Virus
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
Latest about Viruses, Infections & Disease
Leprosy is rare but on the rise in Florida — here's what to know
By Robert A. Schwartz published
An expert explains leprosy, an ancient disease caused by two different bacteria, one of which was only identified in 2008.
Deadly amoeba brain infection can result from unsafe nasal rinsing, CDC warns
By Emily Cooke published
A CDC report describes 10 patients infected by an amoeba after conducting a nasal rinse, three of whom died from a nervous-system infection.
Paul Alexander, polio survivor who lived in iron lung for 70 years, dies age 78
By Emily Cooke published
Paul Alexander was one of the last people to use an iron lung, having been left unable to breathe on his own after catching polio in the 1950s.
300 people possibly exposed to measles at California hospital
By Emily Cooke published
Officials are trying to contact around 300 people who may have been exposed to measles at the UC Davis Medical Center Emergency Department on March 5, when an infected child was treated there.
COVID pandemic knocked 1.6 years off global life expectancy, study finds
By Sascha Pare published
Global life expectancy had been on the rise since 1950, but this historical trend was reversed between 2019 and 2021, at the height of the COVID-19 pandemic.
Parasitic worms found in man's brain after he likely ate undercooked bacon
By Emily Cooke published
A middle-aged man in the U.S. developed a parasitic infection in his brain after eating undercooked bacon.
'Parrot fever' outbreak in 5 European countries kills 5 people
By Emily Cooke published
Most people involved in the current parrot fever outbreak developed the disease after being exposed to infected wild or pet birds, the WHO said.
A branch of the flu family tree has died and won't be included in future US vaccines
By Nicoletta Lanese published
Advisers to the FDA say a type of flu virus known as the "Yamagata lineage" can be dropped from next year's vaccines.
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