West Nile Virus-Moninder Dhillon B

Description of virus that causes the disease.

• The West Nile virus is a type of virus known as a flavivirus. Researchers believe West Nile virus is spread when a mosquito bites an infected bird and then bites a person

Viral Specificity:

• West Nile virus has birds as a host and horses as a reservoir. Occasionally humans are infected and die.
  This disease has been encountered in horses in the United States.
• It primarily attacks the Central Nervous System, But once it's in your body, you will have systemic symptom, like a fever, shivering, fatigue.

Symptoms and progression of the disease:

• WNV has three differnet effects on humans. The first is an asymptomatic infection; the second is a mild febrile syndrome termed West Nile Fever; the third is a neuroinvasive disease termed West Nile meningitis or encephalitis.
• Mild disease, generally called West Nile fever, may cause some or all of the following symptoms:
  
  Abdominal pain
  Diarrhea
  Fever
  Headache
  Lack of appetite
  Muscle aches
  Nausea
  Rash
  Sore throat
  Swollen lymph nodes
  Vomiting
  
  These symptoms usually last for 3 - 6 days.

• More severe forms of disease, which can be life threatening, may be called West Nile encephalitis or West Nile meningitis, depending on what part of the body is affected. The following symptoms can occur, and need prompt attention:
  
  Confusion or change in ability to think clearly
  Loss of consciousness or coma
  Muscle weakness
  Stiff neck
  Weakness of one arm or leg

Common Methods of Transmission:

(Pictures/flowchart/graphic organizer if possible)

• The virus is transmitted through mosquito vectors, which bite and infect birds. The birds are hosts, developing sufficient viral levels to transmit the infection to othe biting mosquitoes which go onto infect other birds
• In mammals the virus does not multiply as readily, and it is believed that mammals do not ingest enough virus to become infected, and making it a so-called dead-end infections

Treatment and Prevention:

• Human illness from West Nile virus is rare, even in areas where the virus has been reported.
• The chance that any one person is going to become ill from a mosquito bite is low
• There is no permanent cure but AMD3100, which is a drug for HIV has showed promise against West Nile Encephalitis.
• There is a Horse vaccine to kill the Virus called West Nile-INNOVATOR
• West Nile control is achieved through mosquito control, by eliminating mosquito breeding sites and encouraging personal use of mosquito spray

Miscellaneous:

• Mosquitos can run up to 1.5mph and can smell you or another host from 20-35 metters away
• So if you run fast enough to put more than that distance between you and the mosquito, then hopefully it will lose your signal and give up the chase and you wont get West Nile Virus.
• West Nile virus was first isolated and identified as a distinct pathogen from the blood of a woman in the West Nile region of Uganda in 1937
• Why isn't there a human vaccine, but a Horse one?
• In Canada, 42 people have died from the virus since 2002.
• You never know if the mosquito has the disease so be sure to always put repellent on!

Resources accessed:

(At least two) ||
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004457/
http://en.wikipedia.org/wiki/West_Nile_virus
http://www.cdc.gov/ncidod/eid/vol6no4/rappole.htm
http://www.westnilevirusfacts.org/