Pigeon droppings have been associated with lung diseases, including Cryptococcosis, Histoplasmosis and Psittacosis, US health department said. People can get infected by breathing in the dust created when the droppings dry out. A Sir Ganga Ram Hospital study revealed that an 11-year-old boy was diagnosed with Hypersensitivity Pneumonitis after prolonged contact with pigeon feathers and droppings.