Coughing excessively in public

Why is it that some people who are afflicted with a hacking cough, do nothing to silence it themselves?
All day, in the office, it's from about three cubes over. It's freaking echoing throughout the entire office.

I'm about to go buy the guy some cough drops, cough syrup, and a bottle of whiskey just to shut 'em up.

This is getting ridiculous.