west nile virus activity--united states, october 20-26, 2004. | during october 20-26, a total of 80 cases of human west nile virus (wnv) illness were reported from 16 states (arizona, california, florida, iowa, kentucky, louisiana, michigan, mississippi, missouri, montana, nebraska, new york, ohio, south dakota, texas, and utah). | 2004 | 15514584 |