Bird droppings can make a person sick, especially in areas with high populations of urban birds like pigeons, starlings, and sparrows. Bird excrement harbors various pathogens, including fungi and bacteria, that are transmissible to humans (zoonotic disease transmission). The risk is generally low for brief, casual exposure. However, risk increases significantly when large, dried accumulations are disturbed, releasing particles into the air. Understanding these airborne and contact risks is important for mitigating potential exposure.
Primary Illnesses Transmitted by Bird Droppings
Illnesses associated with bird droppings fall into two main categories: fungal and bacterial infections. Fungal diseases often originate in soil enriched by large, long-term accumulations of bird waste. Histoplasmosis is a respiratory infection caused by the fungus Histoplasma capsulatum, which thrives in soil contaminated by bird or bat droppings. Cryptococcosis, caused by Cryptococcus neoformans, is a fungal infection linked to soil contaminated by pigeon and starling droppings, often beginning as a pulmonary disease.
Bacterial infections include Psittacosis, sometimes called Parrot Fever. This illness is caused by the bacterium Chlamydia psittaci and is shed in the feces and respiratory secretions of infected birds. Gastrointestinal illnesses like Salmonellosis and E. coli contamination are also relevant. These bacteria are acquired if droppings contaminate food or water sources, or through direct contact.
Routes of Exposure and Transmission
The primary mechanism for contracting airborne illnesses from bird droppings is the inhalation of aerosolized particles. When dried bird waste, especially large accumulations under roosts, is disturbed, microscopic fungal spores or bacterial cells become suspended in the air. Activities like cleaning, demolition, or sweeping areas with old droppings create this fine dust, which is easily breathed into the lungs. This is the main route of transmission for Histoplasmosis, Cryptococcosis, and Psittacosis.
Another route involves direct contact and subsequent ingestion or contact with mucous membranes. If droppings contaminate surfaces, a person can pick up bacteria like Salmonella on their hands and transfer the pathogen to their mouth, nose, or eyes. This risk is heightened when droppings land near open food and water supplies, leading to ingestion of the bacteria. Diseases caused by ingestion typically result in gastrointestinal symptoms.
Recognizing Symptoms and When to Seek Medical Attention
Many people exposed to pathogens from bird droppings never develop symptoms or experience only a mild, self-limiting illness. When symptoms appear, they often mimic the flu, including fever, chills, headache, muscle aches, and a dry cough. Respiratory symptoms like shortness of breath or chest pain are associated with Histoplasmosis and Psittacosis. Gastrointestinal issues such as diarrhea, nausea, and vomiting suggest a bacterial infection like Salmonellosis.
If you develop flu-like symptoms within a few weeks of known exposure, call a healthcare provider. Prompt medical consultation is important if symptoms are severe, worsen, or persist beyond a few days. Individuals with weakened immune systems, infants, and the elderly are at a higher risk of developing severe, life-threatening complications, and should seek immediate medical attention following potential exposure.
Safe Handling and Cleanup Practices
The most effective measure for safe cleanup is preventing dry droppings from becoming airborne dust. Never use dry-sweeping, shoveling, or a regular vacuum cleaner on large accumulations, as this will aerosolize pathogens. Instead, the droppings should be thoroughly wetted down with a low-velocity mist of water or a mild disinfectant solution before removal. This moisture binds the spores and bacteria to the waste material, significantly reducing the inhalation risk.
Proper personal protective equipment (PPE) must be worn during cleanup to mitigate exposure risk. This equipment includes:
- Heavy rubber or disposable gloves.
- Disposable coveralls.
- A properly fitted N95 respirator mask or a half-face respirator with a P3 filter.
The contaminated material should be double-bagged in durable plastic bags before disposal. All reusable tools should be disinfected with a 10% bleach solution, and hands must be washed thoroughly after removing all PPE. For very large or extensive contamination, contacting a professional remediation service is the safest course of action.