Probably the most likely path to infection is from hand to mouth/nose/eye contact. Most influenza/rhino viruses aren't strong enough to penetrate the epidermis directly, but will contaminate the hands fairly easily, and then we wipe our face or touch food or drink or some such that then contacts our mouth etc and then we get infected. Wearing a mask is actually beneficial as a barrier against self infection by keeping our hands out of our mouths, off our noses, etc. You are more prone to decontaminate first before doffing the mask this way, and greatly reduce the risk of infection. Wearing a mask and eye protection would be quite desirable in this respect. Of course airborn vectors are always a factor to consider (the theater scene from the movie "Outbreak" exemplifies such a problem), and in this way a mask and eye protection are a definite advantage as well.

Personally, if we had a really virulent disease running rampant, I would opt for an enviro suit (level B at the least), kinda like what the stormtroopers wear, only better sealed and more air conditioned. If we get an "Andromeda Strain" variant, I'll just go to ground and close the lid.
The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)