Keyboard and Mouse Combo

One question I get alot is "should I replace my keyboard and mouse; it is old but works?"  The answer to that is "yes" and they should be once a year or at every two years.  

Best practice is replaced keyboard and mouse yearly or every two years.  They are very dirty, and germs and bacteria are indeed growing on those things.

These keyboards and mice comb are inexpensive and should be considered replace annually.  My go to brand is Logitech.