Week 31

This week, California reported 49 new humans infected with West Nile Virus (WNV). As of August 5, 2004, a total of 103 WNV infections have been reported from the following local health jurisdictions: San Bernardino (51), Los Angeles (24), Riverside (18), Orange (2), Fresno (2), Kern (2), Tulare (1), and Imperial (1) counties, and Long Beach (1) and Pasadena (1) cities. Five of these WNV infections were initially detected in asymptomatic individuals through screening done at blood banks – one of these individuals later became symptomatic. Of the 99 WNV cases with symptoms, 47 are classified as West Nile fever cases, 43 are classified as West Nile neuroinvasive disease, and 9 are of unknown status. The median age, for all cases where data was available, is 49 years. The median age for West Nile fever cases is 43 years. The median for West Nile neuroinvasive disease case is 57 years. Seventy percent (69/99) of the symptomatic WNV cases are male. There have been two fatalities to date in California. The first occurred in an Orange county resident, and the second occurred in a San Bernardino County resident.