First Human Case of West Nile Virus Reported in Larimer County
The Larimer County Department of Health and Environment confirmed the first case of West Nile Virus in a Larimer County resident in 2018. A second potential case is under investigation.
The unidentified Fort Collins resident contracted West Nile fever, which develops in about 25 percent of people who contract the virus. This marks the second confirmed human West Nile virus case in Northern Colorado this season.
Trapping mosquitoes to monitor for West Nile virus risk began in June in Larimer County. West Nile disease is a viral infection which is spread to people by bites from infected Culex mosquitoes. Symptoms can range from none at all to severe illness. About 75% of people who are infected are asymptomatic; about 25% will develop West Nile fever. Less than 1% develop the more severe neuroinvasive form, which can lead to hospitalization, critical illness, chronic disability, or even death.
The county health department works with our cities, a mosquito abatement company (Vector Disease Control International, formerly called Colorado Mosquito Control), and Colorado State University experts to monitor and assess the risk to Larimer County residents.
How to Prevent West Nile Virus
West Nile virus can be prevented. In addition to community efforts, such as larviciding, reducing water where mosquitoes can breed, and spraying for adult mosquitoes, individuals can remember to use 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 good 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.