What specific pathogens have been ruled out in teh investigation of this novel squirrel disease?

Mysterious illness Causes Bizarre Oozing Squirrels to Proliferate in U.S. Backyards

What’s Happening to the Squirrels?

Across the United States, homeowners are reporting a disturbing trend: squirrels exhibiting lesions, oozing fluids, and, in certain specific cases, a generally unwell appearance. This isn’t a localized issue; reports are surfacing from states including Florida, Pennsylvania, and increasingly, across the Midwest. The primary symptom causing concern is the presence of open sores, often around the face, paws, and tail, accompanied by a discharge. While initial speculation ranged from mange to injuries, veterinary pathologists are now pointing towards a novel, and currently unidentified, illness.

This emerging squirrel disease is causing important anxiety among wildlife enthusiasts and pet owners alike. The condition is impacting both Eastern Gray Squirrels (Sciurus carolinensis) and Fox Squirrels (Sciurus niger), the most common species in many areas.

Identifying the Symptoms: What to Look For

Early detection is crucial, even though a definitive diagnosis remains elusive. Here’s a breakdown of the key symptoms to watch for in your local squirrel population:

Visible Lesions: Open sores, scabs, or raw patches of skin. These are often the first sign.

Oozing or Discharge: Fluid leaking from the lesions. The discharge can vary in color and consistency.

Swelling: Inflammation around the affected areas.

Neurological Signs: In some cases, squirrels have exhibited unusual behavior, including appearing disoriented or having difficulty moving. (Though this is less common).

Hair Loss: Patches of missing fur around the lesions.

Lethargy: A noticeable decrease in activity levels. Squirrels may appear sluggish or unresponsive.

Its significant to differentiate these symptoms from common squirrel ailments like squirrel mange, which typically presents with intense itching and hair loss, but less prominent open wounds.

The Current Investigation: What Do Experts Say?

Veterinary diagnostic laboratories, including those at universities like Cornell and Pennsylvania State University, are actively investigating the cause. Initial tests have ruled out common pathogens like rabies, distemper, and tularemia.

Here’s what we know so far:

1. Not a Known Virus: Extensive testing hasn’t identified a known viral agent responsible for the illness.
2. Bacterial involvement Possible: Some labs are exploring the possibility of a bacterial infection, potentially secondary to another underlying cause.
3. Possible Environmental factor: Researchers are investigating potential environmental toxins or pollutants that could be contributing to the outbreak.
4. No Evidence of Human Transmission: As of August 17, 2025, there have been no confirmed cases of human infection related to this squirrel illness. Though, experts advise caution and avoiding direct contact with sick animals.

The Pennsylvania Game Commission has urged residents to report sightings of sick or dead squirrels to help track the spread of the disease. Similar initiatives are underway in other affected states.

Is it Contagious? Transmission Concerns

The method of transmission remains unclear. While it’s not definitively known if the illness is directly contagious from squirrel to squirrel, the increasing number of cases suggests some form of spread. Potential transmission routes being investigated include:

Direct Contact: Through skin-to-skin contact with infected squirrels.

Shared Food Sources: Contamination of nuts,seeds,or other food sources.

Vectors: The possibility of ticks, fleas, or other insects acting as carriers.

Environmental contamination: Exposure to contaminated soil or water.

Protecting Your Pets and Family

While the risk to humans is currently considered low, it’s prudent to take precautions:

Avoid Contact: Do not approach, touch, or attempt to handle sick or dead squirrels.

Pet Safety: Keep pets away from sick or deceased squirrels. If your pet comes into contact with a squirrel, monitor them for any signs of illness and consult your veterinarian.

Bird Feeders & Squirrel Feeders: consider temporarily removing bird feeders and squirrel feeders to reduce congregation and potential spread. Clean feeders thoroughly if you continue to use them.

Garden Hygiene: Wear gloves when gardening and wash your hands thoroughly afterward.

Report sightings: Report any sick or dead squirrels to your local wildlife authorities.

Florida: Initial reports in early 2025 focused on the southeastern portion of the state, with a high concentration of cases reported in Palm Beach County.

Pennsylvania: The Pennsylvania Game Commission has received hundreds of reports of sick squirrels, especially in the eastern and central parts of the state.

Ohio: Increasing reports in the last month suggest the illness is spreading westward.

* Illinois: Isolated cases have been confirmed, prompting increased monitoring by the Illinois Department of Natural resources.

these regional outbreaks highlight the need for a