There’s no vaccine, and no way to test the ground. The best protection is to limit contact with damp, disturbed soil and to know the warning signs so you act fast.
Places to be careful
- Riverbanks, creek beds, pond edges and lake shores, especially muddy, silty, sandy or leafy edges. Swimming itself isn’t the concern; digging and sniffing at the water’s edge is.
- Shorelines and sandy areas that have recently flooded
- Muddy ground and puddles in the woods or near water
- Beaver ponds and dams, and wet wooded floodplains and swamps
- Rotting logs, stumps, leaf piles and compost, anywhere wood and leaves break down in damp soil
- Construction and excavation sites, and freshly dug ground
- Anywhere local cases have been diagnosed, especially nearby riverbanks, trails and building sites
Times to be careful
- When soil is being dug or moved, by your dog, by you or by construction crews
- Windy, dusty days. The CDC advises staying inside in windy, dusty conditions.
- After rain, fog or heavy dew. Vets note moisture may help release spores from the soil.
- Late summer and fall. Most dog cases are diagnosed then, so be extra alert to symptoms in those months.
Protecting your dog
- Keep your dog leashed near water and out of muddy banks, beaver areas and rotting wood.
- Discourage digging, especially in damp, shady or leafy spots.
- Choose drier, open trails over wet woodland and riverside paths.
- Steer clear of construction and excavation sites on walks.
- Learn the warning signs and keep a note of where your dog has been, so you can tell your vet.
Protecting yourself
- Avoid activities that stir up dirt in wooded areas or at the water’s edge, especially if your immune system is weakened.
- Wear long sleeves and pants in the woods.
- Wear an N95 mask at construction sites or when moving a lot of soil, leaves or rotting wood.
- Wash your hands after handling soil.
Can I kill it in my yard?
Not with any proven method. The Ontario Animal Health Network says “there is no way to eliminate the fungus from the soil.” There’s no public test to find it either, so you can’t confirm whether a yard has it or whether a treatment worked. We found no evidence that fungicides, bleach or lime remove it from soil, and pouring chemicals on the ground can harm pets, people and nearby streams.
What you can do is make your yard less inviting to the fungus and reduce how much spore-laden dust gets stirred up. University of Vermont Extension suggests:
- Improve drainage in and around gardens and landscaping so soil doesn’t stay soggy.
- Don’t let wet, rotting layers build up at the bottom of leaf piles and brush piles.
- Move soil and yard material when it’s dry, and not on windy days.
- Cover bare soil and stored yard material.
Common-sense extras (not proven, but low-risk): fence off the wettest, shadiest corners of the yard and any stream bank so your dog can’t dig there, and keep firewood and compost off the ground and away from where your dog plays.
Help your community
- If your dog is diagnosed, tell your vet where you think the exposure happened, and tell neighbors who walk the same areas.
- Share this site with dog owners, groomers, trainers and vet clinics, especially near rivers.
- Ask your state and local health departments to track blastomycosis. New Jersey doesn’t require reporting, so local cases go uncounted.
Blasto Awareness shares public information for awareness only. It is not veterinary or medical advice. Sources: CDC; Merck Veterinary Manual; dvm360; Ontario Animal Health Network; University of Vermont Extension; Wisconsin Department of Health Services. Full list on the Sources page.