More than 1.2 million cases of bacterial meningitis are estimated to occur worldwide each year. (1) It’s hard to get precise numbers for the rate of incidence, but according to a 2011 study, there were approximately 3,200 cases of bacterial meningitis and 500 deaths from the disease in the United States between 2003 and 2007. (2)

Stiff neckHeadacheFever

If your neck is so stiff that you can’t touch your chin to your chest, call a doctor immediately. Other symptoms include:

Sensitivity to light (photophobia) ConfusionSeizures Coma

Bacterial meningitis can also cause the following complications:

Brain damage Hearing lossLearning disabilitiesDeath

Pneumococcal meningitisMeningococcal meningitisListeria monocytogenes meningitisNeonatal meningitisHemophilus (Hib) meningitis

Meningococcal meningitis, caused by the bacteria Neisseria meningitidis, is the most common type of bacterial meningitis among teenagers and children under age 5. (1) According to the National Meningitis Association, the B strain accounts for one-third of meningococcal disease in the United States and is the most common cause of bacterial meningitis in teenagers. (5)

Group B streptococcus (GBS)E. coli

Group B strep infection is the main cause of neonatal meningitis; infants contract it from their mothers during birth. Because of this, the CDC recommends that if you are pregnant, you should talk with your care team about getting a GBS test when you are 35 to 37 weeks pregnant. (7) Doctors will administer antibiotics during labor to women who test positive in order to prevent infection in newborns. Premature infants are at particular risk for bacterial meningitis caused by E. coli. (8) This bacteria, which is becoming resistant to antibiotics, is hard to assess and hard to treat. Pregnant women, infants, and people with weak immune systems, such as the elderly, are also at higher risk of developing meningitis from Listeria monocytogenes. Pregnant women can pass the bacteria to their newborns, potentially resulting in neonatal meningitis. There are a number of ways for pregnant women to reduce their risk of getting a listeria infection and passing it on to their newborns, including by:

Fully cooking meat and poultryEliminating certain foods from the diet while pregnant, including unpasteurized (raw) milk and soft cheeses, such as Brie, Camembert, queso fresco, and fetaEither avoiding lunch meats and hot dogs while pregnant or heating them to at least 165 degrees F (74 degrees C) before eatingKeeping the kitchen environment clean before, during, and after cookingThoroughly rinsing raw produceScrubbing firm produce

This agent used to be responsible for up to 48 percent of all bacterial meningitis cases, according to a 2010 review. (9) The Hib vaccine has virtually eliminated Hib meningitis in infants and children in the United States, though Hib is still a major cause of pediatric meningitis around the world.

SalmonellaStaphylococcus aureusPseudomonas aeruginosa 

About 1 in 10 people carry meningococcal bacteria in their nose or throat but don’t get sick from it; these carriers can still transmit the bacteria without knowing it. (10) Risk factors for bacterial meningitis include:

Age — infants, teens, and young adults are at particular risk Spending time in crowded quarters, such as in college or boarding school dormitories, military barracks, or daycare settingsDiseases, medication, or surgical procedures that weaken the immune systemWorking with meningitis-causing bacteriaTraveling to the so-called “meningitis belt” in sub-Saharan Africa during the dry season, which is December through June (11,12)

AntibioticsDexamethasone Fluid replacement

Antibiotics can reduce the risk of death to below 15 percent. (13) Preventive antibiotics can also help protect you from becoming infected with N. meningitidis or Hib if you have close contact with someone with those forms of meningitis. Dexamethasone is a steroid that helps control swelling and pressure in the skull.

PneumococcalMeningococcalHib

There are two types of pneumococcal meningitis vaccines available in the United States. They are: (14)

Prevnar 13 Pneumovax 23 

There are four types of meningococcal vaccines available. Two protect against the B strain of meningococcus, which is most likely to cause an outbreak. They are:

TrumenbaBexsero

Two vaccines protect against the A, C, W-135, and Y strains. They are:

MenactraMenveo

The CDC recommends that people traveling to or residing in the meningitis belt in sub-Saharan Africa receive a meningococcal meningitis vaccine that protects against those four strains. (14) This map from the CDC denotes the countries that are at high risk. There are several types of vaccines for Hib as well; they are recommended for children under age 5. (15) They include:

ActHIBHiberixPedvaxHIBPentacel (this also prevents tetanus, diphtheria, whooping cough, and polio)

Additional reporting by Carlene Bauer.