Since the beginning of 2012, the CDC (Center For Disease Control and Prevention), has recorded 693 national cases and 26 deaths involving the West Nile Virus.
Symptoms of the West Nile (WN) virus might include headache, fever, body aches and other symptoms. The CDC states that about one in 150 infected people develop a severe illness, while up to 20 percent suffer some other symptoms that might last from a few days to a few weeks. They added that about 80 percent of people infected show no symptoms at all. Symptoms of being infected by the virus usually develop within three to 14 days after being bitten. The CDC adds that people aged 50 and up are more likely to develop more severe symptoms.
Of all the nationally recorded WN virus cases, 406 (59%) were reported as neuroinvasive disease cases and 287 (41%) were reported as nonneuroinvasive disease cases.
The majority of most cases result in neuroinvasive disease, which refers to severe cases that affect a person's nervous system. These include encephalitis which is an inflammation of the brain, meningitis which is an inflammation of the membrane around the brain and the spinal cord and acute flaccid paralysis which is an inflammation of the spinal cord that can cause a sudden onset of weakness in the limbs and/or breathing muscles.Non-neuroinvasive disease cases refer to typically less severe cases that show no evidence of neuroinvasion - primarily West Nile fever. WN fever is considered a notifiable disease, however the number of cases reported (as with all diseases) may be limited by whether persons affected seek care and other factors.
Human disease cases reported to CDC as of August 14, 2012:
For more information, visit the CDC's website at http://www.cdc.gov/ncidod/dvbid/westnile/