The most common reason for people to fall ill is when they get a virus or bacteria.
Viruses and bacteria are the most common causes of illness. They are infectious microorganisms that can be transmitted from one person to another. Viruses cannot live outside of a host cell, so they have to infect a cell in order to replicate. This means that if you get sick, it’s likely that you will have been infected by something like a cold or flu virus.
Bacteria can live outside of a host cell and can also cause illness. Bacteria are usually found in the intestines and throat, but they can spread to other parts of the body via saliva or other bodily fluids. It’s possible for bacteria to cause infections in organs such as the kidneys, lungs, and brain.
