An infection occurs when germs or pathogens invade and then grow in the body. Possible infection-causing germs include viruses, bacteria, fungi, yeast, and other microorganisms.
An infection can begin in any one part of the body and may then spread to other regions.
When someone has an infection, there are common symptoms that they may experience, including:
- runny nose
- upset stomach
- muscle aches
- swollen lymph nodes
Some symptoms are also specific to the type of pathogen causing the infection and the part of the body affected by it.