Coconino County Health and Human Services (CCHHS) officials found mosquitoes that tested positive for West Nile virus (WNV) in an area south of Lake Mary Road in Flagstaff. This is the first positive WNV in mosquitoes in Coconino County this year. No human cases have been reported in Coconino County since 2010 when two human cases were identified.
CCHHS staff has applied a non-toxic larvicide treatment to reduce mosquito populations in water pools in the affected area and in other locations in the County. CCHHS will continue trapping and testing mosquitoes in areas where there is mosquito activity until colder weather returns. Although this is the only area where mosquitoes have tested positive this year, WNV is endemic and could be present in other areas throughout the County.
According to the Centers for Disease Control and Prevention, insect repellent containing DEET, Picaridin, Oil of Lemon Eucalyptus or PMD -the synthesized version of oil of lemon eucalyptus, and IR3535 typically provide reasonably long-lasting protection.
People are encouraged to take the following precautions to prevent mosquito bites. • Mosquitoes that carry WNV are most active at dusk and dawn. Stay indoors during these times or wear shoes and socks, long pants and a long-sleeved shirt when outdoor. • Use screens on windows and doors. Repair holes in screens to keep mosquitoes outdoors. • Use air conditioning, if available. • Stop mosquitoes from laying eggs near your home. Once a week, empty and scrub, turn over, cover, or throw out items that hold water, such as tires, buckets, planters, toys, pools, birdbaths, flowerpots, or trash containers.
People should continue these preventive measures until cold weather returns and mosquito activity diminishes in the fall. There is no specific treatment for WNV other than supportive care, and there is no vaccine available for humans. A WNV vaccination is available for horses. CCHHS encourages horse owners to discuss vaccinations with their veterinarian.
For more information or to report any concerns, call the Coconino County Health and Human Services Environmental Health office at 928-679-8750 or toll free 1-877-679-7272.