Many different viruses can cause this form of meningitis. The most common is a group called enteroviruses. There are approximately 80 different types of enteroviruses. They usually have no noticeable effect or may result in mild cold and flu symptoms such as sore throat, nasal congestion and stiffness. Only rarely do they cause meningitis. Even so, enteroviruses cause about half of all viral meningitis.
Enteroviruses are contagious. They spread from person to person by direct contact with saliva, sputum, nasal mucus, or stool. Toddlers and young children who put toys in their mouths, share food and utensils are susceptible. Intimate contact, such as kissing, spreads these viruses. So does touching something an infected person has handled, then rubbing your own nose, mouth or eyes. Changing diapers of infected children can also spread enteroviruses.
Of all people infected with enteroviruses, less than 1 in 1000 develops meningitis. The symptoms have a wide range of severity. They can be very mild with a fever and headache. Such cases probably would not be seen by a doctor and would not likely be diagnosed. In severe cases, symptoms include rashes, a stiff neck, sore throat, nausea and vomiting. There may also be abdominal pain, aches and pains in muscles and joints. Sometimes viral meningitis causes confusion and altered consciousness. People with severe symptoms should seek medical assistance.
Mumps and measles viruses can cause meningitis. They can also cause encephalitis. In this case the brain itself is infected. Encephalitis is serious. Fortunately, mumps and measles viruses rarely cause either disease any more because most children are routinely given MMR (measles, mumps, rubella) vaccinations and boosters.
Herpes simplex virus (HSV) is one of the most common viruses infecting humans of all ages. We may carry the virus with occasional flare-ups of cold sores from HSV-1. HSV-2 is the cause of genital herpes. HSV can cause meningitis and encephalitis. Encephalitis from HSV is more common and more severe than meningitis, but both infections happen rarely.
Arborviruses are a large group of viruses found, as its name suggests, in forests. Mosquitoes and ticks are the most common carriers. They spread the viruses among wild animals and birds and their bite can also infect humans. A few of these viruses cause meningitis or encephalitis in humans, but rarely. St Louis Encephalitis virus has occurred in Canada. It can be severe, even fatal. Outbreaks usually occur in the summer when tick and flea populations peak.
Almost all people infected with viral meningitis recover completely within 5 to 10 days. However, symptoms such as recurrent headaches, fatigue, dizziness may persist for several months. Rarely is there any permanent damage or lasting effects. There are no treatments for viral meningitis. Antibiotics have no effect on viruses. Patients with severe symptoms can be made more comfortable as the disease runs its course.
A rare form of viral meningitis may result in recurrent attacks of fever, headache, stiff neck, muscle aches, vomiting. The frequency of recurrent attacks varies widely. The most common cause of recurrent viral meningitis (called Mollaret Syndrome) is Herpes Simplex Virus. Treatment with antiviral drugs active against Herpes simplex virus may prevent recurrences.