The Virginia Opossum is a common nocturnal visitor across much of North America, yet it remains one of the continent’s most misunderstood mammals. Often perceived as a pest or a source of danger, this animal frequently triggers concerns about physical safety and disease transmission. This article clarifies the safety profile of the opossum, examining its natural behaviors and the health risks it poses for safe coexistence.
Understanding the North American Possum
The Virginia Opossum is the only marsupial species native to North America. These solitary animals are primarily active between dusk and dawn, relying on their keen senses to navigate the environment while searching for food. They possess a long, hairless, prehensile tail and opposable thumbs on their hind feet, which aid them in climbing and grasping objects.
When severely threatened, the opossum exhibits a defense mechanism called thanatosis, or “playing possum.” This physiological response causes the animal to fall into a catatonic state, appearing dead with a limp body, open mouth, and glazed eyes. This reaction is an automatic response to extreme fear, lasting from a few minutes to several hours, and is intended to deter predators who prefer live prey.
Assessing Physical Danger and Aggression
Opossums are not naturally aggressive toward humans or pets and will almost always choose flight over confrontation. Their primary defensive actions are bluff displays intended to intimidate an aggressor into retreating. These bluffs often involve a loud hiss or growl, drooling, and baring their impressive set of fifty teeth.
A bite or scratch from an opossum is extremely rare and typically only occurs if the animal is cornered, handled, or severely provoked. If a pet attacks an opossum, the marsupial will attempt to flee or initiate its playing possum defense before resorting to fighting. The risk of serious injury to a domestic animal is significantly lower than the risk posed by more territorial wildlife like raccoons.
Disease Concerns and Transmission Risk
The opossum’s physiology provides it with a notable resistance to rabies. The average body temperature of the opossum is approximately 94–97 degrees Fahrenheit, which is several degrees lower than most other mammals. This cooler internal temperature makes it difficult for the rabies virus to replicate effectively, resulting in a very low incidence of the disease in wild opossum populations.
While the rabies risk is minimal, opossums can carry other pathogens. They can transmit bacteria like Leptospira through their urine, which can contaminate water or soil and cause leptospirosis in humans and pets. They may also carry organisms responsible for tuberculosis and tularemia.
A specific concern is the parasite responsible for Equine Protozoal Myeloencephalitis (EPM), a serious neurological disease in horses. The opossum acts as the definitive host for the protozoan Sarcocystis neurona, which is passed through its feces. Horses can contract EPM by consuming feed or water contaminated with opossum droppings, making the animal a risk on properties with horses.
Ecological Contributions and Benefits
Despite their presence in suburban areas, opossums provide several valuable ecological services. They act as effective scavengers, consuming carrion, fallen fruit, and household waste, which helps to clean the environment. Their broad, omnivorous diet also includes many common garden pests.
Opossums consume slugs, snails, and insects, helping to control these populations. They are also credited with destroying a large number of ticks through their fastidious grooming habits. A single opossum may kill thousands of ticks in a season by eating the parasites that attach to its fur, although the total impact on tick-borne disease transmission remains a subject of ongoing scientific study.
Guidelines for Safe Coexistence
The most effective way to manage interactions with opossums is to remove the factors that attract them to residential spaces. Because they are opportunistic foragers, securing all outdoor food sources is the primary deterrent. This includes keeping garbage cans tightly sealed with locking lids or bungee cords and bringing pet food bowls indoors overnight.
If an opossum is encountered on your property, the safest course of action is to leave it alone. Do not attempt to approach, touch, or move the animal, even if it appears injured or playing possum. If an opossum seems sick or is behaving erratically, contact a local animal control agency or wildlife rehabilitator for assistance. To prevent them from seeking shelter, eliminate access points under decks, porches, and sheds, and trim back tree branches that offer easy access to the roof.