They don't take precautions. Since I started making my own cleaning products, hand sanitizers, etc...my 2 kids and I have NEVER been sick for 4 years and none of us EVER had a flu shot. Just plain ol' vinegar, hydrogen peroxide, or rubbing alcohol is better than any commercial cleaner.
You need to clean all surfaces daily, wash hands after bathroom use or being at the store or school, handling raw meat, etc. I clean all door knobs and light switches with alcohol every other day, etc.
It's all about being clean and aware of the surfaces germs can exist...plain and simple.