Difficulty breathing can occur when a child's lungs or heart are not working well.

Mild trouble breathing means:

• The child is breathing a little faster than usual.
• The child seems a little out of breath but can still eat or talk.

Moderate trouble breathing means:

• The child is breathing a lot faster than usual.
• The child has to take breaks from eating or talking to breathe.
• The nostrils flare or the belly moves in and out at times when the child breathes.

Severe trouble breathing means:

• The child cannot eat or talk because he or she is breathing so hard.
• The child's nostrils are flaring and the belly is moving in and out with every breath.
• The child seems to be tiring out.
• The child seems very sleepy or confused.