Salmonellosis and Bird Droppings

Salmonellosis is a bacterial infection caused by Salmonella species found in the droppings of many bird species. Unlike the fungal diseases associated with bird droppings (histoplasmosis and cryptococcosis), salmonellosis is transmitted through the fecal-oral route rather than inhalation. The CDC has documented cases of human salmonella infections linked directly to contact with wild birds and surfaces contaminated with bird droppings.

Quick Reference

The Wild Bird Connection

A peer-reviewed study published in CDC’s Emerging Infectious Diseases journal confirmed the link between Salmonella Typhimurium in wild songbirds and a human illness outbreak in the United States during 2020-2021. This was the first confirmed epidemiological link between Salmonella in wild birds and human illness, establishing that wild birds are not just carriers but active sources of human infection.

The Cornell Wildlife Health Lab confirms fecal-oral transmission and notes that people and domestic animals have become infected through contact with infected songbirds and surfaces they have contaminated.

Transmission in Residential Settings

Salmonellosis from bird droppings follows a different pathway than the respiratory diseases. It is not transmitted by breathing contaminated dust. Instead, it requires contact with droppings or droppings-contaminated surfaces followed by hand-to-mouth transfer. In a home setting, the highest-risk scenarios are:

• Droppings near food preparation areas – birds nesting in kitchen exhaust vents or roosting on exterior windowsills near kitchen windows create a direct contamination pathway
• Children contacting droppings – accumulation on porches, play areas, outdoor furniture, or walkways where children touch surfaces and then touch their faces
• Pet food and water bowls – outdoor bowls contaminated by droppings from roosting or nesting birds
• Handling contaminated material without gloves – removing nesting debris or cleaning droppings without hand protection, then eating or touching the face
• Gardening in contaminated soil – droppings from roost sites wash into soil and garden beds, contaminating surfaces that gardeners contact with bare hands

Comparison with Other Droppings-Related Diseases

This distinction matters for great-tailed grackles roosts on commercial properties. While histoplasmosis and psittacosis primarily concern enclosed spaces, salmonella contamination from grackle droppings is a concern in open areas like restaurant patios, sidewalks, and parking lots where people contact contaminated surfaces.

Symptoms and Treatment

Salmonellosis symptoms typically appear within 6 to 72 hours of exposure and include diarrhea, abdominal cramping, fever, nausea, and vomiting. Most cases resolve within 4 to 7 days without antibiotic treatment. However, severe cases can occur in young children, older adults, and immunocompromised individuals, sometimes requiring hospitalization for dehydration or bloodstream infection.

Prevention

• Wash hands thoroughly after contact with outdoor surfaces in areas with visible bird droppings
• Do not handle bird droppings, nesting material, or dead birds without gloves
• Keep outdoor pet food and water bowls covered or away from bird roosting and nesting areas
• Clean droppings from food preparation surfaces, outdoor dining areas, and children’s play areas promptly
• Address the source through professional bird control and bird exclusion to prevent ongoing contamination