Meningitis is an infection of the membranes that cover the brain and spinal cord. It can be caused by viruses, bacteria, or fungi. Viral meningitis is the most common type and usually clears up on its own. Bacterial meningitis is rarer but far more dangerous and requires emergency medical care. You get meningitis when a germ enters your body, usually through your nose or mouth, and travels through the bloodstream to the brain and spinal cord.
What Is the Difference Between Bacterial and Viral Meningitis?
Bacterial and viral meningitis are different diseases with different causes, treatments, and outcomes. The germs that cause them are not the same, and neither are the risks.
Bacterial meningitis is a medical emergency. It can cause brain damage, hearing loss, or death within hours. The most common causes in adults are Streptococcus pneumoniae and Neisseria meningitidis. In newborns, group B Streptococcus and E. coli are more common. Even with prompt treatment, about 1 in 10 people with bacterial meningitis dies.
Viral meningitis is more common and generally milder. Most people recover without specific treatment. The most frequent cause is a group of viruses called enteroviruses, which spread easily in summer and fall. Other viruses like herpes simplex and varicella-zoster can also cause it, though less often.
How Do You Get Meningitis Bacterial Viral More?
Bacteria and viruses that cause meningitis live in the nose, throat, and respiratory tract of some healthy people. You catch them the same way you catch a cold — through respiratory droplets when someone coughs or sneezes, or by touching contaminated surfaces and then touching your face.
Bacterial meningitis is not highly contagious like the flu. You generally need close or prolonged contact with an infected person to catch it. Sharing eating utensils, kissing, or living in the same household are examples of close contact. Casual contact — like sitting next to someone on a bus — rarely spreads it.
Viral meningitis spreads more easily. Enteroviruses can also spread through fecal contamination, especially in childcare settings. Changing a diaper or using a bathroom and not washing hands properly can pass the virus to the next person.
Who Gets Meningitis Most Often?
Anyone can get meningitis, but some groups face higher risk. Children under age 5 are the most likely to get viral meningitis. Bacterial meningitis is most common in infants, teens, and young adults.
Several factors raise the risk of bacterial meningitis:
- Age under 5 or over 60
- A weakened immune system
- Living in close quarters, such as college dorms or military barracks
- Not being vaccinated against meningitis-causing bacteria
- Having a cerebrospinal fluid leak, which can happen after head injury or certain surgeries
- Removing the spleen, which plays a role in fighting certain bacteria
People who have had meningitis once are not immune to getting it again. Different bacteria or viruses can cause repeat infections.
What Are the Early Symptoms of Meningitis?
Meningitis symptoms can appear suddenly. In bacterial meningitis, they often develop within hours. In viral meningitis, they usually build over a day or two.
The classic symptoms are:
- Sudden high fever
- Severe headache that feels different from a normal headache
- Stiff neck that makes it hard to touch your chin to your chest
- Nausea and vomiting
- Sensitivity to light
- Confusion or difficulty waking up
Infants may not show these signs. Instead, they might be irritable, feed poorly, sleep more than usual, or have a bulging soft spot on their head. A high-pitched cry can also be a sign in babies.
Some forms of bacterial meningitis cause a rash. Meningococcal meningitis, caused by Neisseria meningitidis, can produce a rash that does not fade when pressed with a glass. This is a sign of blood poisoning and requires immediate emergency care.
When Should You Go to the Emergency Room?
Bacterial meningitis can progress from mild symptoms to life-threatening illness in less than 24 hours. Do not wait to see if symptoms improve.
Go to an emergency room immediately if you or someone else has a fever with a severe headache and a stiff neck. Add confusion, a rash, or sensitivity to light, and the urgency increases further.
If you are caring for an infant who is lethargic, feeding poorly, or has a bulging fontanel, seek emergency care right away. These signs can mean meningitis or another serious infection.
How Is Meningitis Diagnosed?
Diagnosis requires a lumbar puncture, also called a spinal tap. A doctor inserts a needle between the vertebrae in the lower back and collects a small sample of cerebrospinal fluid. This fluid surrounds the brain and spinal cord.
Lab analysis of that fluid can identify whether the cause is bacterial, viral, or fungal. Bacterial meningitis typically shows high white blood cell counts, low glucose, and high protein in the fluid. Viral meningitis usually shows a moderate white blood cell count with normal glucose.
Doctors may also order blood cultures and imaging scans like a CT of the head before the spinal tap. This is done to check for swelling or other conditions that could make the procedure unsafe.
Treatment often starts before the lab results come back. If bacterial meningitis is suspected, antibiotics are given immediately. Waiting for confirmation can cost critical hours.
How Is Bacterial Meningitis Treated?
Bacterial meningitis requires hospitalization and intravenous antibiotics. Treatment must start as soon as possible. Delays are linked to worse outcomes, including permanent hearing loss, brain damage, and death.
Doctors may also give corticosteroids to reduce brain inflammation. These are most helpful when started before or with the first dose of antibiotics.
People who have had close contact with someone diagnosed with bacterial meningitis may need preventive antibiotics. This is called prophylaxis. It kills any bacteria they may have picked up before symptoms develop. Close contacts include household members, roommates, and anyone who kissed the infected person.
How Is Viral Meningitis Treated?
Viral meningitis does not respond to antibiotics. Most people recover on their own within 7 to 10 days. Treatment focuses on rest, fluids, and pain relief.
Some people with viral meningitis need hospital care. This is more likely in infants, older adults, and people with weakened immune systems. They may need intravenous fluids and monitoring for complications.
Specific antiviral drugs exist for certain viruses. Herpes simplex meningitis can be treated with acyclovir. But for most viral meningitis cases, no antiviral is needed.
Can Meningitis Be Prevented?
Vaccines are the most effective way to prevent bacterial meningitis. Several vaccines protect against the most common bacterial causes.
Vaccines for Streptococcus pneumoniae (pneumococcal disease) are routine for infants and recommended for adults over 65 and people with certain medical conditions. Vaccines for Neisseria meningitidis (meningococcal disease) are given to preteens, teens, and college students. A vaccine against Haemophilus influenzae type b (Hib) is part of routine childhood immunization.
These vaccines do not protect against all causes of bacterial meningitis. But they cover the most common and most dangerous ones.
There is no vaccine for viral meningitis caused by enteroviruses. Good hygiene is the best defense. Wash hands thoroughly after using the bathroom, before eating, and after changing diapers. Avoid sharing utensils, cups, or lip balm with someone who is sick.
Pregnant women should know that listeria, a foodborne bacteria, can cause meningitis. It can also cause miscarriage or severe illness in newborns. Avoiding unpasteurized dairy products and deli meats during pregnancy reduces this risk.
What Are the Long-Term Effects of Meningitis?
Bacterial meningitis has a higher risk of lasting complications. About 1 in 5 survivors is left with permanent problems. These can include hearing loss, seizures, memory problems, and learning difficulties.
Hearing loss is one of the most common complications. Anyone who has had bacterial meningitis should have a hearing test after recovery. Hearing loss can develop weeks or months later.
Viral meningitis rarely causes long-term problems. Most people recover fully. Some report fatigue, headaches, or trouble concentrating for a few weeks after the infection. These symptoms usually resolve on their own.
Frequently Asked Questions
Can you catch meningitis from being in the same room as someone?
Casual contact rarely spreads meningitis. You usually need close or prolonged contact, like kissing, sharing utensils, or living in the same household.
Is meningitis contagious before symptoms appear?
Yes, people can spread the bacteria or virus before they show symptoms. The germs live in the nose and throat and can be passed through respiratory droplets.
How fast do meningitis symptoms appear?
Bacterial meningitis symptoms can appear within hours. Viral meningitis symptoms usually build over one to two days.
Can adults get the meningitis vaccine?
Yes. The meningococcal vaccine is recommended for preteens, teens, and adults at higher risk. Pneumococcal vaccines are recommended for adults over 65 and those with certain health conditions.
