Possible routes of transmission can be:
Contact infection:
Here the viruses/bacteria are transmitted from person to person through touch.
Droplet infection:
Viruses and bacteria are transmitted through the air in small droplets. With this type of transmission, a person becomes infected when these droplets are inhaled or when they get onto the mucous membranes of the eyes and multiply there.
Contamination infection:
Here the viruses/bacteria are transmitted by touching contaminated (dirty) objects.
Fecal-oral infection:
Pathogens that are excreted in the stool are absorbed into the mouth through direct or indirect contact via the hands.