A virus is defined as any of a various number of submicroscopic parasites that can infect any animal, plant or bacteria and often lead to very serious or even deadly diseases. A virus consists of a core of RNA or DNA, generally surrounded by a protein, lipid or glycoprotein coat, or some combination of the three. No virus can replicate without the help of a host cell, and though they can be spread, viruses lack the ability of self-reproduction and are not always considered to be living organisms in the regular sense.Some of the most common or best known viruses include the human immunodeficiency virus (HIV), which is the virus that causes AIDS, the herpes simplex virus, which causes cold sores, smallpox, multiple sclerosis, and the human papilloma virus, now believed to be a leading cause of cervical cancer in adult women. The common human cold is also caused by a virus.Since a great deal of mystery still surrounds the origins of most modern viruses, ways to cure these viruses and the diseases they cause are still in the very early stages of development.
Explore Viruses, Infections & Disease
A new analysis of screening tests for four types of cancer suggests that only one actually increases life span, on average. But what do scientists think?
New COVID vaccines have been approved to guard against coronavirus variants that are currently circulating.
Cancer treatments aim to kill tumor cells, and the immune system is tasked with getting rid of the resulting corpses.
An immune-related gene variant has been tied to a reduced risk of Alzheimer's and Parkinson's across a huge, diverse population of people.
The topographical features of DNA in the body may dictate where and when cancer-causing mutations appear in its code.
A rise in RSV cases in Florida and Georgia signals that the nationwide RSV season will soon begin.
In a new study, stopping skeletal-muscle cancer cells from making a specific protein forced them to turn into healthy muscle cells.
Vibrio vulnificus infections normally occur in warmer waters in the Gulf Coast, but rising global coastal sea temperatures have made infections in the eastern U.S. more common.
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