Once you hop on board, just about every surface you come into contact with harbors bacteria that can make you sick (including traces of fecal matter—gross!), so make the phrases “don’t touch” and “wash hands” your mantra. If you’re not able to swab down surfaces on buses, subways and taxis before you sit, at least scrub up after any trip to reduce the chance of contracting an illness.

READ MORE: Gross or Dangerous? The Travel Edition