Viral meningitis is often less severe than bacterial meningitis and usually resolves without specific treatment. But it can be severe or fatal depending on the virus causing the infection, the person's age, or whether a person has a weakened immune system.
Causes of Viral Meningitis
Most viral meningitis cases in the United States, especially during the summer months, are caused by enteroviruses; however, only a small number of people with enterovirus infections actually develop meningitis.
Other viral infections that can lead to meningitis include:
- Herpes virus, including Epstein-Barr virus, herpes simplex viruses, and varicella-zoster virus (which also causes chicken pox and shingles)
- Viruses spread through mosquitoes and other insects (arboviruses)
- In rare cases, LCMV (lymphocytic choriomeningitis virus), which is spread by rodents
Risk Factors for Viral Meningitis
Viral meningitis can affect anyone. But infants younger than 1 month old and people whose immune systems are weak are at higher risk for severe infection. If you are around someone with viral meningitis, you have a chance of becoming infected with the virus that made that person sick, but you are not likely to develop meningitis as a complication of the illness.
Factors that can increase your risk of viral meningitis include:
- Viral meningitis occurs mostly in children younger than age 5.
- Weakened immune system
- There are certain diseases and medications that may weaken the immune system and increase risk of meningitis. For example, chemotherapy and recent organ or bone marrow transplants.
Transmission of Viral Meningitis
Enteroviruses, the most common cause of viral meningitis, are most often spread from person to person through fecal contamination (which can occur when changing a diaper or using the toilet and not properly washing hands afterwards). Enteroviruses can also be spread through respiratory secretions (saliva, sputum, or nasal mucus) of an infected person. Other viruses, such as mumps and varicella-zoster virus, may also be spread through direct or indirect contact with saliva, sputum, or mucus of an infected person. Contact with an infected person may increase your chance of becoming infected with the virus that made them sick; however, you are not likely to develop meningitis as a complication of the illness.
Signs & Symptoms of Viral Meningitis
Meningitis infection is characterized by a sudden onset of fever, headache, and stiff neck. It is often accompanied by other symptoms, such as
- Photophobia (sensitivity to light)
- Altered mental status
Viral meningitis is an infection of the meninges (the covering of the brain and spinal cord) that is caused by a virus. Enteroviruses, the most common cause of viral meningitis, appear most often during the summer and fall in climates with changing seasons.
Viral meningitis can affect anyone at any age. It is usually less severe than bacterial meningitis and normally clears up without specific treatment, but in some cases viral meningitis can be severe or fatal. The symptoms of viral meningitis are similar to those for bacterial meningitis, which can be fatal. Because of this, it is important to see a health care provider right away if you think you or your child might have meningitis.
Symptoms of viral meningitis may differ depending on age:
Common Symptoms in Infants
- Poor eating
- Hard to awaken
Common Symptoms in Adults
- High fever
- Severe headache
- Stiff neck
- Sensitivity to bright light
- Sleepiness or trouble waking up
- Nausea, vomiting
- Lack of appetite
The symptoms of viral meningitis usually last from 7 to 10 days, and people with normal immune systems usually recover completely. Viruses that cause meningitis can also cause nearby brain tissue infection (meningoencephalitis) or spinal cord infection (meningomyelitis) at the same time.
Diagnosis for Viral Meningitis
If meningitis is suspected, naso-oropharyngeal swabs, rectal swabs, stool, cerebrospinal fluid and blood serum are collected and sent to the laboratory for testing. It is important to know the specific cause of meningitis because the severity of illness and the treatment will differ depending on the cause.
The specific causes of meningitis may be determined by tests used to identify the virus in samples collected from the patient.
Treatment for Viral Meningitis
Usually there is no specific treatment for viral meningitis, but in some instances specific treatment is available depending on the virus (such as herpes virus). Antibiotics do not help viral infections, so they are not useful in the treatment of viral meningitis. Most patients completely recover on their own within 7 to 10 days. A hospital stay may be necessary in more severe cases or for people with weak immune systems.
Prevention of Viral Meningitis
There are no vaccines for the most common causes of viral meningitis. Thus, the best way to prevent viral meningitis is to prevent the spread of viral infections. However, that can be difficult because sometimes people infected with a virus do not appear sick, but they can still spread it to others.
You can take the following steps to help lower your chances of getting infected with a virus or passing one on to someone else:
- Wash your hands thoroughly and often, especially after changing diapers, using the toilet, or coughing or blowing your nose.
- Disinfect frequently touched surfaces, such as doorknobs and the TV remote control.
- Avoid kissing or sharing cups or eating utensils with sick people; avoid sharing with others when you are sick.
- Make sure you and your child are vaccinated on schedule. Vaccinations included in the childhood vaccination schedule can protect children against some diseases that can lead to viral meningitis. These include vaccines against measles and mumps (MMR vaccine) and chickenpox (varicella-zoster vaccine).
- Avoid bites from mosquitoes and other insects that carry diseases that can infect humans.
- Control mice and rats. If you have a rodent infestation in and/or around your home, follow the cleaning and control precautions listed on CDC’s website about LCMV (Lymphocytic choriomeningitis virus).