Invasive 'Yellow Fever Mosquito' Reaches Idaho, Sparking Disease Fears

As of November 17th, 2025, the invasive Aedes aegypti mosquito, also known as the 'yellow fever mosquito', has been detected in the state of Idaho for the first time. This aggressive mosquito species, originally from Africa but now found in tropical and subtropical regions worldwide, is capable of spreading several dangerous diseases, including dengue, yellow fever, and Zika.

The Aedes aegypti mosquito was already present in the southern and southwestern United States, but it has been slowly expanding its range. Its arrival in Idaho last September is a concerning development, as these mosquitoes prefer to feed on humans and will bite repeatedly. Coupled with their ability to transmit deadly diseases, the spread of the yellow fever mosquito underscores the need for people spending time outdoors to take precautions.

To protect against Aedes aegypti and other disease-carrying mosquitoes, experts recommend using insect repellent containing DEET, wearing long sleeves and pants, and eliminating any standing water around the home that could serve as breeding grounds. Homeowners should also regularly mow their lawns and remove debris to make the yard less hospitable for mosquitoes. While camping, adding pine needles to campfires can help keep the pests at bay. By taking these preventive measures, people can enjoy the outdoors while minimizing the risk of mosquito-borne illnesses.