Special to the Surveyor

The Larimer County Department of Health and Environment (LCDHE) is once again alerting the public that there is an unusually high abundance of mosquitoes that can carry West Nile virus in Berthoud. The Health Department has notified town leadership to recommend immediate spraying of affected areas and urges all residents and visitors to take extra precautions to prevent mosquito bites.

The most recent mosquito traps in Berthoud indicate a Vector Index (VI) over 3.0. The VI is a measure of the level of West Nile Virus (WNV) infected mosquitoes in an area. A VI above 0.5 strongly predicts cases of WNV in humans and a VI above 1.0 is clearly correlated with human cases. Thus, the recent mosquito traps are more than two times the threshold of where human cases would be expected to occur.

Town of Berthoud leadership has informed LCDHE that a special town board meeting will be held on Tuesday, July 18, 2023, to consider spraying for adult mosquitoes. This is the second week in a row with an elevated VI and the town increased larviciding last week.

“We are seeing unprecedented levels of mosquitoes in Berthoud that can carry West Nile virus,” says Tom Gonzales, Larimer County Public Health Director. “We have communicated with Town leadership and are urging that they spray affected areas immediately to prevent human cases of the virus, which can be very serious for some people.”

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.

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.

The Health Department is asking all residents and visitors to 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.
• 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.

For more tips on what you can do to prevent West Nile virus, visit www.larimer.gov/westnile.