Story highlights

Website Travelmath.com sent a microbiologist to take 26 bacteria samples from five airports and four flights

Lab results found airplane tray tables to be the dirtiest of all tested surfaces

All 26 samples were negative for the presence of fecal coliforms such as E. coli

CNN  — 

There’s no better way to test your body’s immune system than by subjecting it to air travel.

With all those enclosed spaces, recirculated air and non-stop streams of peo