If parrots are given a healthy diet and kept in a clean cage, they are very unlikely to be a source of infection for their human neighbors. Always wash your hands with soap and water after handling the birds or anything in their cage or aviary, or after changing the food bowls.
Another good policy is to wear rubber gloves when you clean out the cage. You should also wear a mask to avoid breathing in dust if cleaning out a birdhouse or aviary. It's also a good idea to avoid any mouth contact with the bird - don't hold food in your mouth for the parrot to take, and avoid beak-to-mouth "kisses".
Sick as a Parrot? This African Grey is taking a health check
Sick as a Parrot
Most health issues involved with parrot keeping are to do with the birds' health, rather than the health of their owners. There are many avian diseases that can make a parrot’s life a misery - as hinted at in the phrase ‘sick as a parrot’. However, the saying itself does indeed refer to humans falling sick due to contact with parrots.
"Sick as a parrot" was first coined in the mid-1920s, when there was a serious outbreak of Parrot Disease. Almost 1,000 people were infected, and the disease was studied and identified for the first time. Infection was found to be caused by inhalation of infected ‘dander’ - dust from feathers and dried parrot droppings.