What Is Spinal Meningitis? Here's How People Get This Uncommon but Serious Infection

Spinal meningitis happens when an infection causes inflammation of the membranes (or meninges) that surround the brain and the spinal cord. It's an umbrella term for various kinds of meningitis usually brought on by viruses, bacteria, or other bugs.

While you can recover from some types of spinal meningitis at home, other types can be fatal, so it's important to get treatment right away.

"Meningitis is a very serious infection," Frank Esper, MD, pediatric infectious disease specialist at Cleveland Clinic Children's, tells Health. "It's caused by a bunch of different pathogens, but the two that we deal with here in the United States are either viral or bacterial."

Here's what you need to know about spinal meningitis, including types, symptoms, and what to do if you think you have this illness.

What is spinal meningitis?

Spinal meningitis is a serious infection that can happen to anyone. It causes the meninges, or the thin membranes that protect the brain and spinal cord, to swell. Since those organs control your central nervous system, which is responsible for critical bodily functions like breathing and walking, inflammation in that area is considered a big deal.

Worse yet, some types of spinal meningitis (like the kind caused by bacteria) can become deadly in mere hours, according to the CDC. That's not necessarily true for all types of this infection (viral meningitis, for example, is usually much less severe), but since symptoms alone won't tell you which type you have, it's important to get medical attention ASAP if you show signs of spinal meningitis.

Spinal meningitis symptoms to know

Regardless of which type of spinal meningitis you have and what caused it, the symptoms are often the same, explains Dr. Esper. According to the Mayo Clinic, early symptoms can look like the flu—fever, throwing up, headache, and feeling pretty lousy. As the inflammation worsens, adults may experience other spinal meningitis symptoms, such as:

• Suddenly high fever
• Severe headache that seems different from previous headaches
• Stiff neck
• Nausea or vomiting
• Light sensitivity
• Bleeding under the skin (also called a "meningitis rash")
• Feeling very sleepy or difficulty waking up
• Confusion or limited concentration
• Seizures

"These are symptoms of brain inflammation, not specific to certain germs, whether viral or bacterial," Dr. Esper says. "So, if you have any of these symptoms, that's when we say we're worried about meningitis."

Claire Wright, evidence and policy manager at the UK-based Meningitis Research Foundation, tells Health that the symptoms can come on within a few hours or a couple of days and don't show up in any particular order. Furthermore, not everyone will get the same set of spinal meningitis symptoms.

Parents and caregivers should also be aware that spinal meningitis symptoms can show up a little differently in babies, per the Mayo Clinic. Infants and newborns with meningitis may show symptoms like:

• Constant crying that may worsen when the child is held
• Inability to be comforted
• High fever
• Excessive sleepiness or difficulty waking up
• Irritable mood
• Poor appetite or feeding
• Vomiting
• Stiff body and neck
• Bulging in the soft spot of their head

These are all signs that a baby may need immediate medical care.

How do you get spinal meningitis?

Anyone can get spinal meningitis. In some cases, it can come from a head injury, certain drugs, cancers, lupus, or brain surgery, according to the CDC. But most of the time, people get spinal meningitis after being exposed to specific pathogens, like viruses and bacteria.

Each of these bugs can cause a different type of spinal meningitis, such as:

Viral meningitis

Viruses are the most common culprit behind spinal meningitis, according to the CDC. In the US, infections from non-polio enteroviruses are the pathogen most often responsible for viral meningitis. These bugs are spread in the usual ways, like touching your mouth or nose after touching a contaminated surface or breathing in droplets released when an infected person coughs or sneezes, according to Cedars Sinai.

There are up to 15 million infections from non-polio enteroviruses across the country every year. Most people who catch one only have a mild illness (like the common cold) or don't get sick at all, the CDC notes. Only some of those infections will develop into viral meningitis.

"People get viruses all the time, but viral meningitis, it's really quite rare in comparison to cases of colds," says Wright. "It's not really well known why some people get meningitis or some people just get a cold, even though the infection—the viruses—are the same."

Herpes viruses are the other frequent cause of viral meningitis, and they include herpes simplex (the same virus that causes genital herpes) and varicella zoster, the virus responsible for chicken pox and shingles. This type of spinal meningitis can also come from the same viruses that cause the measles and the flu, per the CDC.

Anyone is susceptible to spinal meningitis from viruses, but kids younger than 5 years old and people with weakened immune systems tend to be at higher risk, according to the CDC. Though each case is different, viral meningitis isn't usually life-threatening. The CDC says that most people who get it recover at home in 10 days or less, no treatment necessary.

Bacterial meningitis

Bacterial meningitis is a very serious illness that can turn deadly quickly. This type of spinal meningitis is caused by bacteria that travel through the bloodstream to the brain, or that enter the meninges directly. Every year, around 3,000 people in the US get bacterial meningitis, according to Boston Children's Hospital.

More than 50 different types of bacteria are thought to cause meningitis, although that number may be a low estimate, according to Paul Auwaerter, MD, MBA, clinical director of the division of infectious diseases at Johns Hopkins School of Medicine. "There are probably all sorts of bacteria that can occasionally cause meningitis, especially if it's after surgical procedures," Dr. Auwaerter tells Health.

Most of the germs that can cause bacterial meningitis are spread from person to person, such as by kissing, or coughing or sneezing in close contact with others, the CDC says. It's also possible for this bacteria to spread through contaminated food or from mothers to babies during childbirth.

According to the World Health Organization (WHO), the typical incubation period for the bacteria that cause meningitis is around four days, but can range anywhere from two to 10.

Like its viral counterpart, bacterial meningitis can affect anyone, but according to the CDC, several groups are at higher risk of contracting the disease, including:

• People who gather in large groups (such as college students on campus)
• Babies
• Travelers to sub-Saharan Africa or Mecca during crowded times
• People with certain medical conditions, including HIV or not having a spleen
• Microbiologists and other professionals who work with bacteria

Because the illness can progress rapidly, anyone suspected of having meningitis should seek immediate medical attention.

The good news is that vaccines can help reduce the risk of certain types of bacterial meningitis. The meningococcal, pneumococcal, and Hib immunizations are all effective at helping to prevent infections, per the CDC. With that said, no vaccine is 100% effective, and anyone—regardless of their vaccination status—should seek care right away if they show signs of meningitis.

Other types of spinal meningitis

While viruses and bacteria cause most spinal meningitis cases, there are a few other pathogens and situations that can lead to this infection.

Breathing in certain fungal spores that live in the environment can cause a rare type called fungal meningitis. Some of these fungi (such as Histoplasma and Blastomyces) live in soil in parts of the US. People with underlying conditions that weaken the immune system, such as HIV or cancer, tend to be at higher risk of spinal meningitis from fungi, according to the CDC.

Though rare, certain parasites can cause meningitis, as well. Typically infecting only animals, people can become infected through eating an animal or through food contaminated by specific parasites. Eating raw or undercooked freshwater fish, for example, could expose you to G. spinigerum parasites, which can cause parasitic meningitis, per the CDC.

Then there's an even more rare type of spinal meningitis from amoeba found in soil and warm water, per the CDC. You can become infected by this amoeba when you're swimming and contaminated water enters your nose. While scary, this type of spinal meningitis has only been reported 148 times in the US from 1962 to 2019, according to the CDC, so it's probably not something you need to lose sleep over.

Not all cases of spinal meningitis come from a pathogen, though. Non-infectious meningitis can occur when the meninges become inflamed due to a disease (like cancer or lupus), medication, head injury, or brain surgery, per the CDC. "Sometimes people start a new medicine, like an antibiotic or even ibuprofen, and occasionally that can precipitate a meningitis," explains Dr. Auwaerter. "The body is reacting against the drug and produces inflammation in the lining of the brain and the spinal fluid."