Overview: West Nile virus confirmed in a Greater Sudbury horse
Public Health Sudbury & Districts has confirmed that a horse in the Greater Sudbury area tested positive for West Nile virus. This marks the third animal in the region to test positive this year, following two crows that were found positive in the summer. The last reported human case in the area occurred in 2023. Health officials emphasize that while the risk to people remains low, the late summer and early fall period is when transmission risk tends to rise due to higher mosquito activity.
The One Health approach: interconnecting human, animal, and environmental health
Ontario’s One Health framework highlights how animal health, human health, and the environment influence one another. By monitoring West Nile virus across humans, wildlife, and mosquito populations, public health authorities, veterinarians, healthcare providers, and environmental experts can better predict, prevent, and respond to outbreaks. The appearance of the virus in a horse underscores the need for vigilance across sectors, especially in late summer when mosquitoes are most active.
How West Nile virus spreads and what it means for people
West Nile virus is transmitted through the bite of an infected mosquito. It cannot be spread directly from horses to humans or between other animals. Most people infected with the virus show no symptoms. Some experience fever, headache, body aches, mild rash, or swollen lymph nodes. In very rare cases, infection can affect the brain and cause severe illness. While the risk to the general public is low, taking precautions during peak mosquito season remains important.
What to watch for in horses and how to protect them
Early signs of West Nile virus in horses can include fever, muscle twitching, hypersensitivity to touch or sound, and difficulty standing. Vaccination and boosters are a key preventive measure for horses. Ensuring horses are up to date with vaccines can significantly reduce the risk of severe disease.Horse owners should discuss vaccination status with their veterinarian and follow veterinarian-approved guidance on repellents and general care during mosquitoes’ peak times.
Practical steps to reduce West Nile virus risk at home
Public Health officials offer straightforward measures to lower exposure to mosquitoes around homes and properties:
- Reduce mosquito breeding sites by removing standing water around the property.
- Install or repair window and door screens to keep mosquitoes out of indoor spaces.
- Avoid outdoor activity at dusk and dawn when mosquitoes are most active.
- Wear light-colored, long-sleeved shirts and pants, and apply approved insect repellent as directed.
Precautions for horse owners and stabling routines
To protect horses, owners should consider keeping stables prepared during mosquito-prone times. Strategies include basing horses in environments where fans deter mosquitoes and applying veterinarian-approved repellents as advised by a veterinary professional. These precautions, along with vaccination, can help mitigate risk for horses during late summer and early fall.
Where to get reliable information
For more details about West Nile virus and local guidance, contact Public Health Sudbury & Districts at 705.522.9200 or toll-free at 1.866.522.9200, or visit phsd.ca. For information specific to horses, reach out to your veterinarian or local public health authorities.
In Ontario, ongoing collaboration among public health teams, veterinarians, and environmental experts remains essential to monitoring West Nile virus activity and protecting both human and animal communities. The statement from Jonathan Groulx, manager of Public Health Sudbury & Districts’ Health Protection division, emphasizes vigilance: “Although the overall risk of a person becoming infected remains low, late summer and early fall are typically the time of greatest risk for contracting West Nile virus as mosquitoes can carry higher levels of the virus at this time of year.”
Contact information
For more information about West Nile virus and local health updates, contact Public Health Sudbury & Districts at 705.522.9200 or visit phsd.ca.
