CDC continues to report cases of West Nile Virus, even this late in the season. Forty-eight states have reported infection in birds, people and/or mosquitoes. As of December 11, 2012, a total of 5,387 cases of West Nile virus disease in people, including 243 deaths, have been reported to CDC. About half the cases were classified as neuroinvasive disease (such as meningitis or encephalitis) and half were classified as non-neuroinvasive disease.
The 5,387 cases reported thus far in 2012 is the highest number of West Nile virus disease cases reported to CDC through the second week in December since 2003. Eighty percent of the cases have been reported from 13 states (Texas, California, Louisiana, Illinois, Mississippi, South Dakota, Michigan, Oklahoma, Nebraska, Colorado, Arizona, Ohio, and New York) and a third of all cases have been reported from Texas.
In addition to case numbers it is also important to look at Incidence Rate or cases per 100,000 people. Note a number of the states listed above which contributed to 80% of the cases had a low incidence rate such as New York and Ohio and other states such as South and North Dakota, Texas, Louisiana, Arizona, and Illinois have high case numbers and high incidence rates.
|WNV Neuroinvasive Disease as of 11 Dec 2012|
|2012||Population||NID cases||Incidence (cases per 100,000 population)|
|District of Columbia||617,996||6||1.0|
Table provided by SD DOH, Dr. Lon Kightlinger, State Epidemiologist