Viral meningitis is a virus-borne inflammation of the meninges, which are the protective membranes surrounding the brain and spinal cord. It’s far less severe than bacterial meningitis, and generally only produces mild symptoms, such as headache, nausea, bright-light sensitivity, and lethargy. But rare cases can cause more severe symptoms. The majority of cases of viral meningitis are due to non-polio enteroviruses. (1) The herpes simplex virus is the second most common cause of viral meningitis in adolescents and adults in developed countries. (2) It’s been estimated that it has an annual incidence of 7.6 per 100,000 adults. (3)
What Causes Viral Meningitis?
There are a number of viruses that can cause meningitis. They include:
EnterovirusesHerpes simplex virus 1 and 2Varicella zoster virus, which causes chickenpox and shinglesEpstein-Barr virusHIVInfluenzaMumpsMeaslesCytomegalovirus meningitis (CMV meningitis)
Only a small number of people infected with enteroviruses will get meningitis. (1) Children younger than age 5 and people with weakened immune systems — from diseases, medication, or recent surgeries or transplants — are most likely to get meningitis from enteroviruses. Infants younger than 1 month old and people with weakened immune systems are most likely to suffer severe symptoms. (1) People who aren’t up to date on their vaccinations may get meningitis from the flu, mumps, or measles.
What Are Other Causes of Viral Meningitis?
Certain insects can also transmit viruses that cause meningitis, such as:
West Nile virus from mosquitoes in certain parts of the Americas, Africa, West Asia, Australia, and mainland EuropeSt. Louis encephalitis virus from mosquitoes in North AmericaEncephalitis viruses from ticks in mainland Europe and Asia
Those who have contact with feces or urine from house mice may get meningitis from the lymphocytic choriomeningitis (LCM) virus. Hamsters and other pet rodents may also carry LCM if they have come into contact with mice. It’s estimated that 5 percent of house mice in the United States carry LCM. (4)
Is Viral Meningitis Contagious?
Yes, but it’s unlikely to spread. While the viruses that cause the disease are generally easily passed between people, viral meningitis itself is not very easily passed between people. When it is, it happens mostly between people who are in regular, close contact. (1,5) Enteroviruses are present in the feces, mucus, and saliva of infected people, and are transmitted through direct contact with an infected person or surface. In temperate climates, these viruses spread most during summer and autumn, and infection rates are high all year long in tropical and subtropical climates. (2) The herpes simplex virus can be passed to other people via contact with an infected area of skin during an outbreak (when the virus is active). Other meningitis-causing viruses are spread in different ways. For instance, mumps, measles, and influenza are easily spread between the unvaccinated through coughing and sneezing, while HIV is spread through unprotected sex and sharing drug needles (since the virus is present in blood, breast milk, and seminal, vaginal, and rectal fluids).
How Long Does Viral Meningitis Last?
Most cases go away on their own within 7 to 10 days. (1) Sometimes recovery can take a few months; this is most likely if the meningitis is caused by West Nile virus or LCM. (6) Regardless, it is important that those who suspect they have meningitis see a medical professional to be properly assessed.
Is Viral Meningitis Fatal?
It can be, but according to the National Meningitis Association, it’s not as deadly or incapacitating as bacterial meningitis. (7) It can be deadly in newborns and those with weakened immune systems.
Can You Get Viral Meningitis More Than Once?
Yes. But it is very rare for a person to have two or more episodes of meningitis because most people develop immunity to the virus that caused their disease. Recurrent viral meningitis is most often caused by herpes simplex 2, and sometimes herpes simplex 1. This type of the disease is called Mollaret meningitis. In order to be diagnosed as having Mollaret meningitis, an individual will have to experience at least three episodes of an illness consisting of a stiff neck, headache, fever, and other meningitis symptoms. (8) These illnesses last about two to five days, then subside on their own.
How Is Viral Meningitis Treated?
If a person is acutely ill, antibiotics will be administered while waiting for test results to confirm whether the illness is bacterial meningitis, which requires immediate treatment. Patients may also be given the antiviral drug acyclovir (Zovirax) if there is a high suspicion that the meningitis is caused by a herpes virus. Once the test results reveal whether the meningitis is viral or bacterial, the drug regimen will be adjusted as necessary.
How Can You Prevent Viral Meningitis?
Vaccines can prevent some types of viral meningitis, though this doesn’t include meningitis caused by enteroviruses. In this case, avoiding close contact with those with enteroviruses and touching your face with unwashed hands can help minimize your chances. If you’re already infected, you can prevent the spread of the virus by frequently washing your hands, disinfecting surfaces, staying away from people, and coughing and sneezing into a cloth or tissue (not your hands). Staying indoors at twilight, using a spray, and wearing long sleeves and long pants will help decrease exposure to mosquito bites, which lead to West Nile and other mosquito-borne viruses. Additional reporting by Carlene Bauer.
