Signs and symptoms vary between acute, subacute, and chronic hypersensitivity pneumonitis and may include flu-like illness including fever, chills, muscle or joint pain, or headaches; rales; cough; chronic bronchitis; shortness of breath; anorexia or weight loss; fatigue; fibrosis of the lungs; or clubbing of fingers or toes. Complications of chronic disease may include irreversible lung damage, permanently reduced lung function, pulmonary hypotension, or heart failure.