What We Do - Disease Carrying Insects Program - Fairfax County, Virginia

What We Do - Disease Carrying Insects Program - Fairfax County, Virginia

• From May to October, Virginia’s Fairfax County sets about 4,000 mosquito traps with its Disease Carrying Insects Program and then tests the traps for West Nile virus.

Mission: The Fairfax County Disease Carrying Insects Program (DCIP) aims to minimize the impact of mosquito-borne and tick-borne diseases with an integrated approach to pest management including countywide surveillance measures and control practices primarily targeting the most probable vector species in the County, as well as public outreach and education. 

Vector Surveillance

Adult Mosquitoes: Each mosquito season (May to October), the Disease Carrying Insects Program sets nearly 4,000 traps to collect mosquitoes. Many of the mosquitoes collected from these traps are tested for West Nile virus.

Larval (Immature) Mosquitoes: Larval surveillance is used to monitor mosquito "breeding sites" or larval habitats for evaluation and control purposes.  It is important for us to establish mosquito presence and determine which species are present in a larval habitat before control is performed. Mosquitoes are easiest to control in their aquatic larval stage.

Ticks: The DCIP collects ticks and then tests them for pathogens such as Lyme disease.  The tick surveillance data help define public health risk according to tick populations and infection rates of the diseases that they may transmit.

Learn more about tick- and mosquito-surveillance.

Vector Management

Proactive Mosquito Control – Storm drains are treated with a larvicide in three cycles during the West Nile virus season in order to reduce the larval mosquito population of known vector species.  Fairfax County uses a biological larvicide, Bacillus sphaericus, which specifically kills mosquito larvae. The DCIP also encourages County residents to eliminate mosquito larval habitats around their homes, in their communities and neighborhoods.

Reactive Mosquito Control – When routine breeding site inspections on County property indicate high larval (immature) mosquito populations, these areas are treated with a larvicide.  If the risk of West Nile virus transmission is high, the County coordinates larval and/or adult mosquito control measures in public areas as necessary.

Community Outreach

Educating and informing the public is a priority for the DCIP. This is primarily done through risk communication, public education and community outreach. In order to prevent mosquito- and tick-borne disease, it is necessary to equip the County residents and visitors with the knowledge and tools to reduce their risk of contracting a vector-borne disease.

Members of the DCIP staff attend County events, are asked to give presentations to community groups, are interviewed by the press and media, and present research findings at scientific conferences.  We attend over 25 special events and distribute over 20,000 calendars and over 250,000 pieces of educational materials  in seven languages every year!

Program staff investigate and respond to citizens’ concerns and complaints regarding West Nile virus, mosquitoes, ticks and other insect-borne diseases.  Advice is given via phone 703-246-8931 or e-mail, and, in certain cases, home visits are made in order to address and resolve the situation. Learn more about outreach and download free calendars, brochures, and other educational materials.