Raccoons are adaptable species thriving in urban and suburban environments due to readily available food and shelter. This close proximity increases the potential for transmitting zoonotic diseases, which are illnesses shared between animals and humans. Understanding the health risks raccoons pose is important, as several pathogens carried by these mammals can lead to serious conditions in people. These risks include parasitic infections spread through contaminated waste and viral or bacterial diseases transmitted through direct contact or environmental contamination.
Baylisascaris Procyonis: The Unique Parasitic Threat
The raccoon roundworm, Baylisascaris procyonis, is a severe parasitic danger unique to this animal. The life cycle begins when adult worms in the raccoon’s small intestine shed millions of microscopic eggs in the host’s feces. Raccoons tend to defecate repeatedly in communal sites known as latrines, often found in attics, woodpiles, decks, or at the base of trees.
The eggs are not immediately infectious but require two to four weeks in the environment to mature into an infective stage. These larvated eggs are resilient to disinfectants and can remain viable in soil and debris for several years. Humans, especially young children, become infected when they accidentally ingest these eggs through contact with contaminated soil, water, or surfaces.
After ingestion, the eggs hatch, and the larvae migrate aggressively through the body’s tissues, a condition called Larva Migrans. This migration can result in Visceral Larva Migrans (VLM) if the larvae travel through organs, or Ocular Larva Migrans (OLM) if they enter the eye, potentially causing vision loss. The most severe consequence is Neural Larva Migrans (NLM), where larvae invade the brain and spinal cord, leading to severe neurological damage, which is often devastating or fatal.
Viral and Bacterial Pathogens Transmitted by Raccoons
Rabies
Rabies is a viral disease for which raccoons are a major reservoir in many regions. The virus infects the central nervous system and is fatal in humans once symptoms appear. Transmission occurs through contact with the saliva of an infected animal, typically via a bite or a scratch that breaks the skin.
Any raccoon exhibiting unusual behavior, such as staggering, uncoordinated movements, or lack of fear toward humans, should be treated as potentially rabid. The virus has a variable incubation period, requiring immediate medical intervention following exposure. Rapid administration of Post-Exposure Prophylaxis (PEP) is the only effective way to prevent the disease’s onset, so exposure must be reported quickly to health officials.
Leptospirosis
The bacterium Leptospira causes Leptospirosis, which raccoons can carry without showing symptoms. This pathogen is shed in the raccoon’s urine and can contaminate standing water, soil, and surfaces. Humans contract the disease when the bacteria enter the body through breaks in the skin or mucous membranes, such as the eyes, nose, or mouth.
Initial symptoms often resemble the flu, including fever, headache, muscle aches, and vomiting. The infection can progress to a serious stage, sometimes causing severe complications like kidney damage, liver failure, or meningitis. Because the bacteria thrives in moist environments, areas with pooled water or wet soil frequented by raccoons pose a heightened risk.
Protecting Yourself and Your Property
Prevention and Avoidance
Reducing the attractiveness of your property is the most effective defense against raccoon-transmitted diseases. Secure all garbage cans with tight-fitting, animal-proof lids or use bungee cords to prevent access to food waste. All outdoor pet food and water bowls should be removed, especially overnight, as these are strong attractants for nocturnal foraging.
Inspect your home for potential entry points where raccoons may seek shelter, such as chimneys, attics, and underneath decks. Installing chimney caps and trimming tree branches that offer easy access to the roof can prevent raccoons from establishing dens. Motion-activated lights or sprinklers can also serve as non-lethal deterrents to discourage raccoons from lingering.
Safe Cleanup Procedures
Cleaning areas contaminated by raccoon feces requires specific precautions to prevent the ingestion of roundworm eggs. Always wear disposable gloves, rubber boots or shoe covers, and an N95-rated particle mask, particularly when working in enclosed spaces like an attic. Contaminated material should be carefully removed using a shovel or an inverted plastic bag, avoiding sweeping or vacuuming, which can aerosolize the eggs.
Feces and soiled materials must be double-bagged in heavy-duty plastic bags and sealed before disposal in a landfill. Since Baylisascaris eggs are resistant to most chemical disinfectants, contaminated surfaces like decks or concrete should be treated with boiling water or a propane torch to kill the eggs instantly with heat. Afterward, all protective gear should be disposed of, and clothing should be washed separately in hot water and detergent.
Emergency Response
If a bite or scratch from a raccoon occurs, immediate action is necessary to minimize the risk of rabies and bacterial infection. The wound should be thoroughly washed with soap and running water for 15 minutes to cleanse the site of potential viral particles. Following this first aid, medical attention must be sought without delay.
Contacting local animal control or public health officials is necessary to report the exposure and determine the next steps regarding the animal. Medical professionals will assess the need for Post-Exposure Prophylaxis (PEP), which includes a series of vaccinations and, in some cases, the administration of Rabies Immune Globulin. PEP is effective in preventing rabies when administered in a timely manner.