In most cases, tuberculosis (TB) produces no symptoms and causes no immediate harm to the body. People with healthy immune systems are able to fight and disable the bacteria that can cause TB. These disabled bacteria may remain dormant in the body (latent TB) for many years, although they can be reactivated (active TB) when the immune system weakens.

Signs and symptoms of an active TB infection include:

• A cough that lasts for over three weeks
  
  
• Discolored or bloody sputum (mucus coughed up from the lungs)
  
  
• Night sweats
  
  
• Chills
  
  
• Fatigue
  
  
• Mild fever
  
  
• Loss of appetite, which may cause weight loss
  
  
• Pain in the chest while breathing or coughing

TB can spread to other parts of the body (extrapulmonary TB), in which case different symptoms may occur, including:

• Painful urination or blood in the urine – TB in kidney or bladder
  
  
• Pus draining from lymph nodes – TB in lymph nodes
  
  
• Lump in scrotum (in men) or sterility (in women) – TB in reproductive system
  
  
• Back pain or paralysis – TB in spine