Medical definition of Infection

Infection: The invasion and multiplication of microorganisms such as bacteria, viruses, and parasites that are not normally present within the body. An infection may cause no symptoms and be subclinical, or it may cause symptoms and be clinically apparent. An infection may remain localized, or it may spread through the blood or lymphatic vessels to become systemic (bodywide). Microorganisms that live naturally in the body are not considered infections. For example, bacteria that normally live within the mouth and intestine are not infections.
An infection occurs when another organism enters your body and causes disease. The organisms that cause infections are very diverse and can include things like viruses, bacteria, fungi, and parasites.
You can acquire an infection in many different ways, such as directly from a person with an infection, via contaminated food or water, and even through the bite of an insect.
Let’s take a closer look at infections, the types of organisms that cause them, and actions you can take to help prevent becoming ill.
Viral infections
Viruses are very tiny infectious organisms. They’re even smaller than bacteria. On the most basic level, a virus is composed of a piece of genetic material that’s surrounded by a protein shell. Some viruses may have an additional envelope or other features on their surface.
Viruses are parasitic and require a host cell in which to carry out their life cycle. Once the virus has entered the host cell, it’s able to use cellular components to reproduce. New viruses are released from the host cell, a process that’ll sometimes cause the host cell to die.
Possible treatments:
Most of the time, the treatment of viral infections centers on relieving symptoms until your immune system clears the infection.
In some cases, antiviral drugs may be available to help treat a viral infection. Some examples of viral infections for which antivirals are available include HIV, herpes, and hepatitis C.
Some viruses stay with you for life once you’ve been infected. They can lie dormant within your body and may reactivate. Some examples include herpes simplex virus (HSV) and varicella-zoster virus (VZV).
Media Contact:
Allison Grey
Journal Manager
Journal of Infectious Diseases and Diagnosis
Email: jidd@microbialjournals.com