Encephalitis is mostly caused by viruses though bacterial encephalitis is also reported at times.
Thousands of cases go undetected because symptoms are latent in quite a good number of affected people.
Types of Encephalitis
There are two kinds of encephalitis.
- Primary encephalitis
- Secondary encephalitis
Primary encephalitis: In primary encephalitis where the virus directly attacks the brain and the spinal chord, may be either focal or diffused. In focal encephalitis the infection is confined to an area where as in the diffused encephalitis the infection is present over a wider area.
Secondary encephalitis: It is also known as post infective encephalitis for the infection occurs due to current viral infection of the body.
Acute Disseminated Encephalitis: It is a kind of secondary viral infection that occurs due to an already present viral infection or even immunization.
Causes of Encephalitis
In the United States most of the cases of viral encephalitis are caused by the following means:
- Herpes simplex virus types 1 and 2
- Bite from a rabid animal (rabies virus)
- Lyme disease(bacterial infection spread by tick bite)
Risk of Encephalitis
Anyone can be at risk of getting encephalitis. People in whom immune system is deficient and those who are taking immunosuppressant form the highest rick group.
Transmission of Encephalitis:
Some forms of encephalitis are contagious and they are generally transmitted by the following modes:
- Contact with saliva
- Nasal discharge
- Respiratory and throat secretions
Symptoms of Encephalitis
The symptoms of the encephalitis include the following:
- Other neurological symptoms
More severe symptoms of encephalitis include the following:
- Nausea and vomiting
- Confusion and disorientation
- Sensitivity to bright light
- Poor appetite
Other Relevant Symptoms of Encephalitis
Other relevant symptoms that are associated with encephalitis include the following:
- Mild flu-like symptoms
- Problems with speech or hearing
- Double vision
- Personality changes
- Loss of consciousness
- Loss of sensation in some parts of the body
- Muscle weakness, partial paralysis in the arms and legs
- Sudden severe dementia
- Impaired judgement
- Memory loss
Signs and Symptoms in Infants
The important symptoms that one needs to watch for in infants include the following:
- Body stiffness
- Constant crying (worsens when the child is picked up)
- Full or bulging fontanel (the soft spot on the top of the head)
Diagnosis of Encephalitis
Diagnosis of Encephalitis include the following methods
- Physical Examination
- Enquiring previous history
The Neurological Examination of Encephalitis
The neurological assessment of the encephalitis include the following:
- Motor and sensory function
- Nerve function
- Hearing and speech
- Coordination and balance
- Mental status
- Changes in mood or behaviour
Clinical Diagnostic Techniques
Clinical Diagnostic techniques that are used for detecting the causative organism include the following:
- Laboratory screening of blood, urine, and body secretions
- Antibodies and foreign proteins identification tests
- Throat culture : Samples of throat culture are taken in the physician’s office or in a laboratory setting and sent for analysis to state laboratories or to the U.S. Centers for Disease Control and Prevention. Results are usually available within few days.
- Analysis of Cerebro Spinal Fluid (CSF)
Other Diagnostic Techniques for Encephalitis
Other Diagnostic techniques include the following:
- Computer assisted tomography
- Magnetic Resonance Imaging (MRI)
- Electroencephalography (EEG)
Treatment of Encephalitis
Antiviral drugs used to treat viral encephalitis include acyclovir and ganciclovir.
Supportive Care for Associated Symptoms of Encephalitis
The following supportive care is generally given for managing the symptoms of Encephalitis:
- Bed rest
- Over-the-counter analgesics to treat headache
Prevention of Encephalitis
The following measures are generally recommended for preventing the Encephalitis:
- Maintain good personal hygiene.
- Avoid sharing food, utensils, glasses, and other objects with a person exposed to infection.
- Wash hands often with soap and rinse under running waste.
- Use mosquito repellent, nets and clothing with longer sleeves.
- Remove water from outdoor areas such as lawns and free-standing pools of waste.
- Limit outdoor activity during nights.
Prognosis for Encephalitis
Outcome generally depends on the particular infectious agent involved, the severity of the illness, and how quickly treatment is given. In most cases, people with very mild encephalitis or meningitis can make a full recovery, although the process may be slow.
Patients who experience mild symptoms such as headache, fever, and stiff neck recover in few weeks. Patients receiving treatment for viral encephalitis usually experience some relief within few days and recover in one month.
The patients of encephalitis may need long-term therapy, medication and supportive care to make recovery from encephalitis.