Overview

• As of Sept. 9, CDC’s ArboNET lists 771 human infections across 39 states, including 490 neuroinvasive cases.
• Officials estimate this pace is about 40% higher than a typical early September and urge EPA-registered repellents, protective clothing, and draining standing water until the first hard frost.
• CDC experts attribute the surge to a greater proportion of infected mosquitoes, with Fort Collins measuring 35 per 1,000 versus 8 expected and Colorado reporting about 150 cases.
• Local reports continue: Suffolk County, N.Y., now has three human cases, and a Delaware County, Pa., firefighter developed brain swelling but has returned to work.
• Elevated activity is also reported in Europe, where nine countries have logged 652 cases and 38 deaths this year, according to the ECDC.