• Headache
• Stiff neck

Additional symptoms of meningitis for adults include nausea, vomiting, light sensitivity, and confusion.

The most common symptoms of meningococcal meningitis for babies include:

• Appearing slow or inactive
• Irritability
• Feeding poorly
• Having a soft spot on the skull
• Having abnormal reflexes
• Vomiting

The most common symptoms of a meningococcal bloodstream infection in adults include:

• Cold hands and feet
• Diarrhea or nausea without vomiting
• Fatigue
• Fever and chills
• Rapid breathing
• Severe aches or pain in the muscles, joints, chest, or abdomen (belly)
• Dark, purple rash (in the later stages)

Call your provider right away if you think you or your child might have meningococcal disease.

What happens during a meningococcal disease test?

Your provider will take samples from your blood and may also take a sample from your CSF to do a spinal tap (lumbar puncture) to check for the Neisseria meningitidis bacteria in your body. These samples will then be sent to a laboratory to test for meningococcal disease and figure out which antibiotic will work best for treatment.

If the meningococcal bacteria are in the samples, the laboratory will be able to culture (grow) them using the meningococcal culture test. If it's not clear from this test whether your samples have the meningococcal bacteria in them, your provider may order additional tests such as the meningococcal antigen test or PCR test.

During a blood test:

If your provider thinks you might have a meningococcal infection, they may collect a blood sample for a meningococcal culture test, PCR test, or antigen test.

A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

During a spinal tap:

If your provider thinks you might have a meningococcal infection, they may collect a CSF sample for a meningococcal culture test, PCR test, or antigen test.

To get a sample of CSF, a provider will do a procedure called a spinal tap, also known as a lumbar puncture. A spinal tap is usually done in a hospital. During the procedure:

• You will lie on your side or sit on an exam table.
• Your provider will clean your back and inject an anesthetic into your skin, so you won't feel pain during the procedure. They may put a numbing cream on your back before this injection.
• When the area on your back is completely numb, your provider will insert a thin, hollow needle between two vertebrae in your lower spine. Vertebrae are the small backbones that make up your spine.
• Your provider will withdraw a small amount of cerebrospinal fluid for testing. This will take about five minutes.
• You'll need to stay very still while the fluid is being withdrawn.
• Your provider may ask you to lie on your back for an hour or two after the procedure. This may prevent you from getting a headache afterward.

Will I need to do anything to prepare for this test?

Talk to your provider and ask about any special preparations. You may need to fast (not eat or drink) before the test. You may also need to stop taking certain medicines, so be sure to tell your provider about everything you take. But don't stop taking any medicines unless your provider tells you to.

Are there any risks to this test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

With a spinal tap, there is very little risk. You may feel a little pinch or pressure when the needle is inserted. After the test, you may feel some pain or tenderness in your back or have some bleeding where the needle was inserted. You may also get a headache. The headache may last for several hours or up to a week or more, but your provider may suggest treatment to relieve the pain.

What do the results mean?

The results will show whether you have meningococcal disease.

• A positive result means that meningococcal bacteria (Neisseria meningitidis) were found in your blood or CSF sample. You most likely have meningococcal disease.
• A negative result means that no meningococcal bacteria were found in your blood or CSF sample. Most likely, your symptoms are not caused by meningococcal disease.

If your provider thinks you have meningococcal disease, you will get treatment with antibiotics. Ideally treatment will begin less than 24 hours after your diagnosis is confirmed.

If you have questions about your results, talk to your provider.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about a meningococcal disease test?

There are three types of meningococcal vaccines available in the U.S. While meningococcal disease is uncommon, it can cause serious illness and death in people of all ages. Meningococcal vaccines help protect against meningococcal disease.

The CDC recommends the meningococcal vaccine for all preteens, teens, and other children and adults at increased risk.

Ask your provider if they recommend that you or your child get a vaccine.