encephalitis

noun en·ceph·a·li·tis \ in-ˌse-fə-ˈlī-təs \

|Updated on: 16 Jul 2018

Definition of encephalitis

plural encephalitides play \in-ˌse-fə-ˈli-tə-ˌdēz\

: inflammation of the brain that is caused especially by infection with a virus (such as herpes simplex or West Nile virus) or less commonly by bacterial or fungal infection or autoimmune reaction

Note: Encephalitis may be asymptomatic or present with mild to severe symptoms (such as fever, headache, confusion, seizures, or loss of consciousness) sometimes progressing to coma or death.

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encephalitic

play \in-ˌse-fə-ˈli-tik\ adjective

See encephalitis defined for kids

Recent Examples of encephalitis from the Web

In some individuals, severe illness including meningitis or encephalitis, or even death, can occur.

— jim newton, Lake County News-Sun, "Highland Park area mosquitoes test positive for West Nile virus," 3 July 2018
The film, starring Chloe Grace Moretz, chronicles Cahalan's curious disease, which perplexed doctors, until she was finally diagnosed with anti-NDMA receptor encephalitis, an exceptionally rare autoimmune disease.

— Houston Chronicle, "New Netflix movie explores disease studied by Houston doctor," 2 July 2018
But Keystone virus is one of a group of viruses that are known to lead to encephalitis, or swelling of the brain.

— sarah klein, Health.com, "A Florida Teen Is the First Human to Catch This Virus From a Mosquito," 25 June 2018
Health Department officials said illness from West Nile is usually mild and includes fever, headache and body aches, but serious illness, such as encephalitis and meningitis, and death are possible.

— staff report, Aurora Beacon-News, "Mosquitoes near Elburn test positive for West Nile virus," 15 June 2018
In rare cases, severe illness including meningitis or encephalitis, or even death, can occur.

— alexandra kukulka, chicagotribune.com, "Illinois' first West Nile mosquitoes of the year found in north suburbs," 30 May 2018
There is no known cure for Powassan virus, and about 10 percent of Powassan virus encephalitis cases result in death, according to the CDC.

— gregory b. hladky, courant.com, "Tick-borne Diseases In Connecticut," 6 May 2018
The most serious cases can lead to life-threatening conditions such as meningitis and encephalitis, according to the Johns Hopkins Medicine Health Library.

— hannah holzer, sacbee, "West Nile Virus season has begun: 8 birds have tested positive in Sac County," 25 June 2018
Still, the virus is part of a group found to cause encephalitis in several species, including humans, said the Florida researchers.

— todd ackerman, Houston Chronicle, "Texas officials downplay health threat from little-known mosquito-borne virus that caused symptoms in teen," 23 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'encephalitis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of encephalitis

1843

in the meaning defined above

See Words from the same year

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Medical Dictionary

encephalitis

noun en·ceph·a·li·tis \ in-ˌsef-ə-ˈlīt-əs \

medical Definition of encephalitis

plural encephalitides play \-ˈlit-ə-ˌdēz\

: inflammation of the brain that is caused especially by infection with a virus (such as herpes simplex, varicella zoster, or West Nile virus) or less commonly by bacterial or fungal infection or autoimmune reaction

Note: Encephalitis may be asymptomatic or present with mild to severe symptoms (such as fever, headache, confusion, seizures, or loss of consciousness) sometimes progressing to coma or death.

—