CDC warns early West Nile surge, highest since 2004

Health officials across multiple states are warning of an early and severe start to the West Nile virus season, with the U.S. Centers for Disease Control and Prevention reporting the highest national activity since 2004. As of late June, at least 48 human cases had been reported nationwide, a significant increase from the typical average of 10 cases by that point in the summer.

The virus, transmitted through the bite of an infected mosquito, has been detected in mosquitoes from numerous counties. In California, Placer County announced its first positive mosquito samples of the year on Wednesday, collected from agricultural and residential areas. This follows the state's first reported human infection in Sacramento County last week. The Sacramento-Yolo Mosquito Vector Control District has reported increased activity since May, with 24 positive mosquito samples and 40 dead birds testing positive across Sacramento and Yolo counties. Separately, Ventura County confirmed its first mosquito sample of the year tested positive, collected in Fillmore last month.

Outside California, Mississippi confirmed its first human case of the year in Hancock County. In New Jersey, Atlantic County...