Infectious diseases can spread through the air
Sneezes and coughs spread germs. Small particles of disease-causing microbes can float in the air for a long time, sometimes traveling on air currents. Breathing in airborne viruses, bacteria or other germ can cause a new infection. Larger droplets of disease-causing germs don't travel as far before landing on a surface. If someone touches the surface, the germs transfer to their hand, and may enter their body if they then touch their eyes, nose or mouth.