Psittacosis and Bird Droppings

Psittacosis is a bacterial respiratory infection caused by Chlamydia psittaci. The CDC describes it as an illness transmitted most commonly by breathing in dust containing dried bird droppings or respiratory secretions from infected birds. While the name comes from psittacine birds (parrots, cockatiels, parakeets), wild birds including European starlings, house sparrows, and pigeons can also carry and shed the bacteria.

Quick Reference

How Psittacosis Differs from Fungal Droppings Diseases

Unlike histoplasmosis and cryptococcosis, which are caused by fungi that grow in droppings, psittacosis is a bacterial infection carried by the birds themselves. The bacteria are shed in droppings and respiratory secretions from infected birds, and they can remain viable in dried droppings for extended periods. This means psittacosis transmission can occur from droppings that are weeks or months old, not just fresh material.

The CDC’s clinical overview confirms that people can get infected from even transient exposure to infected birds or their droppings. You do not need prolonged contact. Brief exposure to concentrated dried droppings in an enclosed space, such as cleaning out a vent duct or entering an attic with heavy bird contamination, can be enough.

Transmission in Residential Settings

For homeowners dealing with birds nesting in birds in exhaust vents, attic spaces, or birds in chimney, the transmission pathway is the same as for other droppings-related diseases: dried droppings in an enclosed space connected to the home’s air circulation. Specific scenarios include:

• Turning on a contaminated bathroom fan – moves air through a duct containing dried droppings and bacterial dust
• Removing nesting material by hand – disturbs dried droppings and puts bacterial particles directly into the breathing zone
• HVAC air movement through a contaminated attic – pulls bacterial dust from the attic into the ductwork and living space
• Handling dead birds – direct contact with an infected bird’s remains without gloves and respiratory protection

Symptoms and Treatment

Psittacosis symptoms typically appear within 5 to 14 days of exposure. The illness often starts with sudden onset of fever, headache, and muscle aches, followed by a dry cough. Many cases are mild and can be mistaken for flu or a routine upper respiratory infection, which means psittacosis is likely underdiagnosed.

Severe cases can develop into pneumonia requiring hospitalization. However, psittacosis responds well to antibiotic treatment, particularly doxycycline. Most patients recover fully with appropriate therapy. The key is recognizing the exposure history – if a respiratory illness follows known contact with bird droppings or nesting material, psittacosis should be considered.

Who Is at Risk

• People who work with or around birds regularly (poultry workers, pet store employees, veterinarians)
• Homeowners who disturb accumulated bird droppings during DIY nest removal or attic work
• Construction and maintenance workers who encounter bird nests during renovation or repair projects
• Anyone with prolonged exposure to dried bird droppings in an enclosed or poorly ventilated space

Unlike cryptococcosis, psittacosis does not disproportionately affect immunocompromised individuals. It can cause illness in otherwise healthy people, particularly when the bacterial load in the inhaled dust is high.

Prevention

Prevention follows the same principles as other droppings-related diseases: do not disturb accumulated bird droppings without proper protection, have large accumulations cleaned up professionally, and address the bird infestation through professional bird control and proper bird exclusion so droppings do not continue to accumulate. Any bird damage repair to ductwork or insulation contaminated by droppings should be repaired as part of the same project to eliminate the ongoing exposure risk.