Birds carry a number of zoonotic diseases, or diseases that can transfer from the bird to humans. Transmission commonly occurs when the human either inhales or ingests infected dropping particles. People with poorly functioning immune systems, the elderly and young children must practice extreme caution around bird droppings. Maintaining a clean, sterile cage daily is the best preventative method that a pet owner can employ.
Salmonella bacteria live and thrive in the digestive tracts of many pet birds. The bacteria is easily shed in the bird's fecal matter. It is also less commonly shed in the bird's nasal secretions, ocular secretions and even the feather dust. Humans can easily inhale the bacteria when cleaning the bird's cage, changing its water, feeding it or handling it. In humans, the bacteria will cause a high fever, vomiting, cramping and diarrhea. Salmonella is considered to be a serious infection that is often life-threatening. A few humans who contract salmonella will become carriers of the disease without ever exhibiting any symptoms, according to the Centers for Disease Control.
Chlamydophila psittaci bacterium is known to infect 465 avian species. From the years of 1988 through 2003 there were 935 human cases of the disease contracted from birds, according to the Centers for Disease Control. The disease is spread from the bird to humans by bodily fluids such as eye and nose discharge or droppings. Humans inhale or ingest the bacteria. Tetracycline is used to treat the infection in humans. The symptoms of the disease start out as flu-like in appearance but can quickly progress to an acute respiratory condition that resembles pneumonia.
Mycobacterium avium causes avian tuberculosis. The disease is spread from the fecal matter of infected birds. Humans inhale or ingest particles that contain the disease while cleaning or handling the birds or their cages. The condition is normally treatable with antibiotics but can be life-threatening in the very young, old or those with suppressed immune systems. One variation of the disease, M. avium, is resistant to antibiotics and very difficult to treat, according to the University of Florida. When a human is infected with the antibiotic-resistant strain, the only way to stop the infection is removal of the infected lymph nodes and tissue through surgery. The disease manifests with flu-like symptoms and is followed by a severe respiratory condition.
Histoplasmosis capsulatum occurs when soil becomes infected with bird droppings. In tropical and sub-tropical regions, many pet bird owners house their parrots or other bird species outside in aviaries during nice weather. The disease only occurs when the birds' droppings remain in the soil and the human or animal inhales the particles. The disease appears with flu-like symptoms which quickly become acutely pulmonary. The infected individual often exhibits symptoms that are similar to tuberculosis. Left untreated, the disease can often prove fatal to infected humans. Amphotericin B is the treatment of choice.