Table of ContentsView AllTable of ContentsWhat Are Viruses?Types of VirusHow Do Viruses Work?TransmissionSymptomsTreatmentPrevention
Table of ContentsView All
View All
Table of Contents
What Are Viruses?
Types of Virus
How Do Viruses Work?
Transmission
Symptoms
Treatment
Prevention
Viruses are tiny microbes made of a protein shell with genetic material inside. They must rely on infecting other cells to produce more viruses. A virus is too small to see with the naked eye.They’re found everywhere.
A virus tailored to humans can invade your body, take over your cells, and make you sick. Viruses aren’t considered living organisms themselves because they must use their hosts’ cells to copy their genes and create new viruses.
Viruses come in many different types. Not all viruses make people sick. Sometimes, your immune system can fight them off without you even knowing.
This article will cover what viruses are, the different types of viruses, how viruses work, some common virus examples, virus symptoms, treatment, and prevention.
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A virus is a tiny non-living microbe. It must infect a cell to make copies of itself inside. They have a genome of DNA or RNA inside a shell of proteins. Some of them also have a layer of fats around the protein shell.
Because viruses rely on other living things to make new viruses, don’t make their energy, and don’t grow, they are not typically thought to be alive.There is still some controversy over this because there are other living things that we would traditionally think of as “alive” that rely on a host for energy, replication, or some other factor of their being. These are called obligate intracellular parasites.
More than 200 viruses are known to infect humansfrom 26 virus families.More are discovered every year.
There are many ways to classify viruses.
What Are 5 Common Viruses?
Some common viruses are those that cause:
Viruses use proteins on their outer shell or fatty layer to find and stick to their host cells. They use the proteins to put their genes inside the cell. When there, the genes use the cell’s machinery, make copies of the genes, and build more virus protein shells.
The cells put together new viruses and release them. They go on to infect many more cells, spreading the infection.
How Are Viruses Transmitted?
Viruses can’t move on their own. They depend on host actions to transmit their infections.
Infections are transmitted in many ways, including through:
What Are the Symptoms of a Virus?
When a virus infects you, it may cause symptoms. Some of these symptoms are from the virus, and some are from the immune system fighting back. Depending on what cells of the body are infected, the virus may cause different symptoms.
Some general symptoms of a viral infection include:
How Are Viruses Treated?
Time is the best treatment for most viral infections, including day-to-day colds and stomach flu. Time, rest, and hydration will let your body take care of most viral invaders. Additionally, most people can take fever-reducing medicines like Tylenol (acetaminophen) or Advil (ibuprofen) to help with fevers or pain.
In some cases, virtual infections are treated with drugs calledantivirals. For instance, if you have the flu, your healthcare provider may prescribe the antiviralTamiflu (oseltamivir phosphate)to help you get better quicker.
Antibacterial medicines won’t help you get better from a virus. Takingantibioticswhen you don’t need to also increases the likelihood of creating superbugs that these drugs can no longer affect. So unless your healthcare provider has confirmed that a bacterial infection is causing your symptoms, avoid taking antibiotics.
Can Viruses Be Prevented?
Vaccines can prevent some viral infections.Vaccinesare drugs that prime your body to fight back when it comes into contact with an invading germ. Some vaccines you need to get only once, while others you may need to get every year, like theflu vaccine.
Vaccines typically make the viral infection milder, less dangerous, and make you feel less sick if you do get an infection. You may not even notice you’ve been exposed to a virus if you’ve been vaccinated against it.
Over a dozen vaccines can help you fight off viral infections.People typically get many vaccines during infancy and childhood. Others may be useful during pregnancy or while traveling internationally.
Top 20 Vaccines You Should Know About
The other significant way to protect yourself against viruses and other germs is to practice good hygiene.
The first step to good hygiene is towash your handsoften or use a hand sanitizer with at least 60% alcohol. When washing your hands, use warm water and soap for at least 20 seconds.
This is especially true when you’re:
Generally, staying home if you are sick is a good idea so you don’t risk transmitting your germs to someone else.
Summary
A virus is a tiny non-living microbe. It can break into a cell and take over. It makes copies of itself when inside. Its genome is either DNA or RNA and is inside a protein shell. Some have a layer of fat around the protein shell.
Viruses infect humans, animals, plants, bacteria, amoebas, fungi, and any other living organism they can find. They can cause disease. Some viruses cause sickness, like common colds, the flu, and food poisoning.
Symptoms of a viral infection include fever, pain, nausea, diarrhea, cough, congestion, shortness of breath, rashes, warts, and many others.
The best treatment for most everyday viruses is rest, hydration, and time. In some cases, antivirals may help speed healing. Vaccines can prevent some viral infections.
Otherwise, general hygiene help reduces the number of viruses you catch. Hygiene includes washing hands, avoiding sick people, and wearing a mask.
14 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Taylor MW.What is a virus?Viruses and Man: A History of Interactions. 2014;23-40. doi:10.1007/978-3-319-07758-1_2National Cancer Institute.Virus.Arizona State University.Are viruses alive?California Institute of Technology.How do viruses infect our cells?Siegel RD.Classification of human viruses.Principles and Practice of Pediatric Infectious Diseases. 2018;1044-1048.e1. doi:10.1016/B978-0-323-40181-4.00201-2Louten J.Virus structure and classification.Essential Human Virology. 2016;19-29. doi:10.1016/B978-0-12-800947-5.00002-8MedlinePlus.Viral infections.MedlinePlus.Germs and hygiene.National Institute of Diabetes and Digestive and Kidney Diseases.Symptoms & causes of viral gastroenteritis (“stomach flu").Centers for Disease Control and Prevention.Symptoms of COVID-19.Centers for Disease Control and Prevention.Chickenpox (varicella) signs and symptoms.MedlinePlus.Hepatitis C.Centers for Disease Control and Prevention.List of vaccines used in United States.MedlinePlus.Germs and hygiene.
14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Taylor MW.What is a virus?Viruses and Man: A History of Interactions. 2014;23-40. doi:10.1007/978-3-319-07758-1_2National Cancer Institute.Virus.Arizona State University.Are viruses alive?California Institute of Technology.How do viruses infect our cells?Siegel RD.Classification of human viruses.Principles and Practice of Pediatric Infectious Diseases. 2018;1044-1048.e1. doi:10.1016/B978-0-323-40181-4.00201-2Louten J.Virus structure and classification.Essential Human Virology. 2016;19-29. doi:10.1016/B978-0-12-800947-5.00002-8MedlinePlus.Viral infections.MedlinePlus.Germs and hygiene.National Institute of Diabetes and Digestive and Kidney Diseases.Symptoms & causes of viral gastroenteritis (“stomach flu").Centers for Disease Control and Prevention.Symptoms of COVID-19.Centers for Disease Control and Prevention.Chickenpox (varicella) signs and symptoms.MedlinePlus.Hepatitis C.Centers for Disease Control and Prevention.List of vaccines used in United States.MedlinePlus.Germs and hygiene.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Taylor MW.What is a virus?Viruses and Man: A History of Interactions. 2014;23-40. doi:10.1007/978-3-319-07758-1_2National Cancer Institute.Virus.Arizona State University.Are viruses alive?California Institute of Technology.How do viruses infect our cells?Siegel RD.Classification of human viruses.Principles and Practice of Pediatric Infectious Diseases. 2018;1044-1048.e1. doi:10.1016/B978-0-323-40181-4.00201-2Louten J.Virus structure and classification.Essential Human Virology. 2016;19-29. doi:10.1016/B978-0-12-800947-5.00002-8MedlinePlus.Viral infections.MedlinePlus.Germs and hygiene.National Institute of Diabetes and Digestive and Kidney Diseases.Symptoms & causes of viral gastroenteritis (“stomach flu").Centers for Disease Control and Prevention.Symptoms of COVID-19.Centers for Disease Control and Prevention.Chickenpox (varicella) signs and symptoms.MedlinePlus.Hepatitis C.Centers for Disease Control and Prevention.List of vaccines used in United States.MedlinePlus.Germs and hygiene.
Taylor MW.What is a virus?Viruses and Man: A History of Interactions. 2014;23-40. doi:10.1007/978-3-319-07758-1_2
National Cancer Institute.Virus.
Arizona State University.Are viruses alive?
California Institute of Technology.How do viruses infect our cells?
Siegel RD.Classification of human viruses.Principles and Practice of Pediatric Infectious Diseases. 2018;1044-1048.e1. doi:10.1016/B978-0-323-40181-4.00201-2
Louten J.Virus structure and classification.Essential Human Virology. 2016;19-29. doi:10.1016/B978-0-12-800947-5.00002-8
MedlinePlus.Viral infections.
MedlinePlus.Germs and hygiene.
National Institute of Diabetes and Digestive and Kidney Diseases.Symptoms & causes of viral gastroenteritis (“stomach flu").
Centers for Disease Control and Prevention.Symptoms of COVID-19.
Centers for Disease Control and Prevention.Chickenpox (varicella) signs and symptoms.
MedlinePlus.Hepatitis C.
Centers for Disease Control and Prevention.List of vaccines used in United States.
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