An Overview Of Meningitis

An Overview Of Meningitis Meningitis is swelling and inflammation of the protective membranes that cover brain and spinal cord. Depending on the duration of symptoms, meningitis may be classified as acute or chronic. Acute meningitis denotes the evolution of symptoms within hours to several days, while chronic meningitis has an onset and duration of weeks to months. Meningitis is mainly caused by infection with viruses, several different types of bacteria, or sometimes by a fungus, and less commonly by certain drugs. Meningitis can be life-threatening because of the inflammation’s proximity to the brain and spinal cord. All types of meningitis tend to cause symptoms that include fever, headache and stiff neck. Knowing whether meningitis is caused by a virus or bacterium is important because the severity of illness and the treatment differ depending on the cause. Viral meningitis, the most common form of meningitis, is less severe than bacterial meningitis. Bacterial meningitis is usually more serious than viral meningitis and is sometimes fatal, particularly in infants and the elderly. Bacterial meningitis is a major cause of death and disability world-wide. [1] b. The etiology and risk factors Meningitis is usually caused by infection from viruses or micro-organisms. Most cases are due to infection with viruses, with bacteria, fungi, and parasites being the next most common causes. It may also result from various non-infectious causes. The etiology of bacterial meningitis varies by age group and region of the world. Worldwide, without epidemics one million cases of bacterial meningitis are estimated to occur and 200,000 of these die annually. [1] Before antibiotics were widely used, 70 percent or more of bacterial meningitis cases were fatal; with antibiotic treatment, the fatality rate has dropped to 15 percent or less. Bacterial meningitis is most common in the winter and spring. Beyond the perinatal period, three organisms, transmitted from person to person through the excha nge of respiratory secretions, are responsible for most cases of bacterial meningitis: Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae. Bacterial meningitis caused by Neisseria meningitidis bacteria (meningococcal disease) can be fatal and should always be viewed as a medical emergency. About 10% of infected people die from the disease. [5] In non-fatal cases, those affected experience long-term disabilities, such as brain damage, loss of limb, or deafness. Preventing the disease through the use of meningococcal vaccine is important. Although anyone can get meningitis, pre-teens and adolescents, college freshmen who live in dormitories and travelers to countries where meningitis is always present are at an increased risk for meningococcal disease. Before the availability of effective vaccines, bacterial meningitis was most commonly diagnosed in young children. Now, as a result of the protection offered by current childhood vaccines, bacterial meningitis is more commonly diagnosed among pre-teens and young adults. As children reach their pre-teen and adolescent years, protection provided by some childhood vaccines can begin to wear off. As a result, pre-teens and adolescents are at a greater risk for catching certain diseases. Introducing vaccinations during the pre-teen years increases the level of protection during adolescence. College freshmen, especially those who live in dormitories, are at a slightly increased risk for bacterial meningitis caused by Neisseria meningitidis bacteria (meningococcal disease) compared with other persons of the same age. vaccination against bacterial meningitis caused by Neisseria meningitidis bacteria (meningococcal disease) is recommended to persons who travel to or reside in countries in which the bacterium Neisseria meningitidis is hyperendemic or epidemic, particularly if contact with the local population will be prolonged.