Tag: mosquito control operations

RHHD Reports Reduced Risk for Transmission of West Nile Virus in Henrico County

October 08, 2025 

Media Contact: Bryan Hooten, 804-807-1727, bryan.hooten@vdh.virginia.gov 

 

RHHD Reports Reduced Risk for Transmission of West Nile Virus in Henrico County 

 

RICHMOND, Va. – The Richmond and Henrico Health Districts (RHHD) reports that the latest surveillance of mosquito trap sites shows reduced risk for transmission of West Nile Virus (WNV) in Henrico County. There have been no recent documented human cases of WNV in Henrico County. 

As of Tuesday, Oct. 7, the percentage of positive mosquito trap sites has dropped below the 50 percent threshold over the last two weeks that would indicate increased risk of transmission of WNV. 

RHHD alerted the public Sept. 19 that Henrico County’s Department of Public Works’ (DPW) Vector Surveillance and Control Division had found that at least 50 percent of mosquito trap sites tested in the past two weeks had returned positive results for WNV. Henrico DPW took immediate action to reduce the risk of transmission of WNV, including: 

  • launching a large-scale, intensified mosquito larvicide operation within County rights-of-way where there was documented high WNV activity; and 
  • increasing trapping and testing efforts to closely monitor the spread of WNV in mosquitoes. 

 

Even though the risk for transmission of WMV has been reduced, members of the public should still take steps to protect themselves from mosquito bites. 

  • Wear loose-fitting and long sleeves and pants and limit the amount of exposed skin when you’re outside in areas where mosquitoes may be active. 
  • The mosquitoes that transmit WNV are most active from dusk until dawn, but they can bite you at any time. 
  • When using insect repellant on children, keep the following in mind: 
  • The American Academy of Pediatrics recommends using products containing no more greater than 30% DEET on children. 
  • Do not use insect repellent on babies under two months of age. 
  • Oil of lemon eucalyptus and para-menthane-diol should never be used on children under three years of age. 
  • Para-menthane-diol is derived from the Australian lemon-scented gum tree, Corymbia citriodora.   
  • Sleep with windows and doors closed unless they are well-screened. 

How to prevent mosquito habitats on your property: 

  • Check outside your residence to be sure there are no containers of standing water. Some mosquitoes lay eggs in containers of water, including containers that only hold about as much water as a bottle cap. 
  • Dump water that collects in containers each week. 
  • Wading pools, ornamental ponds, bird baths, neglected swimming pools, flowerpot trays, buckets and used tires can all serve as sources of standing water for mosquitoes to breed in. 
  • Wash out containers each week before refilling them with clean water.  
  • Mosquito eggs take about one week to hatch. 
  • Cover or store boats or buckets upside down to prevent water from collecting in these containers. 
  • Use mosquito larvicide dunks to regularly treat containers of water that cannot be dumped or drained. 
  • Larvicide dunks kill mosquito larvae in stagnant water sources during warm months when mosquitoes are active. 
  • Follow instructions on the package for correct use. 

Henrico residents can request a free inspection of their property to look for mosquito breeding sites and offer advice to limit mosquitoes around the home. Fill out the inspection form if you are interested. 

West Nile Virus 

West Nile Virus is the most common mosquito-borne disease in Virginia. People can get WNV after being bitten by an infected mosquito. WNV cannot spread through coughing, sneezing, or touching, or through eating infected animals or birds. 

The majority of people with WNV infection have mild or no symptoms. People 55 years of age and older, and people with certain medical conditions such as cancer or kidney disease, are more susceptible to illness and account for most of the serious WNV illnesses, which can lead to permanent disability or death. 

 WNV symptoms include: 

  • Fever 
  • Headache 
  • Body aches 
  • Vomiting and/or diarrhea 
  • Rash (25– 50 percent of cases) 

There is currently no vaccine available for WNV in humans. Mosquito control programs and personal protective measures provide the best protection against exposure to infected mosquitoes. 

Please visit the Virginia Department of Health website for more information on mosquitoes and mosquito-borne illness. Visit rhhd.gov for more health and safety information. Follow RHHD on Instagram (@richmondcity_hd) and Facebook. 

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Mosquito Sample Tests Positive for West Nile Virus in Norfolk

September 18, 2023  

Media Contact: Norman Grefe
Norfolk Health Department, Environmental Health Manager
Norman.Grefe@vdh.virginia.gov
757-683-2824

Mosquito Sample Test Positive for West Nile Virus in Norfolk

NORFOLK, Va. –  The Norfolk Department of Public Health has detected the first West Nile Virus (WNV) activity of the season in the city of Norfolk. One mosquito sample has tested positive for West Nile virus. The sample was collected in the Edgewater/Larchmont neighborhood on September 14, 2023. The Division of Vector Control is conducting mosquito control operations in this neighborhood, including treatments of storm drains and standing water, conducting fogging operations, and continuing surveillance activities.

West Nile Virus is spread to people by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds, and then spread WNV to people and animals by biting them.  Most people infected by WNV do not have any symptoms. When WNV develops into illness, symptoms can include a mild fever, headache, body aches, vomiting, or diarrhea. Serious illness is rare, but more severe symptoms can occur including high fever, severe headache, nausea and vomiting, stiff neck, muscle weakness, confusion, disorientation, paralysis, seizures, or coma. Death occurs in about 10% of persons with serious illness.

Residents are advised to take these preventive steps to help protect themselves and their families from mosquito-borne illnesses:

  • Avoid mosquito bites by using insect repellents when outdoors in mosquito-infested areas. Always ensure that you follow directions on the label.
  • Wear clothing that is long, light, and loose.
  • Home doors and windows should be well-screened to prevent entry of mosquitoes.
  • It is important to eliminate mosquito breeding sites from yards by removing old tires, buckets, tubs, toys, and other items that hold rainwater. Dump ornamental containers (e.g., bird baths) on a weekly basis, or use mosquito larvicide pellets or dunks periodically to treat larger containers (e.g., ornamental ponds, stagnant swimming pools).
  • Clean roof gutters and downspout screens.

For additional information pertaining to mosquito control and surveillance measures, visit our webpage at: https://www.norfolk.gov/5321/Mosquito-Control or call the Vector Control Division at (757) 683-2840, weekdays from 7:00 a.m. to 3:30 p.m.