Japanese encephalities is also called --------------- and is caused by ---------------Immersive Reader
Answers
Answer:Japanese encephalitis virus JEV is the most important cause of viral encephalitis in Asia. It is a mosquito-borne flavivirus, and belongs to the same genus as dengue, yellow fever and West Nile viruses.
The first case of Japanese encephalitis viral disease (JE) was documented in 1871 in Japan.
The annual incidence of clinical disease varies both across and within endemic countries, ranging from <1 to >10 per 100 000 population or higher during outbreaks. A literature review estimates nearly 68 000 clinical cases of JE globally each year, with approximately 13 600 to 20 400 deaths. JE primarily affects children. Most adults in endemic countries have natural immunity after childhood infection, but individuals of any age may be affected.
Signs and symptoms
Most JEV infections are mild (fever and headache) or without apparent symptoms, but approximately 1 in 250 infections results in severe clinical illness. The incubation period is between 4-14 days. In children, gastrointestinal pain and vomiting may be the dominant initial symptoms. Severe disease is characterized by rapid onset of high fever, headache, neck stiffness, disorientation, coma, seizures, spastic paralysis and ultimately death. The case-fatality rate can be as high as 30% among those with disease symptoms.
Of those who survive, 20%–30% suffer permanent intellectual, behavioural or neurological sequelae such as paralysis, recurrent seizures or the inability to speak.
Transmission
24 countries in the WHO South-East Asia and Western Pacific regions have JEV transmission risk, which includes more than 3 billion people.
JEV is transmitted to humans through bites from infected mosquitoes of the Culex species (mainly Culex tritaeniorhynchus). Humans, once infected, do not develop sufficient viraemia to infect feeding mosquitoes. The virus exists in a transmission cycle between mosquitoes, pigs and/or water birds (enzootic cycle). The disease is predominantly found in rural and periurban settings, where humans live in closer proximity to these vertebrate hosts.
In most temperate areas of Asia, JEV is transmitted mainly during the warm season, when large epidemics can occur. In the tropics and subtropics, transmission can occur year-round but often intensifies during the rainy season and pre-harvest period in rice-cultivating regions.
Explanation: