Meningitis is an inflammation of the meninges, the membranes that cover the brain and spinal cord. Most cases are caused by bacteria or viruses, but some can be due to certain medicines or illnesses.
Bacterial meningitis is rare, but is usually serious and can be life-threatening if not treated right away. Viral meningitis (also called aseptic meningitis) is more common and far less serious. It often goes undiagnosed because its symptoms can be similar to those of the common flu.
People of any age can get meningitis, but because it can spread easily among those living in close quarters, teens, college students, and boarding-school students are at higher risk for infection.
If dealt with quickly, meningitis can be treated successfully. So it's important to get routine vaccinations, know the signs of meningitis, and get medical care right away if you think that your child has the illness.
Causes of Meningitis
Many of the bacteria and viruses that cause meningitis are fairly common and associated with other routine illnesses. Thos that infect the skin, urinary system, or gastrointestinal and respiratory tract can spread via the bloodstream to the meninges through cerebrospinal fluid, the fluid that circulates in and around the spinal cord.
In some cases of bacterial meningitis, the bacteria spread to the meninges from a severe head trauma or a severe local infection, such as a serious ear infection (otitis media) or nasal sinus infection (sinusitis).
Bacterial and Viral Types
Many different types of bacteria can cause bacterial meningitis. In newborns, the most common causes are Group B streptococcus, Escherichia coli, and less commonly, Listeria monocytogenes. In older kids, Streptococcus pneumoniae (pneumococcus) and Neisseria meningitidis (meningococcus) are more often the causes.
Another bacteria, Haemophilus influenza type b (Hib), also can cause the illness but because of widespread childhood immunization, these cases are rarer.
Many different viruses also can lead to viral meningitis, including enteroviruses (such as coxsackievirus and poliovirus) and the herpesvirus.
Symptoms of Meningitis
Meningitis symptoms vary, depending both on the person's age and the cause of the infection. The first symptoms can come on quickly or start several days after someone has had a cold, diarrhea and vomiting, or other signs of an infection.
Infants with meningitis may not have the typical symptoms. Instead, they might be very irritable, tired, and have a fever. They may be difficult to comfort, even when picked up and rocked.
Other symptoms of meningitis in infants can include:
jaundice (a yellowish tint to the skin)
stiffness of the body and neck
a lower-than-normal temperature
a weak suck
a high-pitched cry
bulging fontanelles (the soft spot at the top/front of the baby's skull)
Viral meningitis tends to cause flu-like symptoms, such as fever and headache, and may be so mild that the illness goes undiagnosed. Most cases of viral meningitis end within 7 to 10 days, without any complications or need for treatment.
Bacterial meningitis can be very serious. So if you see symptoms or think that your child could have meningitis, it's important to see the doctor right away.
If meningitis is suspected, the doctor will order tests, probably including a lumbar puncture (spinal tap) to collect a sample of spinal fluid. This test will show any signs of inflammation and whether a virus or bacteria is causing the infection.
Someone with viral meningitis might need to be treated in the hospital, although some kids can recover at home if they are not too ill. Treatment to ease symptoms includes rest, fluids, and over-the-counter pain medicine.
If bacterial meningitis is diagnosed — or even suspected — doctors will start intravenous (IV) antibiotics as soon as possible. Fluids may be given to replace those lost to fever, sweating, vomiting, and poor appetite.
Complications of bacterial meningitis might require further treatment (for example, anticonvulsants might be given for seizures). Someone with shock or low blood pressure might get more IV fluids and medicines to increase blood pressure. Some kids may need extra oxygen or mechanical ventilation if they have trouble breathing.
Bacterial meningitis complications can be severe and include neurological problems, such as hearing loss, visual impairment, seizures, and learning disabilities. Because impaired hearing is a common complication, those who've had bacterial meningitis should have a hearing test after they recover.
The heart, kidneys, and adrenal glands also might be affected, depending on the cause of the infection. Although some kids develop long-lasting neurological problems, most who receive prompt diagnosis and treatment recover fully.
Most meningitis cases — both viral and bacterial — are due to contagious infections that spread via tiny drops of fluid from the throat and nose of someone who is infected. The drops get into the air when the person coughs, laughs, talks, or sneezes. Others become infected when they breathe in the drops or touch a contaminated surface and then touch their own noses or mouths.
Sharing food, drinking glasses, eating utensils, tissues, or towels also can spread infection. Some germs can spread through a person's stool (poop), and someone who comes in contact with the stool — such as kids in daycare — may develop the infection.
Infections spread easily between people who are in close contact, such as those who live together or people who are exposed by kissing or sharing eating utensils.
Routine immunization can go a long way toward preventing meningitis. The vaccines against Hib, measles, mumps, polio, meningococcus, and pneumococcus can protect against meningitis caused by these germs.
Doctors now recommend that kids get vaccinated for meningococcal disease with a vaccine called meningococcal conjugate vaccine when they're 11 or 12 years old, with a booster shot at age 16. Kids older than 11 who haven't vaccinated also should be immunized, particularly if they're going to college, boarding school, camp, or other settings where they'll live in close quarters with others.
This vaccine also might be recommended for kids 2 months to 18 years old who have certain high-risk medical problems, and for people traveling to countries where meningitis is more common.
A newer type of meningococcal vaccine called MenB (which protects against a type of meningococcal bacterium not covered by the older vaccine) may be given to teens and young adults at the discretion of their doctor. It's recommended that kids 10 and older who are at higher risk for meningococcal disease (those with immune system disorders, or who live in or travel to countries where the disease is common) get the MenB vaccine in addition to the meningococcal conjugate vaccine.
Many of the bacteria and viruses responsible for meningitis are fairly common, so good hygiene is an important way to prevent infection. Kids should wash their hands well and often, particularly before eating and after using the bathroom. Avoiding close contact with someone who is obviously ill and not sharing food, drinks, or eating utensils also can help stop the spread of germs.
In some cases, doctors may give antibiotics to anyone who has been in close contact with a person who has bacterial meningitis to help prevent infection.
When to Call the Doctor
Get medical care right away if you think that your child has meningitis or you see symptoms such as vomiting, headache, lethargy or confusion, neck stiffness, rash, and fever. A baby who has a fever, is irritable, and isn't feeding well also should be seen right away by a doctor.
If your child has been near someone who has meningitis (for example, in a childcare center or a college dorm), call your doctor to ask whether preventive medicine is recommended.