Viral infection is the invasion of the body by a small agent known as a virus. Viruses replicate inside host cells and can produce toxins that cause disease. The immune system helps to destroy viruses ...

E. coli bacteria from your skin or rectum are common causes of UTIs. UTIs often require antibiotics to treat and prevent serious complications like kidney damage. Holding in your pee can create an ...

Mark Gurarie is a writer covering health topics, technology, music, books, and culture. He also teaches health science and research writing at George Washington University's School of Medical and ...