What is Meningitis?
Meningitis is an inflammation of the meninges which are the three membranes that cover or surround and protect the brain and spinal cord. Meningitis can occur when fluid surrounding the meninges becomes infected by bacteria.
The most common causes of meningitis are viral and bacterial infections. Other causes may include:
- drug allergies
- chemical irritation
- Some viral and bacterial meningitis are contagious. They can be transmitted by coughing, sneezing, or close contact.
Symptoms of Meningitis
The symptoms of viral and bacterial meningitis can be similar in the beginning. However, bacterial meningitis symptoms are usually more severe. The symptoms also vary depending on your age.
Fungal meningitis symptoms
Symptoms of fungal meningitis resemble the other types of this infection. These may include:
- confusion or disorientation
- sensitivity to light
Each type of meningitis has some distinguishing symptoms.
Viral meningitis symptoms
Viral meningitis in infants may cause:
- decreased appetite
In adults, viral meningitis may cause:
- sensitivity to bright light
- nausea and vomiting
- decreased appetite
- stiff neck
Bacterial meningitis symptoms
Bacterial meningitis symptoms develop suddenly. They may include:
- altered mental status
- sensitivity to light
- stiff neck
- purple areas of skin that resemble bruises
Seek immediate medical attention if you experience these symptoms. Bacterial and viral meningitis can be deadly. There’s no way to know if you have bacterial or viral meningitis just by judging how you feel. Your doctor will need to perform tests to determine which type you have.
One of the late signs that one bacterial cause of meningitis, Neisseria meningitidis, are in your bloodstream is a faint rash on your skin. The bacteria from a meningococcal meningitis infection reproduce in your blood and target cells around the capillaries. Damage to these cells leads to capillary damage and mild blood leaks. This shows up as a faint pink, red, or purple rash. The spots may resemble tiny pinpricks and are easily mistaken as a bruise.
As the infection worsens and spreads, the rash will become more obvious. The spots will grow darker and larger.
People with dark skin may have a hard time seeing meningitis rash. Lighter areas of skin, such as the palms of hands and the inside of the mouth may show signs of a rash more easily.
Not every rash looks the same.
Diagnosis of Meningitis
Diagnosing meningitis starts with a health history and physical exam. Age, dorm residence, and day care center attendance can be important clues. During the physical exam, your doctor will look for:
- neck stiffness
- a fever
- an increased heart rate
- reduced consciousness
Your doctor will also order a lumbar puncture. This test is also called a spinal tap. It allows your doctor to look for increased pressure in the central nervous system. It can also find inflammation or bacteria in the spinal fluid. This test can also determine the best antibiotic for treatment.
Other tests may also be ordered to diagnose meningitis. Common tests include the following:
- Blood cultures identify bacteria in the blood. Bacteria can travel from the blood to the brain. N. meningitidis and S. pneumonia, among others, can cause both sepsis and meningitis.
- A complete blood count with differential is a general index of health. It checks the number of red and white blood cells in your blood. White blood cells fight infection. The count is usually elevated in meningitis.
- Chest X-rays can reveal the presence of pneumonia, tuberculosis, or fungal infections. Meningitis can occur after pneumonia.
- A CT scan of the head may show problems like a brain abscess or sinusitis. Bacteria can spread from the sinuses to the meninges.
- Your doctor may also conduct a glass test. For this test, your doctor will roll a glass over the meningitis rash. If the rash doesn’t fade under the pressure, it’s likely meningitis rash. If it does fade, the unusual spots on the skin may be the result of another condition.
Types of Meningitis
Viral and bacterial infections are the most common causes of meningitis. There are several other forms of meningitis. Examples include cryptococcal, which is caused by a fungal infection, and carcinomatous, which is cancer-related. These types are less common.
Viral meningitis is the most common type of meningitis. Viruses in the Enterovirus category cause 85 percent of cases. These are more common during the summer and fall, and they include:
- coxsackievirus A
- coxsackievirus B
Viruses in the Enterovirus category cause about 10 to 15 million infections per year, but only a small percentage of people who get infected will develop meningitis.
Other viruses can cause meningitis. These include:
- West Nile virus
- influenza mumps
- Coltivirus, which causes Colorado tick fever
Viral meningitis typically goes away without treatment. However, some causes do need to be treated.
Bacterial meningitis is contagious and caused by infection from certain bacteria. It’s fatal if left untreated. Between 5 to 40 percent of children and 20 to 50 percent of adults with this condition die. This is true even with proper treatment.
The most common types of bacteria that cause bacterial meningitis are:
- Streptococcus pneumoniae, which is typically found in the respiratory tract, sinuses, and nasal cavity and can cause what’s called “pneumococcal meningitis”
- Neisseria meningitidis, which is spread through saliva and other respiratory fluids and causes what’s called “meningococcal meningitis”
- Haemophilus influenza, which can cause not only meningitis but infection of the blood, inflammation of the windpipe, cellulitis, and infectious arthritis
- Listeria monocytogenes, which are foodborne bacteria
Staphylococcus aureus, which is typically found on the skin and in the respiratory tract, and causes “staphylococcal meningitis”
- Fungal meningitis
Fungal meningitis is a rare type of meningitis. It’s caused by a fungus that infects your body and then spreads from your bloodstream to your brain or spinal cord.
People with a weakened immune system are more likely to develop fungal meningitis. This includes people with cancer or HIV.
The most common funguses related to fungal meningitis include:
- Cryptococcus, which is inhaled from dirt or soil that is contaminated with bird droppings
- Blastomyces, another type of fungus found in soil, particularly in the Midwestern United States
- Histoplasma, which is found in environments that are heavily contaminated with bat and bird droppings, especially in the Midwestern States near the Ohio and Mississippi Rivers
- Coccidioides, which is found in soil in specific areas of the U.S. Southwest and South and Central America
- Parasitic meningitis
This type of meningitis is less common than viral or bacterial meningitis, and it’s caused by parasites that are found in dirt, feces, and on some animals and food, like snails, raw fish, poultry, or produce.
One type of parasitic meningitis is rarer than others. It’s called eosinophilic meningitis (EM). Three main parasites are responsible for EM. These include:
- Angiostrongylus cantonensis
- Baylisascaris procyonis
- Gnathostoma spinigerum
Parasitic meningitis is not passed from person to person. Instead, these parasites infect an animal or hide out on food that a human then eats. If the parasite or parasite eggs are infectious when they’re ingested, an infection may occur.
One very rare type of parasitic meningitis, amebic meningitis, is a life-threatening type of infection. This type is caused when one of several types of ameba enters the body through the nose while you swim in contaminated lakes, rivers, or ponds. The parasite can destroy brain tissue and may eventually cause hallucinations, seizures, and other serious symptoms. The most commonly recognized species is Naegleria fowleri.
Non-infectious meningitis is not an infection. Instead, it is a type of meningitis that’s caused by other medical conditions or treatments. These include:
- brain surgery
- certain medications
- a head injury
Causes of Meningitis
Each type of meningitis has a slightly different cause, but each ultimately acts in the same way: A bacterium, fungus, virus, or parasite spreads through the bloodstream until it reaches the brain, or spinal cord. There, it sets up in the lining or fluids around these vital body parts and starts developing into a more advanced infection.
Non-infectious meningitis is the result of a physical injury or other condition; it doesn’t involve an infection.
Prevention of Meningitis
Maintaining a healthy lifestyle, especially if you’re at increased risk, is important. This includes:
- getting adequate amounts of rest
- not smoking
- avoiding contact with sick people
If you’ve been in close contact with one or more people who have a bacterial meningococcal infection, your doctor can give you preventive antibiotics. This will decrease your chances of developing the disease.
Vaccinations can also protect against certain types of meningitis. Vaccines that can prevent meningitis include the following:
- Haemophilus influenzae type B (Hib) vaccine
- pneumococcal conjugate vaccine
- meningococcal vaccine
Practicing good personal hygiene may also help you prevent meningitis. Some types of meningitis are spread through close contact with an infected person’s body fluid, such as saliva and nasal secretions. Avoid sharing drinks, utensils, and personal items that may carry saliva or other fluids. Take these steps to prevent getting meningitis.
Treatment of Meningitis
Your treatment is determined by the cause of your meningitis.
Bacterial meningitis requires immediate hospitalization. Early diagnosis and treatment will prevent brain damage and death. Bacterial meningitis is treated with intravenous antibiotics. There’s no specific antibiotic for bacterial meningitis. It depends on the bacteria involved.
Fungal meningitis is treated with antifungal agents.
Parasitic meningitis may either involve treating just the symptoms or attempting to treat the infection directly. Depending on the cause, this type may get better without antibiotic treatment. If it worsens, however, your doctor may try to treat the infection itself.
Viral meningitis may resolve on its own, but some causes of viral meningitis will be treated with intravenous antiviral medications.
Several types of meningitis are not contagious. Fungal, parasitic and non-infectious meningitis are not contagious.
Viral meningitis is contagious. It’s spread through direct contact with body fluids, including mucus, feces, and saliva. Droplets of infected fluid can be spread and shared with sneezing and coughing. You do not have to come into direct contact with an infected person to pick up this infection.
Bacterial meningitis, the most serious form of meningitis, can also be contagious, especially if it’s meningococcal meningitis. It’s spread through extended contact with an infected person. Schools, daycare centers, military barracks, hospitals, and college dormitories are prime locations for sharing this infection. Some types of meningitis are spread through person-to-person contact but not all.
Meningitis in infant
Babies who develop meningitis may show different signs and symptoms of an infection than adults. These symptoms can include:
- body or neck stiffness
- high-pitched crying
- inconsolable behaviors
- sleepy and difficulty waking
- irritable and grumpy
- doesn’t feel well and has a weak suck during breastfeeding
Viral meningitis is common in infants. It develops as a result of colds, cold sores, flu, and diarrhea. The viruses that cause these common conditions also cause viral meningitis.
Bacterial meningitis, which is common but life-threatening, most likely spreads from a serious infection in a nearby area of the body. For example, the bacteria from a severe ear infection or sinus infection can enter the bloodstream and find their way to the brain or spinal cord and cause a bigger infection.
Meningitis in children
Meningitis becomes more common in children as they grow older and reach high school and college ages. Symptoms of viral and bacterial meningitis in children are very similar to symptoms in adults. These include:
- tiredness or fatigue
- sudden fever
- body and neck aches
- confusion or disorientation
Meningitis in adults
The risk for several forms of meningitis decreases after young adulthood. That’s in large part due to changing circumstances. Schools and college dormitories are common sites where some forms of meningitis can be easily shared. Once a young adult ages out of these settings, the likelihood of an infection begins to fall.
However, after age 60, the risk starts to rise again. That’s because of underlying diseases or health conditions that weaken the immune systems in older individuals.
Adults with a compromised immune system are at a greater risk for developing meningitis. Likewise, adults in environments where individuals are in close contact with one another may be at greater risk for an infection. This includes teachers, healthcare providers, daycare staffers.
Vaccine for meningitis
Yes, there is a vaccine for several types of bacterial meningitis. Meningococcal meningitis, caused by Neisseria meningitidis, is one version for which vaccines are available. While viral meningitis is more common, bacterial meningitis can be more dangerous if it’s not diagnosed and treated quickly.
For that reason, the two primary vaccines for meningitis are for bacterial causes. The first vaccine, the meningococcal conjugate vaccine, features a vaccine that targets four of the most common types of bacterial serotypes. It lasts longer and offers greater protection, especially if you maintain booster shots.
The second vaccine, MenB, targets one specific strain, and its protection window is much shorter. Only certain populations are recommended to get this vaccine.
Side effects of a meningitis vaccine include soreness, redness, and burning at the injection site. Some people may experience a low-grade fever for a day or two following the injection. Chills, headache, joint pain, and fatigue are also possible.
Complications from Meningitis
These complications are typically associated with meningitis:
- hearing loss
- vision loss
- memory problems
- migraine headaches
- brain damage
- a subdural empyema, or a buildup of fluid between the brain and the skull
A meningitis infection may produce bacteria in the bloodstream. These bacteria multiply and some release toxins. That can cause blood vessel damage and leaking of blood into the skin and organs.
A serious form of this blood infection can be life-threatening. Gangrene may damage skin and tissue. In rare cases, amputation may be necessary. Several other serious complications may occur in people with meningitis.
Meningitis and pneumonia
Pneumococcal meningitis is a rare but serious and life-threatening form of bacterial meningitis. Even with treatment, 20 percent of people with this type of infection die.
About 40 percent of people carry bacteria called Streptococcus pneumoniae in their throat and the back of the nose. These bacteria are responsible for common illnesses like pneumonia, sinus infections, and ear infections.
From time to time, however, those bacteria manage to cross the blood-brain barrier and cause inflammation and infection in the brain, spinal cord, or fluids immediately surrounding them.
Symptoms of this serious form of meningitis include:
- high fever
- chest pain
Fortunately, two vaccines are available to prevent pneumococcal meningitis.
Risk Factors for Meningitis
The following are some of the risk factors for meningitis:
People with an immune deficiency are more vulnerable to infections. This includes the infections that cause meningitis. Certain disorders and treatments can weaken your immune system. These include:
- autoimmune disorders
- organ or bone marrow transplants
Cryptococcal meningitis, which is caused by a fungus, is the most common form of meningitis in people with HIV.
Meningitis is easily spread when people live in close quarters. Being in small spaces increase the chance of exposure. Examples of these locations include:
- college dormitories
- boarding schools
- day care centers
Pregnant women have an increased risk of listeriosis, which is an infection caused by the Listeria bacteria. Infection can spread to the unborn child.
All ages are at risk for meningitis. However, certain age groups have a higher risk. Children under the age of 5 are at increased risk of viral meningitis. Infants are at higher risk of bacterial meningitis.
These five groups are considered at risk and should get a meningitis vaccine:
- college freshmen who live in dorms and haven’t been vaccinated
- adolescents who are 11 to 12 years old
- people traveling to countries where meningococcal disease is common
- children ages 2 or older who don’t have a spleen or who have a compromised immune system
- Teenagers should protect themselves by getting a meningitis vaccine. Find out when to get your child vaccinated.