Question: why do diseases spread

Rory Miles answered on 11 Mar 2014:

There are many different reasons why diseases can spread. I’ll use a cold as an example. Colds spread as when people sneeze, other people around them can breathe the cold bugs in, causing them to have a cold. Sometimes, particular cold bugs might become better than other cold bugs and be better at spreading to many other people (Scientists call this an epidemic). Another example, norovirus, the disease that often leads to vomiting in winter, can actually be transferred to people on door handles if they don’t wash their hands properly. Different diseases spread in different ways and its mainly used as a way for bugs to continue to survive.