The Larimer County Department of Health and Environment is alerting residents and visitors to the heightened risk of West Nile virus in Larimer County. There is currently an unusually high abundance of mosquitoes that can carry the virus, which was detected in some mosquitoes this week in Larimer County. The Health Department is urging extra precautions be taken to prevent mosquito bites when outdoors.

In Fort Collins, Loveland, and Berthoud there has been 10 times and more than what is expected for Culex mosquito abundance based on historical averages. Culex mosquitoes, particularly Culex tarsalis species that are being found in Larimer County mosquito traps, are very efficient at transmitting West Nile virus. 

“The number of Culex mosquitoes we’re seeing is very concerning and potentially dangerous. It is likely that we’ll see more human cases of West Nile virus this summer than we’ve seen in previous years,” says Tom Gonzales, Larimer County Public Health Director. “However, West Nile virus is preventable, and I urge residents and visitors to take extra precautions to avoid mosquito bites over the Independence Day holiday and throughout the summer.”

West Nile disease is a viral infection spread to people through bites from infected Culex mosquitoes. The symptoms of West Nile disease can vary widely, from no symptoms to severe illness, and generally appear between 3-14 days after infection. The most common symptoms include fever, nausea and vomiting, muscle weakness and aches, rash, and headaches.

In addition to community mitigation efforts, individuals can practice the 4 D’s to help prevent West Nile virus disease:

• Defend – Use DEET or other effective mosquito repellent - Use an EPA-registered mosquito repellent that has been proven to be effective against West Nile virus-carrying mosquitoes.  DEET, Picaridin, Oil of Lemon Eucalyptus (also called p-menthane-3,8-diol or PMD), and IR3535 are effective choices.

• Dusk to Dawn - Avoid exposure during peak Culex mosquito feeding times, from dusk through dawn.

• Dress - Wear long sleeves and pants to keep mosquitoes from biting.

• Drain – Remove standing water in your yard or garden to minimize mosquito breeding areas.

The Larimer County Department of Health and Environment closely monitors West Nile virus prevalence in the community through partnerships with municipalities, a mosquito abatement company (Vector Disease Control International), and Colorado State University to monitor and assess the risk to Larimer County residents.  

For more tips to prevent West Nile virus, visit www.larimer.gov/westnile.