WELD COUNTY, Colo. (KDVR) — Rainfall in the forecast may increase the threat of the West Nile virus across the Front Range.

The Colorado Department of Public Health and Environment confirmed there have been 12 cases in eight counties and one death in Weld County.

Increased rain during hot weather impacts mosquito breeding, which flourishes near standing water.

“Between the amount of mosquitoes, the birds for migration patterns, temperature, it’s very possible that all of this rain has led to water that has more mosquito breeding sites,” Dr. Dan Pastula of UC Health said.

Last year, the CDPHE reported 206 confirmed West Nile Virus cases in Colorado causing 20 deaths.

The Centers for Disease Control reports one out of every five people who contract the West Nile virus will develop a fever and other symptoms.

Less than 1% of those infected develop serious symptoms, but if you notice any changes in your health you should contact your doctor immediately.

To protect yourself, avoid standing water, use repellent and wear pants and long sleeves at dawn and dusk and when enjoying outdoor activities.