Hill Top residents have been warned to avoid contact with parrots following the diagnosis of psittacosis in wild rosellas.
Three Hill Top residents have reported dead rosellas on their properties. One of these birds has been tested and found to have psittacosis.
South Western Sydney Area Health Service Public Health specialist Dr Leon Heron said psittacosis could be transmitted to humans from wild birds but it was uncommon.
"Human psittacosis usually starts with influenza-like symptoms but may develop into pneumonia and require treatment in hospital," Dr Heron said.
"Timely treatment with effective antibiotics usually results in complete recovery.
"Because psittacosis can be transmitted to humans by birds or their droppings, we advise that Hill Top residents should limit contact with parrots especially sick or dead wild rosellas, at this time," Dr Heron said.