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Meningitis is an inflammation of the coverings of the brain and spinal cord. Meningitis can be caused by either a virus or bacteria, and correct treatment depends on knowing the difference. Viral meningitis is usually less severe and can heal on its own. Bacterial meningitis, however, can be quite serious, potentially resulting in brain damage, hearing loss, or learning disabilities.
In the 1990s, a vaccine for Haemophilus influenzae type b (Hib), the leading cause of bacterial meningitis, was developed. As a result, the number of cases from these bacteria has been greatly reduced. Also available are vaccines for two other bacteria that cause the disease, Streptococcus pneumoniae and Neisseria meningitidis. Meningococcemia, the form of meningitis caused by Neisseria meningitidis, is particularly deadly.
The early symptoms of viral and bacterial meningitis are quite similar. In adults, they include nausea, vomiting, high fever, severe headache, and sensitivity to light. In infants, symptoms usually are fever, irritability, poor eating, and difficulty waking up. For people with viral meningitis, these symptoms usually disappear within 7 to 10 days. But bacterial meningitis progresses and becomes more serious, causing seizures and coma. Meningococcemia causes additional symptoms—cold hands and feet, muscle and joint pain, rapid breathing, diarrhea, and in later stages, a red or purplish rash. Severe cases of meningococcemia can result in death in a matter of hours.
Bacterial meningitis is treated with antibiotics, typically ceftriaxone and vancomycin. For the best outcomes, it is important to start treatment early in the course of the disease. For viral meningitis, there is no specific treatment. Most people recover on their own from this form of the illness.
Vaccines are the best defense against meningitis. Those that are currently available protect against two of the three most common strains. Young people between the ages of 11 and 18 should be vaccinated. Following healthy habits, such as eating properly and getting plenty of rest, also gives the immune system further protection against meningitis.