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Overview of Viral Infections

By

The Manual's Editorial Staff

Reviewed/Revised Feb 2024
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A virus is a microorganism, a tiny living organism. Other common microorganisms include bacteria Introduction to Bacteremia, Sepsis, and Septic Shock Bacteremia, sepsis, severe sepsis, and septic shock are related: Bacteremia: Bacteria are present in the bloodstream. Bacteremia can result from a serious infection or from something as harmless... read more . Viruses are much smaller than bacteria and can be seen only with the most powerful microscopes.

Unlike bacteria, viruses can't reproduce on their own. So when viruses get into your body, they take over certain cells Cells Cells are the basic building blocks of the body. All tissues and organs are made of billions of different cells. Human cells vary in size, but all are quite small. Even the largest, a fertilized... read more Cells and use structures in those cells to make more copies of the virus. This usually damages and then kills the cell. However, some viruses can stay inside cells for a long time without killing them.

There are thousands of different viruses. Some viruses infect people. Other viruses infect only animals. Only a few viruses can infect both people and animals.

What is a viral infection?

A viral infection is a sickness caused by a virus.

How can doctors tell if I have a viral infection?

Doctors can tell if you have certain common viral infections based on your symptoms. They may also do:

  • Blood tests

  • Cultures (when doctors take a sample from your body and try to grow germs from it in a lab)

How do doctors treat viral infections?

Doctors can’t usually do much to treat many viruses. They’ll mainly suggest medicines to treat your symptoms and help you feel better. For example, if you have a stuffy nose, doctors may tell you to take a decongestant.

For some viruses, doctors can give you an antiviral medicine. Antiviral medicines are used for only a few viruses, including:

Antibiotics are drugs that kill bacteria. Antibiotics do not kill viruses.

How can I prevent viral infections?

NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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