Are Cavities Contagious?

In general, cavities are formed when bacteria stays on the teeth and results in tooth decay. But can you catch a cavity like you can a cold or flu virus?

First off, a cavity is a hole in the tooth forms due to untreated tooth decay. How does tooth decay form in the first place? While most people think it is due to sugary candy, bacteria is the real culprit. Bacteria that is left on food particles in your mouth produce an acid that eats away at your teeth.