Researchers have discovered a fundamental mechanism that affects the size of the pupil, namely our breathing. The study shows that the pupil is smallest during inhalation and largest during exhalation ...

Pneumonia in both lungs is treatable, but it can be life-threatening in elderly patients like the 88-year-old pontiff.

As emergency rooms see more patients with respiratory complications, hospitals are being asked to test for possible bird flu in humans.

The risk of bird flu to the public remains low, and no poultry were sold at the Union County market that may have been infected, officials said.