s severe and resolves without specific treatment, while bacterial meningitis can be quite severe and may result in brain damage, hearing loss, or learning disability. Meningitis hearing loss typically appears after a bout with meningitis.
Before the 1990s, Haemophilus influenzae Type B (Hib) was the leading cause of bacterial meningitis, but with new vaccines as part of routine immunizations, the occurrence of this invasive disease has reduced. Today, Streptococcus pneumoniae and N. meningitidis are the leading causes of bacterial meningitis. It can be caused by various infectious agents, including viruses, fungi, and protozoa, but bacteria produce the most life-threatening infection. Factors such as age, history of head trauma cerebrospinal fluid leaks, and immune status may help determine the causative agent.
The bacteria that is responsible for meningitis are the meningococcus (N. meningitidis), most important because of its potential to cause epidemics; influenza bacillus (H. influenzae); and various strains of pneumococci, streptococci, or staphylococci. H. influenzae occurs in infants and young children but only rarely in the elderly, and its course and symptoms resemble those of N. meningitidis. In adults, the bacterium pneumococcus (S. pneumoniae) is a common cause of meningitis.
Meningitis hearing loss can range in varying degrees, mild, moderate, severe, profound or total. Though meningitis is a cause of hearing loss, there are others which are congenital or acquired. Hearing loss can be classified by the auditory system that is defective. The causes can be divided into two basic types: conductive and sensorineural hearing loss. Conductive hearing loss is caused by anything that interferes with the transmission of sound from the outer to the inner ear. Possible causes include: middle ear infections (otitis media); collection of fluid in the middle ear ("glue ear" in children); blockage of the outer ear (wax); damage to the eardrum by infection or an