They must rely on infecting other cells to produce more viruses.
A virus is too small to see with the naked eye.Theyre found everywhere.
A virus tailored to humans can invade your body, take over your cells, and make you sick.
Yuichiro Chino / Getty Images
Viruses come in many different types.
Not all viruses make people sick.
Sometimes, your immune system can fight them off without you even knowing.
Yuichiro Chino / Getty Images
What Are Viruses?
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.
Viruses infect humans, animals, plants, bacteria, amoeba, and fungi.
If theres a living thing, theres probably a virus that infects it.
The living thing infected by the virus is called its host.
These are called obligate intracellular parasites.
There are many ways to classify viruses.
What Are 5 Common Viruses?
Some common viruses are those that cause:
How Do Viruses Work?
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.
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 cant 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.
In some cases, virtual infections are treated with drugs calledantivirals.
Antibacterial medicines wont help you get better from a virus.
So unless your healthcare provider has confirmed that a bacterial infection is causing your symptoms, avoid taking antibiotics.
Can Viruses Be Prevented?
You may not even notice youve been exposed to a virus if youve 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.
The other significant way to protect yourself against viruses and other germs is to practice good hygiene.
When washing your hands, use warm water and soap for at least 20 seconds.
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.
They can cause disease.
Some viruses cause sickness, like common colds, the flu, and food poisoning.
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.
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