My friends 7 week old nearly died 3 weeks ago from rhinovirus. His O2 when they got to childrens was 82%. He was on something like 22 liters per minute of oxygen by high flow nasal cannula to keep his oxygen level up. Spent a week in the hospital half in the PICU. His spit was basically carbonated they pumped him so full of oxygen. Super scary, and both parents are healthcare workers, so it was recognized quickly that he was sick.