Bacterial meningitis is an inflammation of the meninges, the protective layers that cover the brain and spinal cord. It occurs when bacteria enter the nervous system, leading to symptoms such as fever, headache, and neck stiffness.

Most people recover from bacterial meningitis when treatment is started quickly and followed exactly as prescribed by a doctor.

However, if left untreated, the infection can cause serious complications, including brain damage, hearing loss, and learning difficulties.

male provider talking to female patient with eyes closed and hands on sides of her head

Bacterial meningitis symptoms

The main symptoms of bacterial meningitis include:

High fever;
Severe headache;
Neck pain or stiffness;
Vomiting and loss of appetite;
Extreme fatigue or muscle weakness;
Paralysis, which may affect only one side of the body;
Confusion or seizures.

Other possible symptoms include purple or red spots on the skin, changes in vision, and sensitivity to light.

In babies, the classic symptoms may be absent or difficult to identify. Common signs include irritability, persistent crying, seizures, and a bulging or firm soft spot (fontanelle).

Confirming a diagnosis

A diagnosis of bacterial meningitis is made based on a person's symptoms and the results of a cerebrospinal fluid (CSF) analysis, which may be ordered by a doctor to check for the presence of bacteria.

If the test is positive, a sensitivity test may also be done to determine which antibiotic is most effective for treating the infection.

Possible causes

The main bacteria responsible for bacterial meningitis include:

Streptococcus pneumoniae;
Neisseria meningitidis;
Group B Streptococcus;
Listeria monocytogenes;
Haemophilus influenzae.

Additionally, Escherichia coli (E. coli) can also cause bacterial meningitis.

Risk factors

The main factors that increase the risk of developing bacterial meningitis include:

Babies and children under 3 years old, since their immune systems are still developing;
Older adults, who tend to have weaker immune systems and other underlying health conditions;
Chronic illnesses such as pneumonia, sinus infections, ear infections, and diabetes;
Surgical procedures or anatomical defects, such as head trauma, absence of the spleen, or cerebrospinal fluid leaks
Weakened immune systems due to HIV infection, organ transplant, or severe malnutrition

Bacterial meningitis can also occur in people who use medications such as eculizumab or ravulizumab, those exposed to bacteria at work, or travelers to regions where the disease is common.

Although it can affect people of all ages, newborns, babies, and young children are at the highest risk.

Transmission and spread

Bacterial meningitis spreads through direct person-to-person contact via droplets from the nose or mouth of infected individuals.

Because of this, people with meningitis should wear a face mask and avoid coughing, sneezing, or speaking close to others.

Newborns can become infected with group B Streptococcus during vaginal delivery, as the bacteria can be present in the mother’s birth canal without causing symptoms. See group b strep test and pregnancy.

Another possible route of infection is through eating contaminated food containing Listeria monocytogenes, such as raw vegetables, unpasteurized dairy, or processed meats like hot dogs and cold cuts.

Bacterial meningitis can often be prevented through vaccination against Haemophilus influenzae type b and Streptococcus pneumoniae, with doses starting at 2 months of age. Meningococcal vaccines are reserved for children at higher risk or given later in adolescence.

Treatment options

Treatment for bacterial meningitis is carried out in a hospital setting with intravenous (IV) antibiotics, chosen based on the specific bacteria and its resistance profile.

The following table outlines typical guidelines for antibiotic use based on the bacteria responsible for the meningitis:

Bacteria responsible for meningitis	Antibiotic used
*Neisseria meningitidis*	Ceftriaxone or cefotaxime; penicillin G or ampicillin may be used if the strain is confirmed susceptible
*Streptococcus pneumoniae*	Ceftriaxone or cefotaxime plus vancomycin until susceptibility results are available; penicillin G or ampicillin may be used if the strain is fully susceptible
*Haemophilus influenzae*	Ceftriaxone or cefotaxime; ampicillin may be used if the strain is β-lactamase negative
*Listeria monocytogenes*	Ampicillin, sometimes combined with gentamicin for synergy; trimethoprim-sulfamethoxazole (TMP-SMX) may be used in patients allergic to penicillin
*Group B Streptococcus (Streptococcus agalactiae)*	Penicillin G or ampicillin; cefotaxime may be used as an alternative

Before the bacteria causing the infection is identified, empiric treatment is typically started as follows:

Newborns (<1 month): Ampicillin + cefotaxime (or gentamicin);
Children and adults (1 month–50 years): Ceftriaxone or cefotaxime + vancomycin;
Adults over 50 years or immunocompromised individuals: Ampicillin + ceftriaxone (or cefotaxime) + vancomycin.

Patients are usually kept in isolation for the first 24 hours after beginning antibiotic therapy and can be discharged after 14 to 28 days, once they are fully recovered.

Can bacterial meningitis be cured?

Bacterial meningitis can be cured when treatment is followed exactly as prescribed by a doctor. Antibiotics should not be stopped early, even if symptoms improve, but only when the doctor confirms that the infection has been completely cleared.

Following medical instructions ensures full elimination of the bacteria causing meningitis.

Possible complications

Complications of bacterial meningitis may occur when treatment is delayed or not properly followed, especially in older adults or children.

The main complications include brain damage, hearing loss, motor paralysis, epilepsy, and learning difficulties

Bacterial Meningitis: Symptoms, Causes & Treatment