Meningitis

It 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 are viral and bacterial infections. Other causes may include:

• Chemical irritation
• Cancer
• Drug allergies
• Fungi

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

What are the symptoms?

The symptoms of viral and bacterial meningitis can be similar in the beginning. However, bacterial symptoms are usually more severe. The symptoms also vary depending on your age.

Viral meningitis symptoms

In infants may cause:

• Decreased appetite
• Sleepiness
• Lethargy
• Irritability
• Fever

In adults, may cause:

• Fever
• Headaches
• Stiff neck
• Seizures
• Sensitivity to bright light
• Sleepiness
• Lethargy
• Nausea and vomiting
• Decreased appetite

Bacterial meningitis symptoms:

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. Your doctor will need to perform tests to determine which type you have.

Fungal meningitis symptoms

Symptoms of this resemble the other types of this infection. These may include:

• Nausea
• Vomiting
• Sensitivity to light
• Fever
• Headache
• Confusion or disorientation

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.

Types:

Viral and bacterial infections are the most common causes. There are several other forms. Examples include cryptococcal. which is caused by a fungal infection, and carcinomatous, which is cancer-related. These types are less common.

Viral meningitis

It is the most common type. Viruses in the Enterovirus category cause 85%  of cases. These are more common during the summer and fall, and they include:

• Coxsackievirus A
• Coxsackievirus B
• Echoviruses

Viral meningitis typically goes away without treatment. However, some causes do need to be treated.

Bacterial meningitis

It is contagious and caused by infection from certain bacteria. It’s fatal if left untreated. Between 5-40% of children and 20-50% of adults with this condition die.

Fungal meningitis

It is a rare type. 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 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 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

This 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

This is not an infection. Instead, it is a type that’s caused by other medical conditions or treatments. These include:

• A head injury
• Brain surgery
• Cancer
• Certain medications