Inhale, exhale.
Humans breathe between 17,000 to 23,000 times a day, on average. But for more than 70,000 children and young adults around the world, taking a breath can be a struggle because of a rare disease, cystic fibrosis.
A gene that normally triggers a certain protein to move chloride, found in salt, to cell surfaces, where it can attract water, malfunctions in cystic fibrosis patients, so their mucus becomes thick and sticky.
In the lungs, the thick mucus clogs airways. It also becomes a breeding ground for harmful bacteria like Pseudomonas aeruginosa, a particularly nasty pathogen that can quickly lead to inflammation and life-threatening infections.
Normally, mucus is not just a gross byproduct of a cold or viral infection; it is an important biological material that helps us fight off illness. Our bodies make a lot of mucus, maybe as much as 1.5 liters a day, which acts as a protective coating in our sinuses, lungs, intestines, stomach and throat.