West Nile Virus in the US

Photo by Thomas Kent



Crop-dusting planes are spraying the city of Dallas with insecticide in an effort to kill mosquitoes. It's been a bumper year for mosquitoes, there and elsewhere in the US, and reports of West Nile virus have risen accordingly. 

West Nile aerial attack creates controversy in virus-stricken Dallas | The Lookout - Yahoo! News: 
"43 states have reported West Nile virus infections in people, birds or mosquitoes this year. Twenty-six people have died and nearly 700 have gotten sick.

"The 693 cases reported thus far in 2012 is the highest number of West Nile virus disease cases reported to CDC through the second week in August since West Nile virus was first detected in the United States in 1999," the CDC said in a statement."

The virus produces two illnesses. The first is a mild form with flu-like symptoms called West Nile fever. The second, West Nile encephalitis, occurs when the virus invades the central nervous system. Encephalitis means inflammation of the brain. It can cause such symptoms as headache, fever, stiff neck, tremors, stupor, disorientation, and paralysis. It is sometimes fatal. 



In the terror-obsessed US of the 21st century, the virus has become notorious out of all proportion to its actual danger. The fever afflicts only about 20 percent of those who contract the virus; of that 20 percent, two-thirds of one percent develop encephalitis. Most of those recover. Deaths occur mostly in the elderly. The reservoir for the virus is birds. In the US, robins and crows are among the most commonly infected birds. The virus is transmitted to people by mosquitoes of the genus Culex, especially Culex pipiens.



Photo: A member of the genus Culex, probably C. pipiens. Note that the mosquito is itself infested with parasites. Virtually any animal can host its own brand of mites, maggots, or wasp larvae. Photographer Thomas Kent's Flickr page features many startling and beautiful macro-discoveries.