Public health officials in Sudbury have confirmed the presence of West Nile virus in a crow found in the Espanola area, marking the first positive case in a bird since last year and prompting renewed calls for residents to take protective measures against mosquito bites. Early warning sign Public Health Sudbury & Districts announced the positive test result in a news release Monday, confirming that an American crow in the Espanola area has been infected with West Nile virus. Rachel O’Donnell, an Environmental Support Officer at Public Health Sudbury & Districts, explained the significance of the finding to CTV News. “When we see West Nile virus birds test positive, it’s an early warning sign just to tell us that West Nile is active in the local environment. So, it’s important for people to take precautions,” she said. The last infected bird reported in the area occurred last year, making this year’s confirmation a notable development for public health surveillance. Human cases rare Jonathan Groulx, a manager also with the local public health authority, provided context on recent human cases. “The last person confirmed to have been infected with West Nile virus infection in our area was in 2023,” he said. According to health officials, most individuals who contract the virus experience no symptoms at all, but some may develop mild reactions including fever, headache, body aches, mild rash, and swollen lymph glands. “In a very small amount of people, we would see what’s called West Nile Encephalitis, which is brain swelling and damage that can be very serious,” said O’Donnell. Despite these risks, officials emphasize that the overall threat to humans remains low. Transmission cycle Dr. Fiona Hunter, a professor of medical and veterinary entomology at Brock University, offered her perspective on the current situation, noting that this year does not appear to be one of significant concern. “There are a few years where we have had a lot of human cases. In those years, we have had lots of mosquitoes test positive,” she said. “The good news is this is not one of those years.” Hunter said the fundamental nature of West Nile virus, describing it as primarily a bird disease. A mosquito can acquire the virus by biting an infected bird and then transmit it when the mosquito seeks its next blood meal, which is commonly another bird. While most mosquito species that feed on birds tend to restrict themselves to avian hosts, some species are less discriminating in their feeding habits. “They’re not quite so picky,” said Hunter. “They will pick the infection up from an infected bird, and then the next meal, pass it on, potentially to a mammal and that could include us.” Protecting oneself In response to the confirmed case, local health officials have issued a series of recommendations for residents to reduce their exposure to mosquitoes and minimize the risk of infection. The health agency advises residents to repair and use screens on windows and doors to prevent mosquitoes from entering homes. Standing water around properties should be removed, as these areas serve as breeding grounds for mosquitoes. Residents are also encouraged to wear light-coloured clothing, which is less attractive to mosquitoes and to use approved insect repellent when spending time outdoors. These precautions are particularly important during peak mosquito activity periods, typically dawn and dusk, though health officials recommend maintaining protective measures throughout the day as well. Public health officials said they will continue to monitor the situation through ongoing surveillance of bird and mosquito populations.
