India is facing a national emergency with the outburst of Japanese encephalitis in states like West Bengal, Bihar and Uttar Pradesh killing mainly children and infants. Its death toll has gone up to 61 in West Bengal and 350 deaths in Uttar Pradesh.

What is encephalitis?

The term encephalitis means inflammation of the brain. The inflammation is mainly caused by a virus and it is most common in infants, young children, elderly and people with weakened immune system for e.g. people suffering from cancer or HIV disease etc.

What causes encephalitis?

Encephalitis can be caused by viral infection or by several other viruses like polio, rabies virus, varicella zoster or commonly known as chicken pox virus, mumps, rubella, adenovirus, cytomegalovirus, West Nile virus, and echovirus.

Types of encephalitis

Encephalitis can be largely divided into four main types depending on the mode of its transmission. They are as follows:

• Herpes Simplex encephalitis: It is caused by Herpes simplex virus type 1 or HSV-1.
• Japanese encephalitis: It was first identified in Japan and named after the yellow fever virus or flavivirus. It is transmitted through Culex mosquitoes.
• West Nile encephalitis: It is also spread through mosquitoes and characterized by high fever. It is caused by a virus belonging to the Flaviviridae family.
• Tick borne encephalitis: It is caused by viruses spread through ticks.

Other causes of encephalitis: It can also be caused if there is allergies to any particular vaccination, autoimmunity, or parasitic infection.

Transmission of the virus

• Consumption of contaminated food or water.
• Inhalation of respiratory droplets exhaled by an infected person.
• Coming in direct contact with an infected person.
• Bites from insects like ticks or mosquitoes.

Symptoms of encephalitis

There are some common symptoms through which one can easily detect encephalitis. They are as follows:

• Headache.
• Stiffness in the neck and the back.
• Disorientation.
• Confusion.
• Seizures.
• Weakness in arms and legs.
• Altered consciousness.
• Sometimes there may be fever.

Diagnosis of encephalitis

• Brain Scans: Magnetic Resonance Imaging (MRI), Computerized Tomography (CT) scan are done to evaluate the extent of inflammation as well as it allows to differentiate encephalitis from other conditions.
• EEG or electroencephalogram: It helps to detect abnormal patterns of activity including epileptic seizures by recording the brain waves.
• LP or lumbar puncture: Here the doctor takes a sample of the CSF or cerebrospinal fluid.

Treatment of encephalitis: Treatment of encephalitis is done in accordance to the symptoms. Hepes simplex encephalitis is treated with acyclovir. Corticosteroids are used to reduce brain inflammation and swelling. Patients are kept in ICU and they often require ventilation support. They may also receive sedatives to reduce restlessness. Due to the outbreak of Japanese and tick-borne encephalitis in India vaccinations are now available. Children are mostly susceptible to this virus due to their low immune system and it is always prudent to give them vaccination if they are found to have a weak immune system.

Prevention and control of encephalitis in India

In India encephalitis mostly occur during the monsoons. It is spread by mosquitoes and ticks. In West Bengal and North Bengal this year there has been an outbreak of Japanese encephalitis. Uttar Pradesh and Bihar are also some states where every year there is an outburst of encephalitis mainly effecting the malnourished children. To control encephalitis proper preventive measures should be followed especially in the infection-prone areas. 

Preventive measures for children:

• Wearing full sleeves and full pants while playing outside in parks.
• Always use mosquito nets while sleeping and close windows during sleep.
• Insecticides should be sprayed regularly in schools, playgrounds, and residential areas.
• Apply mosquito repellent ointments in exposed areas of children.
• Keep houses and residential areas clean.
• Most important, vaccination should be given to children requiring so as early as possible.

Encephalitis is life threatening and children suffering from symptoms should be immediately taken to emergency care. Proper hygiene and prevention care should be undertaken in order to control this disease.