Late July surveillance along Nampa-Caldwell Boulevard caught a single Aedes aegypti in a CO2-baited trap, marking only Idaho’s second known detection of the invasive mosquito.
Four outside entomologists confirmed the find, but Canyon County officials said one mosquito does not prove a local population has taken hold.
Crews have already treated nearby breeding sources and adult mosquitoes, added species-specific traps, and asked residents reporting daytime bites to submit locations to help target surveillance.
Aedes aegypti breeds in tiny water-filled containers—down to a bottle cap—and its eggs can survive dry transport in items like tires, buckets and plant shipments.
Officials said the species is likely being carried into Idaho by vehicles or goods rather than migrating naturally, though warmer sheltered sites such as storm-drain vaults could help it survive winters.