US mosquito populations drop amid West Nile virus concerns

Mosquito populations have decreased significantly across parts of the United States this year. Western and Midwest states, including North Dakota and Minnesota, have seen a 50 percent drop, while levels in Colorado may have fallen by as much as 70 percent.

Experts attribute this decline to historic droughts driven by climate change. However, scientists warn that lower mosquito numbers do not necessarily reduce the risk of contracting mosquito-borne illnesses such as Zika, chikungunya, or dengue.

There is particular concern regarding the West Nile virus, which has reached a 22-year high in case numbers in the U.S. So far this year, 143 cases have been reported, including five deaths in Arizona, which accounts for approximately half of the current cases. High numbers of the virus have also been noted in Colorado.