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
'Vampire' bacteria thirst for human blood — and cause deadly infections as they feed
By Emily Cooke published
Several bacteria that can cause deadly bloodstream infections in humans are attracted to an amino acid in our blood, scientists have discovered.
Cancer patients can now be 'matched' to best treatment with DNA and lab-dish experiments
By Diana Azzam published
Identifying the most effective cancer treatment for a given patient from the get-go can help improve outcomes.
The 10 deadliest cancers, and why there's no cure
By Ashley P. Taylor, Emily Cooke last updated
reference The deadliest cancers aren't necessarily the ones that kill the most people, overall. They're the ones with the lowest survival rates.
Parasite that lived in woman's eye for 2 years likely came from crocodile meat
By Nicoletta Lanese published
Doctors described a case of a rare infection called ocular pentastomiasis, which is caused by a parasite known to lay its eggs in snakes.
New cause of asthma lung damage revealed
By Emily Cooke published
In a lab study, scientists have pinpointed a potential way to "break the inflammatory cycle" of asthma.
Man in critical condition after catching deadly 'B virus' from wild monkeys in Hong Kong
By Nicoletta Lanese published
As of April 3, the man infected with B virus was still being treated in the ICU, health officials said.
Bite from toilet rat hospitalizes man in Canada
By Emily Cooke published
Doctors believe the man was likely infected with bacteria in the rat's mouth.
H5N1: What to know about the bird flu cases in cows, goats and people
By Nicoletta Lanese published
Bird flu in cows and goats has raised alarm in the U.S. To date, one person is thought to have caught the virus from cattle, but the risk to the public is low.
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