What is meningitis?

Meningitis is an inflammation of the meninges. The meninges are the three membranes that cover the brain and spinal cord. Meningitis can occur when fluid surrounding the meninges becomes infected.

What is meningitis?

Meningitis is an inflammation of the meninges. The meninges are the three membranes that cover the brain and spinal cord. Meningitis can occur when fluid surrounding the meninges becomes infected.

The most common causes of meningitis are viral and bacterial infections. Other causes may include:

Some viral and bacterial meningitis are contagious. They can be transmitted by coughingsneezing, or close contact.


What are the 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.

Viral meningitis symptoms

Viral meningitis in infants may cause: decreased appetite irritability sleepiness lethargy fever In adults, viral meningitis may cause: headaches fever stiff neck seizures sensitivity to bright light sleepiness lethargy nausea and vomiting decreased appetite

Bacterial meningitis symptoms

Bacterial meningitis symptoms develop suddenly. They may include: altered mental status nausea vomiting sensitivity to light irritability headache fever chills stiff neck purple areas of skin that resemble bruises sleepiness lethargy 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.

Fungal meningitis symptoms

Symptoms of fungal meningitis resemble the other types of this infection. These may include: nausea vomiting sensitivity to light fever headache confusion or disorientation

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

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 echoviruses Viruses in the Enterovirus category cause about 10 to 15 million infectionsTrusted Source 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 HIV measles herpes viruses Coltivirus, which causes Colorado tick fever Viral meningitis typically goes away without treatment. However, some causes do need to be treated.

Bacterial meningitis

Bacterial meningitis is contagious and caused by infection from certain bacteria. It’s fatal if left untreated. Between 5 to 40 percentTrusted Source of children and 20 to 50 percentTrusted Source 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.

Non-infectious meningitis

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: lupus a head injury brain surgery cancer certain medications