GC: n

S: CDC – https://www.cdc.gov/west-nile-virus/about/index.html (last access: 16 August 2024); WHO – https://www.who.int/news-room/fact-sheets/detail/west-nile-virus (last access: 16 August 2024).

N: 1. – West (adj): As an adjective from late 14c.; as a noun from late 12c. West used in geopolitical sense from World War I (Britain, France, Italy, as opposed to Germany and Austria-Hungary); as contrast to Communist Russia (later to the Soviet bloc) it is first recorded in 1918. West Coast of the U.S. is from 1850; West End of London is from 1776; West Side of Manhattan is from, 1858. The U.S. West “western states and territories” originally (1790s) meant those just west of the Alleghenies; the sense gradually extended as the country grew. To go west “die” was “common during the Great War” [OED, 2nd ed.], perhaps from Celtic imagery or from the notion of the setting sun. In U.S. use, in a literal sense “emigrate to the western states or territories,” from 1830.

– Nile (geographical name): river in Africa, one of the world’s oldest surviving place names, from a Semitic root nahal “river.” Unnamed in Old Testament, it is always merely “the river” (Hebrew yeor).

– virus (n): late 14c., “poisonous substance” (a sense now archaic), from Latin virus “poison, sap of plants, slimy liquid, a potent juice,” from Proto-Italic *weis-o-(s-) “poison,” which is probably from a PIE root *ueis-, perhaps originally meaning “to melt away, to flow,” used of foul or malodorous fluids, but with specialization in some languages to “poisonous fluid” (source also of Sanskrit visam “venom, poison,” visah “poisonous;” Avestan vish- “poison;” Latin viscum “sticky substance, birdlime;” Greek ios “poison,” ixos “mistletoe, birdlime;” Old Church Slavonic višnja “cherry;” Old Irish fi “poison;” Welsh gwy “poison”).

The meaning “agent that causes infectious disease” emerged by 1790s gradually out of the earlier use in reference to venereal disease (by 1728); the modern scientific use dates to the 1880s. The computer sense is from 1972.

2. West Nile virus, virus belonging to the family Flaviviridae, related to viruses that can cause yellow fever and dengue and more closely to viruses that can cause encephalitis (inflammation of the brain). Predominantly an infection of birds, West Nile virus is highly fatal for many avian species (e.g., crows and other corvids). A threat to human health occurs when infected birds are bitten by mosquitoes, which then transmit the virus to humans.

3. West Nile virus historically was largely confined to Africa, the Middle East, and parts of Russia, India, and Indonesia, where it caused occasional, usually minor, epidemics of denguelike illness or sporadic encephalitis. However, the virus eventually was imported more broadly into Europe by migratory birds, and in 1999 it reached the United States, emerging in New York City, where it was detected in both birds and people. The virus subsequently was isolated from mosquitoes in Connecticut, and antibodies were detected in horses in Connecticut and New York state. West Nile virus also spread into Canada and the Caribbean and, later, to most other U.S. states.

4. In humans, infection with West Nile virus causes a flulike illness known as West Nile fever. Most human infections are inapparent or mild, with illness that usually lasts only a few days. However, in a minority of infected persons, particularly in those over age 50, the virus multiplies in the lymphoid tissue and circulates in the bloodstream (possibly also multiplying in leukocytes, or white blood cells) before penetrating the central nervous system (CNS). In the CNS, depending on which tissues are infected, the virus can give rise to any of various conditions classified as West Nile neuroinvasive disease. In some instances, the virus reaches the brain, resulting in West Nile encephalitis, symptoms of which include headache, fever, neck stiffness, disorientation, and muscle weakness. Death may result. Alternatively, spread of the virus to the CNS can cause West Nile meningitis, a distinguishing symptom of which is stiff neck, or West Nile poliomyelitis, a syndrome characterized primarily by acute flaccid paralysis.

5. Microbiology and Parasitology; Viral Diseases: West Nile virus.

• The mosquito-borne virus that causes West Nile fever.
• The West Nile virus is one of the flaviviruses, a family of viruses also responsible for dengue, yellow fever, and tick-borne encephalitis virus.

6. West Nile virus is transmitted by mosquitos and causes an illness that ranges from mild to severe. Mild, flu-like illness is often called West Nile fever. More severe forms of disease, which can be life-threatening, may be called West Nile encephalitis or West Nile meningitis, depending on where it spreads.

S: 1. Etymonline – https://www.etymonline.com/search?q=West+Nile+virus (last access: 16 August 2024); MW – https://www.merriam-webster.com/dictionary/Nile (last access: 16 August 2024). 2 to 4. EncBrit – https://www.britannica.com/science/West-Nile-virus-disease (last access: 16 August 2024). 5 & 6. TERMIUM PLUS – https://www.btb.termiumplus.gc.ca/tpv2alpha/alpha-eng.html?lang=eng&i=1&srchtxt=VIRUS+NIL+OCCIDENTAL&codom2nd_wet=1#resultrecs (last access: 16 August 2024).

SYN:
S:

CR: culicine mosquito, mosquito, virus, West Nile encephalitis, West Nile fever.