While some zoonoses birds carry can cause mild illness in humans, others pose serious public health concerns.
Infected birds shed these viruses through their feces, saliva, and mucus.
In humans, bird flu causes a respiratory infection ranging from mild to severe and life-threatening.

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Psittacosis
Also known as parrot fever, psittacosis is an infection caused byChlamydia psittaci.
Salmonellosis
Salmonellosisis an infection caused bySalmonellabacteria.
Though rare, humans can contract salmonellosis from direct contact with infected birds or bird droppings.
Cryptococcosis
Cryptococcosisis a fungal infection caused byCryptococcus neoformansandCryptococcus gattii.
While the disease primarily affects people with compromised immune systems, otherwise healthy people can also contract the disease.
In humans, cryptococcosis initiallyaffects the lungs, causing mild chest pain and coughing.
Histoplasmosis
Histoplasmosisis a fungal infection caused byHistoplasma capsulatum.
This fungus thrives in soil where there are large amounts of bird droppings.
Human histoplasmosis infections develop after inhaling fungal spores in dried bird droppings.
The spores become airborne when the infected soil is disturbed, such as during gardening or yard work.
Cryptosporidiosis
Cryptosporidiosisis a parasitic infection resulting from ingestingCryptosporidiumoocysts, which are microscopic parasites.
These can spread through direct contact with contaminated feathers or inhalation of airborne particles on the feathers.
Use protective gloves and wash hands thoroughly after handling feathers to help reduce the risk of infection.
Disease transmission from bird droppings typically occurs through direct contact, ingestion, or inhalation.
Direct contact involves touching contaminated surfaces or objects and touching your mouth, nose, or eyes.
Some pathogens can input your body by inhaling airborne particles from dried bird droppings.
In healthy people, the body’s immune system can effectively fight off mild cases of some zoonotic diseases.
Treatment for diseases contracted from sick birds varies by the bang out and severity of the infection.
Mild infections may resolve with time and self-care measures, such as hydration and rest.
Some infections require antibiotics, antiviral, antifungal, or antiparasitic medications.
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