South Dakota human West Nile disease cases reach 25 The South Dakota Department of Health reported two new human West Nile cases Aug. 31 in residents of Dewey and Moody counties. There have now been 25 WNV disease cases and three blood donor detections reported in South Dakota during the 2004 transmission season. The department also reported a WNV positive mourning dove from Potter County and a pool of WNV positive mosquitoes from Hughes County. West Nile has been detected in 31 South Dakota counties to date.
Twenty-one percent of human cases have been diagnosed with neuroinvasive disease and 79 percent with WNV fever. Sixty-four percent of cases are male and 36 percent female. Eighty-eight percent of cases are white, 8 percent Native American and 4 percent other races. The median age of cases is 42 years with and age range from 9 to 77 year. The elderly are at greatest risk of the most severe form of WNV disease and complications.
"Clearly, the virus is still circulating in South Dakota, as people make their Labor Day plans they should include mosquito repellent on their list of camping, fishing, hiking and picknicking supplies," said Dr. Lon Kightlinger, state epidemiologist.
A testing summary follows:
* Humans: 25 cases (Aurora, Beadle two, Brown four, Butte, Charles Mix two, Codington, Davison, Dewey, Jackson, McCook, Meade, Minnehaha three, Moody, Pennington two, Roberts and Spink counties) and three positive blood donors (Hand, Minnehaha, Tripp). The SD Public Health laboratory has tested 2,254 human blood or spinal fluid specimens for the West Nile virus this year.
* Birds: 68 positive (Beadle one, Brookings two, Brown two, Clark one, Charles Mix one, Davison one, Day 45, Grant one, Hamlin one, Hughes two, Kingsbury one, Lincoln one, Marshall three, Minnehaha two, Pennington two, Potter and Yankton one). Positive bird detections include 45 pelicans, 13 blue jays, five crows, two red-tail hawks, one mourning dove, one kestrel, and one Swainson's hawk. 107 birds have tested negative.
* Veterinary: three positive horses (Brookings, Charles Mix and Pennington), and one positive dog (Turner).
* Mosquitoes: 31,695 mosquitoes tested; 544 positive Culex tarsalis (encephalitis mosquito) and 150 positive Culex pipiens (northern house mosquito) in Beadle, Brookings, Minnehaha and Pennington counties.
* Sentinel chickens: one positive sentinel chicken (Hughes County). 231 tested negative.