Possum droppings carry real health risks for humans and animals. The feces can contain bacteria, parasites, and fungal spores that spread through direct contact, contaminated food or water, and even inhalation of dried material. The level of danger depends on what pathogens the possum is carrying, how you come into contact with the droppings, and whether you have pets or horses that might encounter them.
What Possum Droppings Look Like
Possum scat is small, cylindrical, and slightly tapered at the ends, typically dark brown or black. Brushtail possum droppings are roughly 14 millimeters long (about twice the size of rat droppings), while ringtail possum pellets fall somewhere between rat and brushtail size. The texture and contents shift with the animal’s diet of leaves, fruit, and flowers.
You’ll most often find possum droppings on tree branches, in roof spaces, or scattered on the ground beneath trees. In urban areas, decks, patios, and garden beds near fruit trees are common spots. If you’re finding small dark pellets in your attic or along your roofline, possums are a likely culprit.
Diseases in Possum Feces
The primary bacterial concern is leptospirosis, a serious infection that can cause hemorrhagic jaundice in humans. Possums are important wildlife reservoirs for the bacteria, which they shed in both urine and feces. People typically pick up the infection by eating unwashed produce, handling windfall fruit, or touching contaminated surfaces and then putting their hands near their mouth.
Possum droppings can also harbor Salmonella and parasites like Coccidia and Giardia. These organisms cause gastrointestinal illness ranging from mild diarrhea to severe dehydration, depending on the pathogen and the person’s immune health. Children, elderly people, and anyone with a weakened immune system face higher risk from exposure.
Buruli Ulcer Risk in Australia
In southeastern Australia, ringtail and brushtail possums carry Mycobacterium ulcerans, the bacterium responsible for Buruli ulcer. This is a painful skin infection that destroys tissue and can require months of treatment. CDC research found that possum feces testing positive for the bacterium at residential properties correlated with a higher likelihood of Buruli ulcer among residents. Positive feces appeared up to 39 months before human cases emerged in the same area, making possum scat an early warning sign.
Humans may acquire the infection through mosquito bites, direct skin trauma, or contact with contaminated soil or surfaces, particularly on exposed arms and legs.
Breathing in Dried Droppings
Dried possum feces pose an inhalation risk. As droppings dry out and break apart, fungal spores can become airborne. Breathing in this dust allows spores to enter your lungs and potentially your cardiovascular system. This is especially concerning when cleaning enclosed spaces like attics, crawl spaces, or sheds where droppings have accumulated over time. Never sweep or vacuum dried droppings without protection, since that launches particles into the air.
Risks to Dogs, Cats, and Horses
Dogs are the most likely pets to eat possum droppings they find in the yard. This can expose them to Coccidia and Giardia, two single-cell parasites that standard dewormers don’t treat. Coccidia can cause loss of appetite, abdominal pain, bloody diarrhea, and dehydration. Giardia often produces persistent or intermittent diarrhea, greasy stools, gas, and weight loss, though some infected animals show no symptoms at all. Giardia is particularly tricky because several stool samples may need to be tested before it’s detected. Cats face similar risks if they encounter contaminated feces, soil, or water.
For horse owners, possum droppings present a specific and serious threat. The Virginia opossum (the only marsupial native to North America) is the definitive host for the parasite Sarcocystis neurona, which causes Equine Protozoal Myeloencephalitis (EPM). Opossums shed infective sporocysts in their feces, and horses become infected by eating contaminated feed or drinking contaminated water. An estimated 50 to 90 percent of horses in the U.S. have been exposed to the organism. In fewer than 1 percent of cases, the parasite migrates from the gut into the bloodstream, crosses into the brain, and attacks the central nervous system. That small percentage still represents a devastating outcome, so keeping opossum feces away from feed and water sources is essential.
How Long Droppings Stay Infectious
Fecal pathogens don’t die when the droppings dry out. Common bacteria like Salmonella and E. coli can survive in moist conditions for up to three months. Once deposited in soil, these organisms generally persist for at least a month, and in shaded or protected areas where they avoid UV radiation and drying, some pathogens remain viable for several months or even years. Parasite eggs and cysts tend to be even hardier than bacteria in outdoor environments. Old droppings are not safe droppings.
How to Clean Up Possum Droppings Safely
For a small amount of droppings on a deck or patio, wear rubber or plastic gloves and avoid touching your face. Spray the droppings with a bleach solution (1.5 cups of household bleach per gallon of water, or a 1:9 bleach-to-water ratio) and let them soak for at least five minutes before wiping up with paper towels. Dispose of everything in a sealed plastic bag.
For heavier accumulations, particularly in enclosed spaces like attics or crawl spaces, you need more protection:
- Gloves: Rubber, latex, or vinyl
- Eye protection: Sealed goggles, not open safety glasses
- Respiratory protection: A half-mask respirator with a HEPA filter, not a basic dust mask
- Clothing: Disposable coveralls or long sleeves, plus rubber boots or disposable shoe covers
Wet the droppings thoroughly with bleach solution before disturbing them. This keeps spores and particles from becoming airborne. Never dry-sweep or vacuum possum feces. After cleanup, wash your hands and any exposed skin with soap and warm water, and launder your clothes separately in hot water.