Add Yahoo as a preferred source to see more of our stories on Google. Bacteria and viruses are often lumped together as germs, and they share many characteristics. They’re invisible to the human eye.

DEAR DR. ROACH: I watched a show that described how a virus invades a cell and found it fascinating. What is the difference between a virus and a bacterial infection? -- G.D. ANSWER: Viral infections ...

According to the Meningitis Research Foundation, Viral meningitis is the most common form in adults and older children and is ...

Viruses in man-made environments cause public health concerns, but they are generally less studied than bacteria. A recent study led by environmental scientists from City University of Hong Kong ...