Encephalitis with meningitis is known as meningoencephalitis. Epidemiology of the disease Infection is the most common cause identified, with viruses being the most important known aetiological agents. Incidence varies between studies but is generally between 3. 5 and 7. 4 per 100,000 patient-years. Encephalitis affects peoples of all ages; however, incidence is higher in the paediatric population. Although both sexes are affected, most studies have shown a slight predominance in males.
Encephalitis occurs worldwide; Causative Agents: Infection by arboviruses specific to rural areas. Infection by enteroviruses (coxsackievirus, poliovirus, and echovirus) in urban areas. Infection by other viruses, including west Nile virus, herpesvirus, mumps virus, human immunodeficiency virus, adenoviruses, and demyelinating disease after measles, varicella, rubella, or vaccination. MODE OF TRANSMISSION.
Transmission by means other than arthropod bites may occur through ingestion of infected goats milk and accidental injection or inhalation of the virus. Incubation Period After 9–12 days, incubation period – mosquitoes transmit disease to other vertebrate hosts. The average life of Culex mosquito is 21 days. Culex can fly over long distances of 4–5 kms. Epidemics occur during monsoon and post monsoon period because the year. CLINICAL SIGNS AND SYMPTOMS: • The signs and symptoms of encephalitis are the same for adults and children.
• Signs and symptoms may last for 2-3 weeks, are flu-like, and can include 1 or more of the following: • Fever ,Fatigue, Sore throat, Stiff neck and back Vomiting, Headache, Confusion, Irritability Unstead gait, Drowsiness, Visual sensitivity to light • More severe cases may involve these signs and symptoms: Seizures, Muscle weakness, Paralysis, Memory loss, Sudden impaired judgment, Poor responsiveness LABORATORY EXAMINATION AND DIAGNOSTIC PROCEDURES Neurological examinations usually reveal a drowsy or confused patient.
Stiff neck, due to the irritation of the meninges covering the brain, indicates that the patient has either meningitis or meningoencephalitis. Examination of the cerebrospinal fluid obtained by a lumbar puncture procedure usually reveals increased amounts of protein and white blood cells with normal glucose, though in a significant percentage of patients, the cerebrospinal fluid may be normal. CT scan often is not helpful, as cerebral abscess is uncommon. Cerebral abscess is more common in patients with meningitis than encephalitis.
Bleeding is also uncommon except in patients with herpes simplex type 1 encephalitis. Magnetic resonance imaging offers better resolution. In patients with herpes simplex encephalitis, electroencephalograph may show sharp waves in one or both of the temporal lobes. Lumbar puncture procedure is performed only after the possibility of prominent brain swelling is excluded by a CT scan examination.
TREATMENT Treatment is usually symptomatic. Reliably tested specific antiviral agents are available only for a few viral agents (e.g. acyclovir for herpes simplex virus) and are used with limited success for most infection except herpes simplex encephalitis. In patients who are very sick, supportive treatment, such as mechanical ventilation, is equally important. Corticosteroids (e. g. methylprednisolone) are used to reduce brain swelling and inflammation.
Sedatives may be needed for irritability or restlessness. NURSING CARE MANAGEMENT Assess the neurologic function; focus on early changes in level of consciousness, Monitor for signs of herniation (abnormal posturing movements, such as decerebration, decortications, and flaccidity, to noxious stimuli). Maintain adequate fluid intake to prevent dehydration. Maintain adequate nutrition. Position the patient to prevent joint stiffness and neck pain.
HEALTH EDUCATION/PREVENTION Wash hands frequently and thoroughly with soap and water, particularly after using the restroom and before and after meals. Don’t share tableware and beverages. Teach your children to practice good hygiene and to avoid sharing utensils at home and school.
Keep your children’s vaccinations current. Before traveling, talk to your doctor’s office about recommended vaccinations for different destinations. < Dress to protect yourself. Apply mosquito repellent. Use EPA-recommended insecticide. Refrain from unnecessary activity in places where mosquitoes are most prevalent. If possible, avoid being outdoors from dusk till dawn, when mosquitoes are most active. < Acyclovir (Zovirax), an antiviral, is prescribed for herpes encephalitis. Anticonsulvant such as phenytoin (Dilantin) is given IV. IV mannitol (Osmitrol) and corticosteroids.