What is epidemic encephalitis? What are the clinical manifestations of epidemic encephalitis?

The pathogen of Japanese encephalitis (J-brain) was discovered in Japan in 1934, hence the name Japanese encephalitis. In 1939, Chinese scientists isolated JE virus. After liberation, they carried out a lot of investigation and research work and changed their name to epidemic encephalitis. The disease is mainly distributed in the Far East and Southeast Asia, and is transmitted by mosquitoes, which is more common in summer and autumn. Clinically, the onset of illness, high fever, disturbance of consciousness, convulsions, tonic spasm and meningeal irritation, etc., severe patients often have sequelae after illness, which is a blood-borne disease.

What is epidemic encephalitis? What are the clinical manifestations of epidemic encephalitis?

Epidemic encephalitis clinical manifestations
The incubation period is 10 to 15 days. Most patients have mild or asymptomatic latent infections, and only a few have central nervous system symptoms, which are characterized by high fever, disturbance of consciousness, and convulsions. The course of a typical case can be divided into four stages.

1. Initial stage
Acute onset, body temperature rose sharply to 39 ~ 40 ° C, with headache, nausea and vomiting, some patients have lethargy or mental fatigue, and have a mild neck stiffness, duration of 1 to 3 days.

2. Extreme period
The body temperature continues to rise, reaching more than 40 °C. The initial symptoms gradually worsened, and the consciousness was obviously obstructed, from lethargy, lethargy to coma. The deeper the coma, the longer it lasts and the more serious the condition. Unconsciousness can occur as early as the first 1-2 days of the disease, but it is more common in 3-8 days. In severe cases, generalized convulsions, tonic spasms or tonic spasms may occur, and a few may also be soft. Severe patients may have central respiratory failure due to brain parenchymal lesions (especially brain stem), hypoxia, cerebral edema, cerebral palsy, intracranial hypertension, hyponatremia, etc., manifested as irregular breathing rhythm, double suction Breathing, sigh breathing, apnea, tidal breathing and jaw breathing, etc., and finally stop breathing. Physical examination can detect meningeal irritation, pupils are slow to respond to light, disappear or dilated pupils, abdominal wall and cremaster reflex disappear, deep reflexes, pathological pyramidal tract signs, such as Pap smear can be positive.


3. Recovery period
After the extreme period, the body temperature gradually decreased, and the mental and nervous system symptoms improved day by day. Severe patients are still slow-sick, dementia, aphasia, difficulty swallowing, facial paralysis, toe-twisting or twisting of the limbs, and a small number of patients may also have soft palate. After active treatment, most symptoms can be recovered within six months.

4. Sequelae
A small number of critically ill patients still have neuropsychiatric symptoms after half a year, which are sequelae, mainly conscious disturbance, dementia, aphasia and limb paralysis, epilepsy, etc., if active treatment can have different degrees of recovery. Seizure sequelae can last a lifetime.