- The Norfolk Department of Public Health’s Vector Control Division is engaged in mosquito control and surveillance activities on a year-round basis. The goal is the reduction of mosquito populations for protection from the threat of mosquito-borne disease, as well as betterment of quality of life for Norfolk residents. Vector control employs a multi-faceted approach to help manage mosquitos and rodents that includes surveillance, control, and education. Please report any problems with mosquitoes online here or call our office at: 757-683-2840.
- Mosquitoes are a nuisance, but they also transmit diseases. The most common mosquito borne diseases are West Nile Virus and Eastern Equine Encephalitis but they can also carry:
What We Do
Surveillance
Vector Control begins with surveillance. We conduct dipping surveys to locate mosquito larva and samples are taken to identify species. Adult mosquito surveillance is carried out using three trap types:
- CDC Light Trap: This trap is designed to target adult mosquitoes in search of a host to feed on. It consists of a hanging trap and net. The CDC light trap uses a light and a source of CO2 to attract mosquitoes.
- CDC Gravid Trap: Gravid traps are used to collect female mosquitoes that are seeking a water source to lay eggs. The mosquitoes collected in these traps carry the highest risk of being infected with a mosquito borne disease. The trap is a toolbox with a fan and collection net that sits over a pan of water.
- BG Sentinel Trap: This trap is used for Asian tiger (Aedes albopictus) mosquito surveillance. It sits on the ground and uses CO2 and a specially formulated lure to attract mosquitoes looking for a host to feed on.
If you see any of our traps placed throughout the city, please feel free to observe them in action but do not disturb them. They provide us with the valuable information to target areas of high mosquito populations and mosquito borne disease.
Mosquitoes collected from our traps are tested for West Nile Virus and Eastern Equine Encephalitis. Disease surveillance is also conducted using sentinel chicken flocks. Female chickens placed in secure coops throughout the city are sampled every other week to test for infection of West Nile Virus or Eastern Equine Encephalitis. Surveillance data allow mosquito control personnel to make informed, scientifically based decisions as to the most appropriate interventions.
Control
Mosquito control consists of two approaches: targeting mosquito larvae (source reduction and larviciding) and adult mosquitoes (adulticiding.)
- Source Reduction: The most important and most effective method of mosquito control is source reduction! This means eliminating the water that mosquitoes need to complete their life cycle. If we can reduce the amount of stagnant water, we can reduce the number of mosquito larva that can hatch into adults. Source reduction can be accomplished by turning over containers that hold water, i.e., buckets, flowerpots, tarps, toys, pools, tires, and other man made containers. Source reduction is accomplished on a larger scale through maintenance of tidal ditches to remove stoppages that could cause water to pool.
- Larviciding: Water sources that can’t be eliminated can be treated with chemicals that prevent the growth of mosquito larvae. Vector Control uses chemicals that specifically target mosquitoes and minimize harm to other aquatic organisms. Residents of the City of Norfolk can also purchase products that they can use to treat standing water on their property to prevent mosquitoes. Large bodies of water contain natural predators that prevent mosquitoes.
- Adulticiding: Ultra-low-volume (ULV) truck mounted sprayers are dispatched to control the adult mosquito population. ULV spraying is conducted based on our surveillance to ensure we are targeting the areas that need adult control. The chemicals are dispensed at a rate that is safe for the environment and citizens but still effective in killing mosquitoes.
What You Can Do
- Mosquitoes in the city of Norfolk thrive in our urban environment. The average home provides plenty of opportunities for mosquitoes to lay eggs. Mosquitoes only need a teaspoon of water to complete their life cycle and hatch into adults. It is important for residents to regularly survey their homes, yards and neighborhoods for standing water. If water can be eliminated, please do so. Containers that hold water can produce a sizeable mosquito population that can be a real nuisance to the neighborhood. Protect your health by decreasing the chances of contracting a mosquito transmitted disease. You can avoid mosquito bites by using a repellent that contains DEET, Picardin or Oil of Lemon Eucalyptus. Make sure you follow the label directions. Avoid times when mosquitoes are most active during dawn and dusk. Please report areas of standing water or problems with mosquitoes to MyNorfolk or call us at: 757-664-6510.