West Nile Virus

West Nile Virus is a disease mainly spread to people through an infected mosquito’s bite. Mosquitoes can become infected by feeding on the blood of birds that carry the virus. Not all mosquitoes carry West Nile Virus. The virus does not spread from person to person.

The Brant County Health Unit controls West Nile Virus (WNV) in Brantford and the County of Brant by monitoring mosquitoes in various sources of standing water around the community. We treat catch basins and storm water management ponds with pesticide in order to reduce the number of mosquitoes.

Find more information about WNV below:

Year Total number of pools tested Number of Positive Pools Number of Human Cases
2020 180 1 1
2021 196 2 0
2022 196 0 0
2023 196 1 0
2024 Testing in progress* 0 0

*Stats are relevant as of June 5, 2024.

While 70-80% of people who are infected with West Nile Virus are asymptomatic, mild symptoms include:

  • fever
  • headache
  • body aches
  • mild rash
  • swollen lymph glands

Symptoms can appear within 2-15 days of infection.

Individuals who are immunocompromised, 50 years or older, pregnant, or young children are at greater risk of experiencing severe symptoms of West Nile Virus.

Less than 1% of people will develop severe symptoms. However, serious infections can target the central nervous system, which affects the brain and spinal cord.

Serious symptoms can include:

  • sudden severe headaches
  • high fever
  • stiff neck
  • nausea or vomiting
  • difficulty swallowing
  • drowsiness
  • confusion

In extreme cases, symptoms include:

  • loss of consciousness
  • lack of coordination
  • muscle weakness
  • paralysis

If you experience West Nile Virus symptoms after receiving a mosquito bite, contact your health care provider immediately. 

For mild cases, recovery takes about a week. Severe cases carry a variety of health effects that can last for months or even years. In extreme cases, West Nile Virus can be fatal.

The best way to reduce the risk of West Nile Virus infection is to prevent mosquito bites.

When you are outside at dawn and dusk, cover exposed skin with the following:

  • long pants and long sleeved, loose-fitting shirts
  • socks
  • hat (consider mosquito nets over your head)
  • light-coloured clothing (dark colours attract mosquitos)
  • insect repellents, including bug sprays and lotions, that contain the DEET chemical.

Mosquitos lay eggs in standing water. Standing water is when water sits still and does not move or circulate for more than 48 hours.

Examples of standing water include:

  • Bird baths that are not emptied and refilled at least every 48 hours
  • Pools that are filled and not circulating
  • Rain barrels with no screen cover
  • Blocked eavestroughs

Mosquitoes can develop in any puddle that lasts more than 7-10 days during the summer.

Swimming Pools:

  • Open your swimming pool by mid-June at the latest and keep the water circulating and treated with adequate sanitizers such as chlorine or bromine products, even if it is not being used.
  • Keep your pool cover drained of rainwater. You can purchase a small pump to empty the water into a drain or your yard. You can also treat the water with a mosquito larvicide available to the public. This product is called AquaBac, and is carried by various hardware stores.
  • If you do not plan to open your pool, cover it with a solid covering such as plywood to prevent mosquitos from accessing the water in the pool.
  • Turn over plastic wading pools when they’re not being used.
Ornamental Garden Ponds:
  • Always use a pump to continuously circulate the water.
  • Stock your pond with fish, frogs, or water bugs that will feed on mosquito larva. You must use a pump along with the fish to keep the water moving.
  • If you no longer wish to maintain the pond, fill it in or drain and cover it with a tight-fitting tarp or solid material such as plywood.
  • Dispose of unwanted tires at the local landfill site.
  • Cover old tires with a tarp to prevent water from pooling inside them.
  • Drill holes in the bottom of the tires to allow rainwater to drain out.
Rain Barrels:
  • Keep rain barrels covered with a small mesh screen to prevent mosquitoes from laying eggs in the water.
  • Empty rain barrels if the water is more than a week old.
Bird Baths:
  • Change water every other day.
  • Clean the eavestroughs regularly to ensure the water flows through them and does not remain stagnant.
  • Make sure eavestroughs are installed on a slight angle, allowing the water to flow to the downspout.
Outdoor Containers:
  • Cover any garbage, recycling or composting containers to prevent water from accumulating in them.
  • Store items upside down or drill holes in the bottom of containers that must be left outdoors like flowerpots, gardening cans, and wheelbarrows.
  • Use landscaping to eliminate water that collects in low areas on your property.

Some birds, including crows and jays, may become infected and die from West Nile Virus. To report a bird who may have died from WNV, phone the Canadian Cooperative Wildlife Health Centre at 1-866-673-4781.