What Is Meningitis?
Meningitis is an inflammation of the membranes that cover the brain and spinal cord, and is sometimes referred to as “spinal meningitis”.
What are the meninges?
As a protective membrane, the three-layered meninges (made up of the pia mater, dura mater, and arachnoid mater) prevent infectious materials from coming into contact with the central nervous system (brain and spinal cord), protect the all-important brain and spinal cord from injury, and provide a space where cerebrospinal fluid (CSF) circulates. The brain essentially “floats” in a sea of cerebrospinal spinal fluid between two layers of the meninges, and this provides shock absorption for this most essential of organs.
Bacterial, Viral & Fungal Meningitis
Meningitis is generally caused by a bacteria, virus or (rarely) a fungus. Determining the cause of the illness is crucial to its proper treatment. Viral meningitis is generally less severe than a bacterial infection, and affected individuals can often recover without specific treatment other than supportive measures.
In terms of bacterial meningitis, an untreated infection can lead to brain damage, hearing loss, learning disabilities, and death. Prior to 1990, Haemophilus influenza Type B (HiB) was the leading cause of bacterial meningitis, but the introduction of the HiB vaccine has significantly decreased the frequency of this type of bacterial meningitis. Streptococcus pneumoniae and Neisseria meningitidis are now the most commonly detected bacteria causing worldwide cases of bacterial meningitis.
Viral meningitis (also known as “aseptic meningitis”) is very rarely fatal in persons with normal immune function, but can be dangerous for the young, the elderly, and those with compromised immunity.
Fungal meningitis is rare and usually the result of spread of a fungus through blood to the spinal cord. It is not contagious, and although anyone can get fungal meningitis, people with weak immune systems, like those with AIDS or cancer, are at higher risk. The most common cause of fungal meningitis for people with weak immune systems is Cryptococcus. This disease is one of the most common causes of adult meningitis in Africa.
Signs and Symptoms of Meningitis
The cardinal symptoms of meningitis are headache, stiff neck, and high fever. Symptoms can also include nausea, vomiting, confusion, lethargy, sleepiness, seizures, and photophobia (pain and discomfort when looking at bright lights). Infants with meningitis may not demonstrate symptoms of stiff neck, fever and headache, but may show signs of lethargy, difficulty waking, irritability, vomiting and loss of appetite.
Meningitis is diagnosed by obtaining a sample of cerebrospinal fluid via a procedure known as a “spinal tap”. During a spinal tap, a needle is inserted into the spine and CSF is extracted from the space between two layers of the meninges. The sample of is then sent to a laboratory where the cause is then identified.
When bacterial meningitis is diagnosed, antibiotics are prescribed for the specific organism identified in the laboratory. According to the Centers for Disease Control, proper treatment with appropriate antibiotics reduces mortality from bacterial meningitis to less than 15%.
If viral meningitis is diagnosed, doctors usually recommend bed rest, fluids, and medicine to relieve headache and fever.
Is Meningitis Contagious?
Some forms of bacterial meningitis can be spread via respiratory secretions through kissing, sneezing and coughing. However, meningitis cannot be spread by breathing the air in a room where an infected person has been without direct contact with respiratory droplets.
If an individual has been infected with the bacteria Neisseria meningitidis (also known as meningococcal meningitis), close and sustained contact in venues such as daycare centers can indeed lead to infection for more casual contacts. In such cases, prophylactic vaccination for household members and close contacts may be recommended by a medical provider.
Some forms of viral meningitis can be transmitted from one person to another via contact with the infected person’s stool (as in a daycare center), or via respiratory secretions.
Fungal meningitis is not contagious, and is generally contracted after taking medications that weaken the immune system and subsequently inhaling fungal spores in the air, such as those from infected soil.
Who Is At Risk?
College students living in dormitories are highly susceptible to meningitis, and outbreaks frequently occur in these venues. Young children, the elderly, and those with immune disorders are also particularly susceptible, although even healthy individuals can contract meningitis under the right conditions.
Can Meningitis Be Prevented?
A vaccine against meningococcal meningitis is now available and widely recommended for those beginning college. In fact, some colleges and universities now require vaccination.
The pneumococcal polysaccharide vaccine (PPSV) is routinely given to individuals 65 years and older, and this vaccine can give considerable protection against pneumococcal meningitis. Infants routinely receive the pneumococcal conjugate vaccine (PCV13), and this also provides protection against various illnesses caused by the pneumococcal bacteria, including meningitis.
The spreading of meningitis can be prevented by good hand hygiene, the use of proper technique for covering the mouth and nose when sneezing and coughing, as well as the thorough cleaning of potentially contaminated surfaces with a bleach solution (1/4 cup per gallon of water). It is also recommended to avoid close contact with the respiratory or throat secretions of ill individuals, and this includes the sharing of cups, eating utensils, and lipstick.
Some diseases—like mumps, measles, chickenpox, and diseases spread by mosquitoes and other insects—can lead to meningitis infection, thus prevention of mosquito bites and vaccination against common vaccine-preventable illnesses can also reduce the risk of infection with meningitis. Epstein-Barr virus, influenza and other common viral illnesses can result in meningitis, thus proper self-care, annual influenza vaccines, and a strong immune system are excellent tools to prevent unnecessary illness and infection.
Meningitis: Be Aware
Meningitis is an illness that can affect a variety of individuals, including those who are chronically ill and those who are generally healthy. Widely available vaccines and good self-care can serve to protect against the overall risk of infection, and particular vaccines are available for the prevention of specific types of bacterial meningitis. Parents, teachers and those who work with young children should understand the general symptoms of meningitis infection, keeping in mind that swift medical attention and diagnosis are crucial for proper treatment and a healthy recovery.