Meningitis

Meningitis is a serious infection or inflammation of the meninges or membranes of the brain or spinal cord. Meningitis can be classified according to organisms which causes the infection like bacteria (bacterial meningitis), viruses (viral meningitis), fungi (fungal) etc. and also according to the membranes effected. Bacterial or acute meningitis is the most severe form which is commonly caused by three types of bacteria such as Meningococcal (Neisseria meningitidis), Haemophilus influenzae type B and Pneumococcus (Streptococcus pneumoniae). 

Meningococcal meningitis is the more common meningitis among children under 4 years with greatest risk for babies about six months of age and young adults in the age group of 15-20 years. The bacteria inhabits the back of the throat and mouth and is spread by coughing and sneezing. Only some people who are exposed to the bacteria are susceptible to infection while others become carriers of the bacteria but remain well.  

Symptoms
The incubation period for meningitis is usually between two and five days and may be up to 10 days. Symptoms may include:

• Sore throat

• Runny nose

• Discomfort

• Vomiting

• Severe head ache and stiff neck

• Fever and rash

• Intolerance of light

• Drowsiness, unconsciousness and coma

A high-pitched cry, refusal of feeds, vomiting and convulsions  are the signs of meningitis in infants. 

Infants can become severely ill with in a few hours and there should be no delay in seeking medical attention. The bacteria enters the blood stream and multiplies at a very high rate releasing toxins that causes the onset of early symptoms like sore throat, runny nose, lethargy followed by severe symptoms as illness progresses very rapidly.

Adverse effects
Bacterial meningitis can prove fatal with in a short span of time. Meningococci bacteria can cause Septicaemia (blood poisoning) along with meningitis. Septecaemia can cause damage, inflammation and disintegration of the walls of the blood vessels leading to bleeding or fall in blood pressure and the development of shock. Patients who do recover from the disease, occasionally has the risk of long term brain damage, hearing loss, mental retardation, occurrence of fits etc.

Diagnosis  
Early diagnosis is based on symptoms. A lumbar puncture or spinal tap to obtain a sample of cerebrospinal fluid will be done for confirming the infection and to find out the causative organism. The type of bacteria responsible for infection should be identified to give the correct Antibiotics treatment. 

Treatment
Recovery from the infection is more likely if treatment begins early in the course of the disease. If meningitis is suspected, immediate hospitalisation and a broad spectrum antibiotic, usually penicillin injections effective against the common meningitis bacteria is given even before the test results are known. Further treatment is based on the causative bacteria responsible. In addition patient will be isolated and measures to control fever and pain, lots of fluid and electrolyte replacement therapy will be given.  People who are in close contact with the patient are also recommended to take oral antibiotics (one dose or a very short course) to prevent further spread.

A vaccine is available for meningitis caused by Haemophilus influenza type B (hib) and this is normally given to babies along with dpt vaccination at 2, 3 and 4 months. Vaccines are also there for meningococcal (for one strain of the bacteria) and Pneumococcus bacterial infections. But this is not effective for the group which is most at risk i.e. children below 2 years. The pneumococcal meningitis is the most common type of meningitis in adults so pneumococcal vaccine is recommended for all persons over 65 years of age and younger persons with certain chronic medical problems.