Opossums, commonly known as possums, are widespread nocturnal marsupials found across diverse environments, including urban and suburban areas. These adaptable animals often scavenge for food and shelter, leading to increased interaction with humans and pets. Like all wildlife, opossums can harbor various diseases and parasites. However, the risk they pose to human health is generally low.
Diseases Affecting Possums
Opossums can be affected by a range of internal and external parasites that impact their overall health. Common external parasites include fleas, ticks, mites, and lice. These ectoparasites can cause skin irritation and discomfort for the opossum.
Internal parasites are also prevalent in opossums, particularly gastrointestinal worms. These worms’ eggs are shed in their feces. Examples include roundworms such as Ancylostoma caninum, which can infest their digestive systems. Protozoan parasites like Coccidia and Toxoplasma gondii are also found in opossums.
Beyond parasites, opossums can contract bacterial infections. Abscesses, often resulting from injuries, are common bacterial issues observed in opossums.
Diseases Transmissible to Humans and Pets
While opossums are generally not aggressive, they can carry diseases transmissible to humans and pets, primarily through indirect contact or parasites they host. Leptospirosis is a bacterial infection that opossums can carry and transmit. This disease spreads through contact with the urine of infected animals or contaminated water and soil, potentially causing flu-like symptoms, and in severe cases, liver or kidney damage in humans and pets.
Salmonellosis is another bacterial infection associated with opossums. Opossums can carry Salmonella bacteria, which are shed in their feces. Humans or pets can become infected by coming into contact with contaminated droppings or surfaces. Symptoms typically include diarrhea, abdominal cramps, and fever, with young children and the elderly being more susceptible to severe outcomes.
Opossums can also host ticks and fleas, which serve as vectors for various diseases. Tick-borne diseases such as Lyme disease, Rocky Mountain spotted fever, and ehrlichiosis can be transmitted if an infected tick carried by an opossum bites a human or pet. While opossums are often cited for their role in consuming ticks, they can still carry infected ticks that pose a risk. Flea-borne typhus, caused by Rickettsia typhi, is another concern, as fleas feeding on infected opossums can transmit the bacteria to humans through bites or contaminated flea feces.
Transmission often occurs through contact with an infected animal’s bodily fluids, such as bites or scratches, or indirectly via contaminated environments like feces and urine. Pets can also acquire parasites like fleas and ticks from opossums if not on preventative medications. Therefore, minimizing direct interaction with opossums and maintaining good hygiene practices, especially in areas they frequent, can help reduce potential risks.
Understanding Low-Risk Diseases
Despite common fears, opossums are highly resistant to rabies, making transmission of the virus to humans or pets extremely rare. This resistance is primarily due to their naturally lower body temperature, which typically ranges from 94-97°F (34.4-36.1°C). The rabies virus struggles to survive and replicate effectively in cooler temperatures, hindering its ability to incubate and spread within the opossum’s system.
Opossums are also rarely associated with other diseases that are often attributed to wildlife. For example, while they can be hosts for ticks, their role in the transmission cycle of Lyme disease to humans is often overstated, and some studies even suggest they are resistant to developing Lyme disease themselves. Similarly, conditions like tularemia, while potentially carried by opossums, are generally rare in human cases. This highlights that while opossums are wild animals and can harbor various pathogens, the overall risk of disease transmission to humans and domestic animals is often lower than commonly perceived.