Is Meningitis Contagious?

Inflammation of the meninges is called meningitis.

Meningitis is inflammation of the membranes (meninges) that surround the brain and the spinal cord. The usual signs and symptoms of meningitis are headache, fever, and a stiff neck. There are many types of meningitis. Often meningitis is named according to the cause. For example, there are viral, bacterial, noninfectious (aseptic), and many other types of meningitis.

The contagiousness is related to the specific agent that causes the disease. The following is a summary of five types of meningitis and how they may or may not be contagious.

• Viral meningitis: Meningitis caused by many viruses is usually contagious. However, certain viruses that are transmitted by mosquitoes are usually not spread from person to person, so they are not contagious.
• Bacterial meningitis: Bacterial meningitis is usually contagious; some bacteria are more highly contagious (such as Neisseria meningitidis in young adults and Streptococcus pneumoniae in all ages) than others.
• Fungal meningitis: Fungal meningitis (for example, Cryptococcus meningitis) is not considered to be contagious.
• Parasitic meningitis: Parasitic meningitis, which is rare (for example, Naegleria fowleri), is not considered to be contagious from person to person.
• Noninfectious meningitis: Noninfectious meningitis is not a result of infection but is from an underlying condition or disease and not considered contagious. Causes of noninfectious meningitis include cancers in and around the brain or spinal cord, drugs, head injury, and autoimmune disease (such as lupus or Behçet's disease).

In short, most bacterial meningitis infections are mildly to moderately contagious person to person, while some viral meningitis infections are contagious, but other types are not. Fungal, parasitic, and noninfectious causes of meningitis are not contagious from one person directly to another.

This depends upon which infectious agents are causing the meningitis. In general, when the patient is secreting or producing viruses or bacteria, they are considered contagious. When the patient stops secreting or producing infectious agents is when meningitis is no longer contagious. Viral caused meningitis may be contagious from three days after infection starts to about 10 days after the symptoms develop. Bacterial meningitis is usually less contagious than viral; depending on the bacterial genus causing the infection, it may be contagious during the incubation period and for about an additional 7-14 days. And they can be contagious for much longer (many days to months) if the person becomes a carrier. The contagious period may be shortened with antibiotic treatments.

The incubation period for bacterial meningitis, the most serious types of meningitis, is about three to five days after initial contact with the microbe. However, in some individuals, bacterial meningitis symptoms can occur as rapidly as 24 hours. For viral meningitis, the incubation period can range widely from only a few days to a few weeks. Patients who get meningitis usually have symptoms of headache, fever, and a stiff neck. They may also develop nausea and vomiting, photophobia, and alteration of their mental state. Children with meningitis may appear to be lethargic, drowsy, have a high-pitched cry, may develop a rash, and dislike being held.

Besides the history and physical exam, the physician is likely to do a spinal tap to analyze spinal fluid to detect the agent involved. Bacteria, viruses, or other agents may be identified by subsequent tests of the spinal fluid, including microscopic identification, culture, and immunological tests. In addition, blood and urine samples are also analyzed. Identification of the precise microbe allows the physician to diagnose the type of meningitis and proceed with accurate treatments.

Meningitis spreads to people by many methods. Both bacterial and viral meningitis are spread person to person similarly. Person-to-person spread can happen with direct and indirect contact between individuals (coughing up droplets, contact with the feces, sneezing, saliva, kissing, or eating contaminated food). Indirect spread by using the same utensils, cups, and other items used by an infected individual can also spread the disease to others. Some fungal infections are transmitted by airborne dust particles. In addition, other types of meningitis can be transferred to humans by vectors such as mosquitoes (for example, West Nile virus) or ticks (Lyme disease).

Viral meningitis lasts about 7-10 days with symptoms receding gradually. Bacterial meningitis is usually cured by antibiotics. The time to cure varies with each individual and corresponds with the decrease of symptoms. If bacterial meningitis is not treated rapidly with antibiotics, there can be long-term injury to the brain and even death.

Individuals should contact a medical caregiver immediately about meningitis if they suspect that they have been exposed to bacterial meningitis. Meningitis, especially bacterial meningitis, is considered a medical emergency; if an individual develops early symptoms of meningitis (high fever, headache, and/or neck stiffness) or becomes ill after contacting an individual known to have contagious meningitis, he or she should seek medical care emergently. Bacterial meningitis has about a 10% death rate unless it is treated early in the infection.

Infants with meningitis may develop a firm or bulging soft spot on the head. Other problems that can develop at any age are seizures, altered consciousness, and difficulty breathing. Individuals with these symptoms should immediately go to an emergency department. If an infant or child exhibits such serious meningitis symptoms, if possible, seek a hospital that offers pediatric emergency medicine.