Viruses cause many different diseases, such as the common cold, hepatitis, herpes, mumps, chickenpox, shingles and AIDS.

Bacteria can cause illnesses such as strep throat and urinary tract infections (UTIs). Fungi mainly cause skin diseases such as athlete’s foot and ringworm, but other types can affect your nervous system or lungs.

You can catch an infectious disease through direct contact with someone who is sick (examples are STIs and mothers passing germs to their babies) or through indirect contact such as drinking from a glass someone who has a cold used and didn't wash. You can be infected by an animal or insect bite, or by consuming contaminated food or water.

While each infectious disease has its own symptoms, there are some common ones including cough, diarrhea, fatigue, aches and fever.

You can prevent many infectious diseases by frequently washing your hands, understanding proper food-safety techniques and ensuring your vaccinations are up to date. Infectious diseases such as measles and chickenpox can be prevented by vaccines.