What is meningitis?
Meningitis is inflammation of the lining around the brain and spinal cord. It is usually caused by an infection.
The infection occurs most often in children, teens, and young adults. Also at risk are older adults and people who have long-term health problems, such as a weakened immune system.
There are two main kinds of meningitis:
- Viral meningitis is fairly common. It usually doesn't cause serious illness. In severe cases, it can cause prolonged fever and seizures.
- Bacterial meningitis isn't as common, but it's very serious. It needs to be treated right away to prevent brain damage and death.
What causes meningitis?
Viral meningitis is caused by viruses. Bacterial meningitis is caused by bacteria.
Meningitis can also be caused by other organisms and some medicines, but this is rare.
Most forms of meningitis are contagious. The germs that cause it can be passed from one person to another through coughing and sneezing and through close contact.
What are the symptoms?
The most common symptoms among teens and young adults are:
- A stiff and painful neck, especially when you try to touch your chin to your chest.
- Trouble staying awake.
Children, older adults, and people with other medical problems may have different symptoms:
- Babies may be cranky and refuse to eat. They may have a rash. They may cry when held.
- Young children may act like they have the flu. They may cough or have trouble breathing.
- Older adults and people with other medical problems may have only a slight headache and fever.
It is very important to see a doctor right away if you or your child has these symptoms. Only a doctor can tell whether they are caused by viral or bacterial meningitis. And bacterial meningitis can be deadly if not treated right away.
How is meningitis diagnosed?
Your doctor will ask questions about your health, do an exam, and use one or more tests.
Lumbar puncture is the most important lab test for meningitis. It is also called a spinal tap. A sample of fluid is removed from around the spine and tested to see if it contains organisms that cause the illness.
Your doctor may also order other tests, such as blood tests, a CT scan, or an MRI.
How is it treated?
Bacterial meningitis is treated with antibiotics in a hospital. You may also get dexamethasone, a type of steroid medicine. And you will be watched carefully to prevent serious problems such as hearing loss, seizures, and brain damage.
But viral meningitis is more common, and most people with this form of the illness get better in about 2 weeks. With mild cases, you may only need home treatment. Home treatment includes taking medicine for fever and pain and drinking enough fluids to stay hydrated.
Can meningitis be prevented?
The best way to protect your child from meningitis is to make sure he or she gets all the standard immunizations for children. These include shots for measles, chickenpox, Haemophilus influenzae type B (Hib) disease, and pneumococcal infection.
Talk to your doctor about whether you or your child also needs the meningococcal vaccine, which is a shot to prevent bacterial meningitis. Two doses are recommended for all adolescents. And at least one dose is recommended for anyone 6 weeks of age and older who has immune system problems or a damaged or missing spleen. The vaccine is also needed for travel to countries known to have meningitis outbreaks, such as the countries in Africa south of the Sahara Desert.
Most meningitis is caused by bacteria and viruses that often live in our bodies. Usually these germs stay in the intestines or in the nose and throat, where they may or may not make us sick. But if they spread to the tissues (meninges) that surround the brain and spinal cord, they cause inflammation. This inflammation is called meningitis.
The germs that can lead to meningitis are contagious, which means they can be passed from one person to another.
Viral meningitis is the most common and the least dangerous. It's caused by viruses, most often enteroviruses that live in the intestines. These viruses can be spread through food, water, or contaminated objects. Meningitis caused by enteroviruses occurs most often in babies and young children.
Bacterial meningitis is caused by bacteria. It is a very serious illness. These germs are usually passed from one person to another through infected saliva or mucus. Most people who get bacterial meningitis get it from one of two types of bacteria:footnote 1
- Streptococcus pneumoniae. This is a common type of bacteria that causes a number of illnesses besides meningitis, such as ear and sinus infections and pneumonia.
- Neisseria meningitidis . This is bacteria you can have in your throat without getting sick. But you can pass it to others, who may then get seriously ill with meningitis.
In the United States, bacterial meningitis mainly affects adults.footnote 2
Other types of bacteria that sometimes cause meningitis are:
- Group B streptococci. This type of meningitis occurs most often in newborns, who can become infected during or after birth.
- Listeria monocytogenes. This type of meningitis occurs most often in newborns and in older adults.
- Haemophilus influenzae type b. This type of meningitis occurs in both children and adults. It usually happens after an upper respiratory infection, such as a sinus infection.
The Centers for Disease Control and Prevention (CDC) recommends screening for group B streptococci in all pregnant women at 35 to 37 weeks. Women who have the bacteria are given antibiotics during labor in order to prevent infection in their newborns.footnote 3
In rare cases, other kinds of bacteria cause meningitis, usually in people with long-term medical conditions. Meningitis also can be caused by other organisms, such as a fungus, and by conditions such as cancer or lupus. Meningitis also can be a complication of an injury (particularly to the skull or face), or brain surgery.
How meningitis is spread
Germs that cause meningitis can be spread:
- During birth. A mother can pass germs that cause meningitis to her baby even if the mother doesn't have symptoms. Delivering a baby by cesarean section rather than through the birth canal doesn't always protect the baby from getting the infection. Both bacteria and viruses can be transmitted this way.
- Through stool. Stool could have enteroviruses or certain types of bacteria in it. Washing hands on a regular basis can help prevent you and your children from getting infected this way. More children than adults get meningitis this way.
- Through coughing and sneezing. Infected people can pass certain bacteria that are normally found in saliva or mucus in their noses and throats.
- Through kissing, sexual contact, or contact with infected blood. Some viruses also can cause meningitis and can be passed from an infected person to another person through blood, sexual contact, or kissing.
- From eating certain foods. Eating food contaminated with Listeria monocytogenes bacteria can cause meningitis. Those at greater risk for this include pregnant women and people with weakened immune systems.
- From rodents and insects (rare). For example, leptospirosis is a disease caused by bacteria that is spread through water or plants contaminated by the urine of infected mice, hamsters, and rats. And the St. Louis encephalitis and West Nile viruses are spread through mosquito bites.
Symptoms of bacterial meningitis usually appear suddenly.
Symptoms of viral meningitis may appear suddenly or develop gradually over a period of days. For example, the symptoms of viral meningitis after mumps may take several days or weeks to develop.
The most common symptoms of either form of meningitis include:
- Severe and persistent headache.
- Stiff and painful neck, especially when trying to touch the chin to the chest.
- Confusion and decreased level of consciousness.
Less common symptoms include:
- Sluggishness, muscle aches and weakness, and strange feelings (such as tingling) or weakness throughout the body.
- Eye sensitivity and eye pain from bright lights.
- Dark purple and blotchy skin rash.
- Dizzy spells.
Babies, young children, older adults, and people with other medical conditions may not have the usual symptoms of meningitis.
- In babies, the signs of meningitis may be a fever, irritability that is difficult to calm, decreased appetite, rash, vomiting, and a shrill cry. Babies also may have a stiff body and bulging soft spots on the head that aren't caused by crying. Babies with meningitis may cry when handled.
- Young children with meningitis may act like they have the flu (influenza), cough, or have trouble breathing.
- Older adults and people with other medical conditions may have only a slight headache and fever. They may not feel well and may have little energy.
Other conditions with symptoms similar to meningitis include viral hepatitis and flu.
The course of meningitis often depends on your age, general health, and the organism causing the infection. The illness can range from mild to severe.
Viral meningitis is more common in the late summer and early fall. It usually doesn't cause serious illness. A visit to the doctor followed by home treatment may be all you need.
You may get better within 2 weeks. But some people may feel lightheaded and tired for several months after the illness.
Bacterial meningitis occurs most often from late winter to early spring. It usually causes serious illness and can be life-threatening. The symptoms usually develop suddenly and last for 2 to 3 weeks. A person with bacterial meningitis is treated with antibiotics in a hospital.
Complications, short-term and long-term, are more common with bacterial than with viral meningitis. People with bacterial meningitis can die if not treated right away. People who are more likely to have these problems include:
- Newborns and young children.
- People with impaired immune systems.
- Older adults with long-term medical problems.
The risk of dying from bacterial meningitis is also higher for adults who:footnote 1
- Have seizures during the first 24 hours of illness.
- Are in shock or in a coma when admitted to the hospital.
- Can't breathe without help from a machine.
Most survivors recover completely.
What Increases Your Risk
A risk factor is anything that makes you more likely to get a certain disease. Risk factors for meningitis include:
- Genetics. Some people may inherit the tendency to get meningitis. If they come in contact with organisms that can cause the infection, they may be likely to get infected.
- Crowded living conditions. People in camps, day care centers, schools, and college dormitories are more likely to get meningitis.
- Being exposed to insects and rodents. People who live in or visit areas of the world where insects or rodents carry germs that cause meningitis risk getting the disease.
- Not getting childhood immunizations. People who didn't get shots for mumps, Hib disease, or pneumococcal infections before age 2 are more likely to get meningitis.
- Being an older adult who hasn't gotten a pneumococcal vaccine.
- Not having a working spleen, which is part of the body's immune system.
- Travel to areas where meningitis is common. For example, people traveling to the "meningitis belt" in sub-Saharan Africa should get a meningococcal shot.
Medical problems that can increase your risk include:
- Having a birth defect of the skull, a head injury, or brain surgery.
- Having kidney dialysis.
- Having other infections, such as upper respiratory infections, mumps, tuberculosis (TB), syphilis, Lyme disease, and illnesses caused by herpes viruses.
- Having a cochlear implant for severe hearing loss. Studies show that children with cochlear implants have an increased risk for bacterial meningitis.footnote 4, footnote 5
- Being born to a mother infected with an organism that causes meningitis. Viruses such as the enteroviruses and herpes viruses, as well as some bacteria, can be passed from an infected mother to a baby during birth.
- Having had meningitis in the past. Some people who have had meningitis are more likely than others to get it again. These include people with birth defects or injuries to the skull and face, impaired immune systems, or unexpected reactions to some medicines.
When should you call your doctor?
Call 911 or other emergency services right away if:
- You or your child has symptoms of severe meningitis, such as fever, seizures, and confusion.
- Your baby has signs of severe meningitis, such as trouble breathing or fever with a bulging soft spot on the head not caused by crying.
Call your doctor right away if:
- You or your child has symptoms of meningitis, such as severe and persistent headache, stiff neck, fever, rash, nausea, and vomiting.
- You or your child has viral meningitis and does not get better with home treatment after 3 days.
- You or your child is being treated for viral meningitis and develops signs of complications, such as a fever that lasts longer than 3 full days and does not go down during home treatment.
- Your baby has a fever that comes and goes, diarrhea, vomiting, a swollen abdomen, and a shrill cry.
Call a doctor soon if you think you may have been exposed to meningitis. You can be treated with antibiotics, which may keep you from getting the illness.
Watchful waiting is a period of time during which you and your doctor observe your symptoms or condition without using medical treatment.
Watchful waiting isn't appropriate if you think that you or your child has meningitis, because you can't tell what type of meningitis it may be. Call your doctor as soon as symptoms appear.
Who to see
The following health professionals can diagnose and treat meningitis:
- Family medicine physician or internist
- Emergency room doctor
- Pediatric nurse practitioner or family nurse practitioner
- Physician assistant
Specialists may be needed to treat meningitis, especially if complications develop:
Exams and Tests
Diagnosis of meningitis is based on a medical history, a physical exam, and tests.
Your doctor will almost always do a lumbar puncture. This is done by inserting a long, thin needle into the spinal canal. The doctor uses the needle to collect samples of spinal fluid to check for bacteria and viruses.
Other tests that may be done include:
- Complete blood count, to check for signs of infection.
- Blood culture, to check for infections.
- Urine test, to check for infection in the urinary tract.
- Chest X-ray, to check for lung infections.
- Biopsy of a skin rash.
- CT scan or MRI, to look for swelling of brain tissue or for complications such as brain damage.
Most people with viral meningitis usually start getting better within 3 days of feeling sick, and they recover within 2 weeks. With mild cases of viral meningitis, you may only need home treatment, including drinking extra fluids and taking medicine for pain and fever.
Bacterial or severe viral meningitis may require treatment in a hospital, including:
- Medicines such as antibiotics, corticosteroids, and medicines to reduce fever.
- Oxygen therapy, if you have trouble breathing. To learn more, see Other Treatment.
- Supportive care. In the hospital, doctors watch the person closely and provide care if needed. For example, you may need to drink extra liquids or get fluids in a vein (IV). To learn more, see Other Treatment.
Most healthy adults who have recovered from meningitis don't need follow-up care.
But adults who have other medical problems that make them more likely to have long-term complications or get meningitis again should see their doctors after recovery.
Babies and children always need follow-up care after recovery. They need to be checked for long-term complications such as hearing loss.
Childhood vaccinations are the best way to prevent meningitis. These shots prevent germs from causing some of the diseases that can lead to meningitis. They include shots for:
- Measles, mumps, and rubella (MMR).
- Hib disease.
- Pneumococcal disease (PPSV or PCV). Getting this shot usually protects people from the type of bacteria that is most likely to cause meningitis death.
- Meningococcal disease. This shot is also recommended for people whose risk is higher than normal, such as travelers to countries known to have outbreaks of meningitis, people without a spleen, and those who have HIV.
For more information about immunizations, see the topic Immunizations.
A link has been found between meningitis and cochlear implants for severe hearing loss. To help protect against meningitis, experts recommend that people with cochlear implants get a pneumococcal shot. Also, some people with implants have ear infections before they get meningitis, so it's important to treat ear infections right away with antibiotics.
Lowering your risk
Take steps to lower your risk of getting or spreading meningitis:
- Stay away from people who have it.
- Keep people with meningitis separate from other people in the home.
- Wash your hands often if you have meningitis or are taking care of someone who does. Wash your hands after using the toilet or helping a sick child use the toilet, after changing a sick baby's diaper, and after handling used bedsheets, towels, clothes, or personal items of a sick person.
- Avoid contact with wild animals. And take steps to prevent bites from bugs, such as mosquitoes and ticks, that might carry disease-causing bacteria or viruses.
- If you come in close contact with someone who has bacterial meningitis, call your doctor. Taking antibiotics may keep you from getting the illness. If your contact is only casual—for example, at school or at work—you don't need to take antibiotics.
Home treatment usually is all that is needed for most people who have viral meningitis. It includes:
- Resting. Rest promotes healing and provides relief from symptoms such as headache. Quiet activities, such as reading books, playing board games, watching videos, or listening to music, help pass the time.
- Reducing fever. Cool washcloths to the forehead, cool baths, and medicines such as acetaminophen (Tylenol) or ibuprofen (Advil) can be used to reduce fever, if needed. Be safe with medicines. Read and follow all instructions on the label.
- Relieving headaches and muscle aches. Minor pain usually can be relieved with medicines such as acetaminophen (Tylenol) or ibuprofen (Advil).
- Preventing dehydration . Drink liquids such as water, juices, teas, and rehydration drinks to keep from getting dehydrated. Children may enjoy frozen juice bars or snow cones. If a person vomits, he or she needs to avoid solid food and take frequent small sips of water or other liquids.
- Watching for signs of complications during illness. The most common complications include fever lasting for longer than expected and seizures. Some people with complications during illness may need to be treated in a hospital.
When you or your child is recovering at home, watch for signs of long-term complications of meningitis, such as hearing loss.
The decision about what medicine to use depends on the organism causing the infection, the extent of the infection, and the person's age and general health.
Medicines used for treating meningitis include:
- Antibiotics to treat bacterial infection. Often two antibiotics are given together. Antibiotics aren't given for viral meningitis.
- Medicines to treat seizures.
- Medicines to treat pressure on the brain.
- Medicines to treat fever and muscle aches. The most common ones are nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (Tylenol).
People who are very sick may need to be treated in the intensive care unit of a hospital. They may need one or both of these additional treatments:
- Oxygen therapy, to help them breathe and to reduce the amount of work on the heart. A pulse oximeter often is used to measure the amount of oxygen in the blood. Also, if people are too sick to breathe on their own, they may need a machine called a ventilator.
- Suctioning, to remove mucus from the bronchial tubes. A small plastic tube is inserted into the mouth or nose. The tube is attached to a machine that gently sucks out mucus. Other treatments, such as breathing exercises and massage, also can be used to remove mucus.
- Roos KL, Tyler KL (2015). Meningitis, encephalitis, brain abscess, and empyema. In DL Kasper et al., eds., Harrison's Principles of Internal Medicine, 19th ed., vol. 2, pp. 883–906. New York: McGraw-Hill Education.
- Tunkel AR, et al. (2010). Acute meningitis. In GL Mandell et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed., pp. 1189–1229. Philadelphia: Churchill Livingstone Elsevier.
- Verani JR, et al. (2010). Prevention of perinatal group B streptococcal disease: Revised guidelines from CDC, 2010. MMWR, 59(RR-10): 1–36. Also available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5910a1.htm?s_cid=rr5910a1_w.
- Reefhuis J, et al. (2003). Risk of bacterial meningitis in children with cochlear implants. New England Journal of Medicine, 349(5): 435–445.
- Biernath KR, et al. (2006). Bacterial meningitis among children with cochlear implants beyond 24 months after implementation. Pediatrics, 117(2): 284–289.
Current as of: June 9, 2019
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
W. David Colby IV MSc, MD, FRCPC - Infectious Disease
Current as of: June 9, 2019