Have you ever wondered why Japanese wear face masks?
If you visit Tokyo or in some other Asian countries, have you seen that people are wearing face masks. What would be your guess? They are afraid of getting sick?
The truth is they are already sick and they are wearing those masks to avoid germs from spreading. In Japan it is expected that you wear a mask if you are sick, and it is really unacceptable to refrain from it.
So during your visit to Japan, if you get sick with coughing and sneezing, remember to wear a mask when you go outside. Nowadays in Japan, there are face masks with antimicrobials and considered to be killing bugs on the surface of the mask.