What is meningitis? What causes meningitis?
There are many potential causes of meningitis.
Meningitis is an infection of the meninges or coverings of the brain. This serious illness can progress very quickly and have lifelong consequences. So, it is important to get medical attention as soon as possible. The most frequent cause of meningitis is a viral or bacterial infection. Rarely, a fungus can cause it. Knowing the cause of meningitis is important because viral meningitis is usually less severe and generally people get better without any treatment. However, bacterial meningitis can be profoundly serious and needs to be treated with the right antibiotics. Bacterial meningitis can have some serious side effects. Symptoms can happen very fast, even within a few hours, or they can gradually develop in a day or two.
- Meningitis is a deadly disease that can develop very quickly and kill in hours. It can happen to anyone of any age.
- This disease is most common in babies, young children, and teenagers. However, cases in young adults are being increasingly reported.
Meningococcal disease (the combination of meningitis and septicemia) causes death in about one in 10 cases. Even after bacterial meningitis is cured, some children may develop complications, such as hearing loss. With early diagnosis and proper treatment, a child with meningitis has a reasonable chance of a good recovery, though some forms of bacterial meningitis develop rapidly and have a high risk of complications.
Is Meningitis Contagious?
The contagiousness is related to the specific agent that causes the disease. The following is a summary of five types of meningitis and how they may or may not be contagious.
- Viral meningitis: Meningitis caused by many viruses is usually contagious. However, certain viruses that are transmitted by mosquitoes are usually not spread person to person, so they are not contagious.
- Bacterial meningitis: Bacterial meningitis is usually contagious; some bacteria more highly contagious (such as Neisseria meningitidis in young adults and Streptococcus pneumonia in all ages) than others.
- Fungal meningitis: Fungal meningitis (for example, Cryptococcus meningitis) is not considered to be contagious.
- Parasitic meningitis: Parasitic meningitis, which is rare (for example, Naegleria fowleri), is not considered to be contagious from person to person.
- Noninfectious meningitis: Noninfectious meningitis is not a result of infection but is from an underlying condition or disease and not considered contagious. Causes of noninfectious meningitis include cancers in and around the brain or spinal cord, drugs, head injury, and autoimmune disease (such as lupus or Behçet's disease).
What are meningitis symptoms and signs?
Meningitis is a swelling of the tissues that cover the brain and spinal cord. The swelling sometimes affects the brain itself. Meningitis can be hard to recognize in the early stages. Symptoms can be similar to those of the common flu and can develop quickly over hours. The most common symptoms and signs among teens and young adults are
- a stiff and painful neck, especially when trying to touch the chin to the chest;
- high fever;
- trouble staying awake; and
Children, older adults, and people with other medical problems may have different signs and symptoms.
- Babies may be cranky and refuse to eat.
- They may have a rash.
- They may cry when held or appear listless.
- 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 important to see a doctor right away if these symptoms appear. Only a doctor can order the specific tests that indicate whether the symptoms are caused by viral or bacterial meningitis. When meningitis is suspected, there are multiple tests a doctor can conduct to confirm a diagnosis.
- Blood cultures: Blood tests can indicate an infection. Blood samples are studied to see if microorganisms, such as bacteria, are growing.
- Imaging: Computed tomography (CT) or magnetic resonance imaging (MRI) scans of the head can show swelling or inflammation associated with meningitis. CT scans of the chest or sinuses can also show infections in other associated areas.
- Spinal tap: To get a definitive diagnosis of meningitis, a spinal tap or lumbar puncture is needed. This procedure collects cerebrospinal fluid that can show glucose and protein levels, as well as a white blood cell count.
Bacterial Infections 101: Types, Symptoms, and Treatments
What are meningitis treatments?
Treatment of meningitis depends on the cause.
- It is treated immediately with intravenous antibiotics.
- This helps ensure the recovery of the patient and reduces the risk of complications, such as brain swelling and seizures.
- It is usually mild and often clears on its own.
- Treatment may include supportive care, such as resting, keeping warm and comfortable, and drinking plenty of fluids.
- Viral meningitis cannot be treated with antibiotics.
- This may be treated with corticosteroids.
- In some cases, no treatment may be required because the condition can get better on its own.
- Cancer-related meningitis requires therapy to manage cancer.
- Immunization against the meningococcus bacterium may be recommended when an outbreak (defined as three cases of the same type within three months) of meningococcal disease has occurred in a community.
- It is important to note that the meningococcal vaccine should not be used in place of treatment for those exposed to an infected person. The protection from immunization is quite slowly developed in this situation.
- Immunization against the bacterium Neisseria meningitides may be recommended for people older than 2 years of age if they are members of a population that is experiencing an outbreak of meningococcal disease. For example, students at a university where an outbreak has occurred.
- Untreated bacterial meningitis has an extremely high death rate. Even with appropriate treatment, the death rate from bacterial meningitis is about 15 to 20 percent with a higher death rate associated with increasing age. The type of bacteria makes a difference. Pneumococcal and Listeria meningitis is associated with higher death rates than meningococcal meningitis. Patients who survive may be left with long-term disabilities, such as deafness, blindness, seizures, paralysis, impaired mental status, and loss of limbs or weakness in the limbs. Viral meningitis, however, is associated with an exceptionally good prognosis and generally leads to a full recovery. Many strains of bacteria that cause bacterial meningitis are now preventable by vaccination, such as Haemophilus influenzae type b (Hib), meningococcus serogroups A, B, C, W135, and Y and pneumococcus.
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Medically Reviewed on 6/23/2021
Escoto, Marcella A. "Meningitis." KidsHealth.og. January 2019. <https://kidshealth.org/en/parents/meningitis.html>.
"Frequently Asked Meningitis Questions." MeningitisNow.org. <https://www.meningitisnow.org/meningitis-explained/what-is-meningitis/frequently-asked-questions/>.
United Kingdom. "Meningitis." National Health Service. Mar. 8, 2019. <https://www.nhs.uk/conditions/meningitis/>.