Note: Single-source report; awaiting corroboration.
The Centers for Disease Control and Prevention (CDC) reports an early start to the 2026 West Nile virus (WNV) season, with 48 human cases by June 30—the highest at this point since 2004. Of these, 38 involved severe neuroinvasive disease affecting the nervous system, surpassing the average of 10 cases typically seen by the end of June since 2004.
This increase is tied to early virus circulation, with WNV activity in 23 states—the most in the past decade. The CDC warns that millions will spend time outdoors during the America's 250th Independence Day weekend, raising the risk of mosquito bites, which transmit WNV.
To reduce infection risk, the CDC recommends using EPA-registered insect repellents, wearing long, loose clothing, avoiding outdoor activity from dusk to dawn, and using window screens or air conditioning to keep mosquitoes out.
State and local health departments continue to monitor mosquitoes and apply control measures. The CDC works with public health partners to provide guidance for reducing infection risk. For up-to-date West Nile virus data, visit the CDC website.
Dr. Erin Staples, CDC medical epidemiologist, emphasized that mosquito season is actively underway and urges the public to take protective steps during holiday gatherings.