RHHD finds higher risk of transmission of West Nile Virus from mosquitoes in Henrico

HENRICO COUNTY, Va. (WRIC) -- The Richmond and Henrico Health Districts (RHHD) have alerted the public to the increased risk of transmission of West Nile virus in Henrico County following positive tests from mosquito trap sites.

Positive mosquito trap sites in Henrico

RHHD announced on Sept. 19 that, according to Henrico County's Department of Public Works' Vector Surveillance and Control Division, at least 50% of mosquito trap sites tested in the past two weeks have come back positive for West Nile virus.

As of reporting, RHHD said there have been no recent documented human cases of West Nile Virus in Henrico County.

A spokesperson for the health districts explained that mosquito trap sites collect a pool of mosquitoes from a specific area. If one mosquito in a trap tests positive, regardless of how many mosquitoes are in the trap, the trap site is considered positive, according to RHHD.

RHHD and Henrico County consider 50% or more of mosquito trap sites testing positive for the virus for two weeks in a row to indicate a higher risk for transmission of West Nile virus.

What is West Nile virus?

West Nile virus is the most common mosquito-borne disease in Virginia, according to RHHD. People can get the virus after being bitten by an infected mosquito.

West Nile virus cannot, however, be spread through coughing, sneezing or touching, or through eating infected animals or birds.

Most people with a West Nile virus infection reportedly have mild or no symptoms. Those ages 55 and older, and people with certain medical conditions like cancer or kidney disease, are more susceptible to illness and account for most of the serious West Nile virus illnesses, according to RHHD, which can lead to permanent disability or death.

Staying safe

According to RHHD, symptoms of West Nile virus include fever, headache, body aches, vomiting and/or diarrhea, and rash, with rashes occurring in 25 to 50% of cases.

As of reporting, there is no vaccine available for the virus in humans. Mosquito control programs and measures individuals can take to protect themselves are the best way to stay safe from exposure to infected mosquitoes.

In order to protect yourself from mosquitoes, RHHD said to take the following steps:

• 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.
• Consider using an EPA-registered insect repellent on your skin or clothing. 
  • When using insect repellent on children, keep the following in mind:
    • The American Academy of Pediatrics recommends using products containing no 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. 
• Sleep with windows and doors closed unless they are well-screened.

To prevent mosquito habitats on your property, the districts said to take the following steps:

• 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.
  • 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 get advice to limit mosquitoes around their house by filling out this form.

Residents can also visit the Virginia Department of Health website for more information on mosquitoes and mosquito-borne illness.