What is meningitis?

Meningitis is a central nervous system infection. If meningitis is suspected, hospital admission is arranged quickly so that intravenous antibiotic treatment can start immediately and without waiting for a firm diagnosis.

Broad spectrum antibiotics are used to target different types of bacteria, and a spinal tap is also done to culture the bacteria causing the infection so that antibiotic treatment can be more individually tailored to the infection.

Viral meningitis cannot be treated using antibiotics. Because it is less severe than bacterial meningitis, viral meningitis can be treated by anti-viral drugs, corticosteroids to reduce inflammation, or just with pain killers to reduce the worst of the aches and pains.

Many cases of viral meningitis eventually resolve without treatment.

Treating encephalitis and other central nervous system infections

Encephalitis is always extremely serious and fast treatment and supportive care is essential.

Illness caused by herpes viruses can be treated using anti-viral drugs such as acyclovir or foscarnet. Inflammation caused by other viruses cannot be treated and care focuses on reducing symptoms and their impact on the brain.

Brain abscesses are also very serious and are usually fatal unless treated. Treatment consists of an antibiotic for up to 6 weeks.

If the abscess does not shrink, a neurosurgeon may recommend an operation to drain it.

A central nervous system infection can affect anyone

Although the true incidence of central nervous system infection is not known, it is thought to be relatively common:

• Bacterial meningitis affects up to 7 out of every 100,000 adults, with a similar rate in children
• The most common form of meningitis is viral, accounting for around 40% of central nervous system infections and occurring in up to 219 out of every 100,000 children aged under one year
• Meningitis is most common in young children, adolescents, and people over 55 years old. However, meningitis epidemics can affect anyone of any age
• Bacterial meningitis is also associated with a high risk of death: around 10–30% of cases are fatal
• Encephalitis can affect anyone, although young children and the elderly have the highest risk. Unfortunately, encephalitis is associated with a high death rate. Japanese encephalitis virus, for example, can be fatal in up to 60% of patients within one week of infection. Acute viral encephalitis can also result in coma and long-term mental problems
• Brain abscesses are very rare, but are associated with a high fatality rate unless treatment is administered quickly