Clues in the history include Recurring atypical pneumonias Symptom onset after moving to a new job or home A hot tub, a sauna, a swimming pool, or other sources of standing water or water damage in the home or regular exposure to them elsewhere Having birds as pets Exacerbation and relief of symptoms in and away from specific settings Examination often is not useful in making the diagnosis, although abnormal lung sounds and clubbing may be present.