“This is a special dog,” says Fred Kampo of Oshkosh, Wisconsin, referring to the black Labrador Retriever he calls “Stinger.”
While everyone likes to think his or her Lab is special, Kampo’s perspective is broader than most. A member of the Retriever Field Trial Hall of Fame, inducted in 2012, Kampo is president of The Labrador Retriever Club, the American Kennel Club parent club of the Labrador Retriever.
Last summer, FC-AFC B Bumble was on a serious roll. In June, the 6-year-old male, who had earned more points over the course of his career than any retriever his age or younger actively competing in field trials, churned through 10 grueling series to become one of 13 finalists from a starting field of 110 at the National Amateur Retriever Championship in Stowe, Vermont. A few weeks later in mid-July, Stinger topped a field of 82 in a hotly contested open all-age stake at the Mississippi Headwaters Retriever Club in Bemidji, Minnesota.
Two days after that impressive win – two days — this elite canine athlete could barely walk. Stinger was diagnosed with blastomycosis, a fungal infection that can occur systemically or locally, laying even the most robustly healthy dog low and sometimes with devastating, even deadly, consequences.
“The lameness was his first symptom,” says Kampo, who’s handled Stinger to the majority of his field trial wins. “There’d been no coughing or respiratory difficulty of any kind, which I’m told is typically the first sign a dog may have ‘blasto.’”
In Stinger’s case, the disease had attacked several of his vertebrae, and because his spinal cord was at risk, all off-lead activities were immediately curtailed. Crate confinement and walking on leash became the order of the day for the next five months.
Following an initial 10-day period in which he received the fungicidal drug itraconazole (ITZ) intravenously, Stinger was put on a daily oral dosage of ITZ. It had been a frighteningly swift fall from the top of the field trial world, but it could have been much worse.
Triggered by a Wet Environment
Blastomycosis is caused by a fungal mold, Blastomyces dermatitidis, associated with moist, slightly acidic soil and decomposing organic matter, such as wood and leaves. The mold releases microscopic spores into the air, and when these spores are inhaled, infection can result.
“When the spores get way down into the lungs is when it creates a problem,” says Alfred M. Legendre, DVM, DACVIM, an infectious disease specialist at the University of Tennessee College of Veterinary Medicine.
The warm, moist environment of a dog’s lungs triggers a transformation of the spores into a yeast that can spread via the bloodstream or the lymphatic system to other parts of the body. Although rare, blastomycosis also can occur when spores are introduced to an open wound.
“Blastomyces is a pretty big organism in yeast form,” explains Dr. Legendre. “The yeast is too big to get down deep into the lungs to cause disease.”
The condition is not contagious. “It doesn’t spread dog to dog, or dog to person,” Dr. Legendre says. “When dogs and their owners have simultaneously developed blasto, it is because they were exposed to the spores at the same time.”
Dogs and humans are the most commonly infected species, with dogs 10 times more likely to develop the disease than humans. Geographically, blastomycosis is most prevalent in the valleys of the Mississippi, Ohio and St. Lawrence rivers, the Great Lakes states and certain parts of Canada. According to the Centers for Disease Control and
Prevention, Wisconsin has the highest reported incidence of blastomycosis for humans, with rates in some northern counties 10 to 20 times above the national average.
In the case of a dog like Stinger, who’s traveled all over the country to compete in field trials, it’s hard to know precisely where or when he contracted the infection, especially since signs of the disease may not occur for weeks or months. Coincidentally, Kampo has a cottage in northern Wisconsin to which he often takes Stinger.
Exposure to areas that have been recently excavated has been shown to increase the risk of blasto in humans, presumably because it liberates large quantities of spores into the air, but the real risk of blastomycosis is proximity to water or moisture. Multiple studies have shown that dogs living within 400 meters of water are vastly more likely to develop blastomycosis than other dogs. Indeed, there’s some evidence to suggest that the shores of beaver ponds tend to be blasto “hotspots,” or what epidemiologists call “enzootic areas.”
