Week 35

Weekly Update Humans West Nile Virus A total of 12 human cases of West Nile virus (WNV) illness were reported this week from 8 counties: Butte (1), Fresno (1), Kern (2), Los Angeles (2), Riverside (2), San Bernardino (1), San Diego (1), and Tulare (2). These are the first WNV human cases reported from Riverside County this year. In 2019, 57 WNV human cases have been reported from 12 counties. Of the 57 reported cases, 34 (60%) were classified as neuroinvasive disease and 2 (3.5%) fatalities have been reported. The median age of the individuals is 58 years (range: 15–93 years) and 35 (61%) are male. Dates of symptom onset range from May 12 to August 17. In addition to the 57 cases, 14 asymptomatic infections have also been reported from Butte (1), El Dorado (1), Kern (3), Madera (1), San Bernardino (4), San Joaquin (1), Shasta (1), Stanislaus (1), and Sutter (1) counties. At this time last year, 42 human cases of WNV illness had been reported from 18 counties.