Percentages range, but studies all over the world support the fact that yes indeed air moves from your basement up to the rest of the home. 40% or more of the air you breathe on a regular basis comes from the basement.
That link is another one of my articles, recently published, on stack effect, and air quality in the home. Your basement's current state effects the rest of your home more than you know. And if you're looking for a good investment and project to do during these times to not only better the air in your home, but protect your basement, family, and foundation then this is a good article to read.
If you want to browse more in my blog here:
Air quality, affected by basement
Stoping water coming through your Foundation Walls