What is blastomycosis and what effects could it have on a pet?
Blastomycosis is an uncommon infectious disease of mammals, including humans, that is caused by the fungus Blastomyces dermatitidis. The fungus is endemic, meaning that it is habitually present in certain areas as a result of permanent local factors in the soil. Northwestern Ontario, from the Manitoba border to about Ignace, is known to be a blasto “hot spot,” as are Georgian Bay from around Britt down to Penetanguishene, and parts of the Ottawa Valley. The fungus appears to thrive in cool, moist, and slightly acidic soils adjacent to waterways where organic debris is present.
For humans, the risk of contracting the disease is very low because most healthy people are resistant to it. Dogs are much more likely than humans to get blastomycosis – and not just those with weakened immune systems. Breeds that nose around the ground, scuff up soil, or disturb it by digging (such as beagles and retrievers) are more likely to contract the disease. In both humans and dogs, the first symptoms tend to be flu- or pneumonia-like: coughing, wheezing, elevated temperature, decreased appetite, and fatigue.
Because the disease is often detected at a later, more acute stage in dogs, it’s important to get your dog treated right away. A dog can die within a couple of days of showing symptoms. Vets who practise in blasto hot spots are usually on the lookout for the disease, but those in other places may never have seen a case of it. It can look like a lot of other things, including kennel cough, allergies, or other respiratory diseases.
Your family doctor may never have seen a case of it either. So if you develop symptoms anytime from a few weeks to several months after a visit to the cottage, get a chest X-ray and have your sputum cultured.