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
'Wake-up call' as hookworm parasites that infect pets and people grow drug resistant
By Patrick Pester published
Hookworms that cause deadly dog infection and 'creeping eruption' in humans are growing resistant to drugs.
Tularemia: The 'rabbit fever' that can fatally infect humans
By Emily Cooke published
Tularemia, or "rabbit fever," is an infectious disease that normally affects animals but can spread to humans, sometimes via tick and deer fly bites.
'Reanimated' herpes viruses lurking in the brain may link concussions and dementia
By Nicoletta Lanese published
A study using lab-made models of the brain suggests that a herpes virus may be a key link between concussions and dementia risk.
Never-before-seen parasite is resistant to ivermectin
By Pandora Dewan published
Trichuris incognita is a newfound intestinal roundworm closely related to the whipworm parasite. However, it is significantly more resistant to treatment.
1st deadly case of H5N1 bird flu reported in US
By Nicoletta Lanese published
The patient in Louisiana who contracted a severe case of bird flu has died, officials announced.
What's the best way to kill norovirus, the 'stomach bug'?
By Skyler Ware published
Only certain cleaners kill norovirus, a leading cause of vomiting, diarrhea and foodborne illness. Why is that?
Viral disease HMPV is on the rise among kids in China — what is it?
By Pandora Dewan published
Health officials have reported a rise in human metapneumovirus (HMPV) infections among children ages 14 and under in China, but the exact magnitude of this uptick is unclear.
Pet cats in Los Angeles County are catching bird flu from raw food, milk
By Nicoletta Lanese published
The Los Angeles County Department of Public Health has warned that raw pet food products have tested positive for bird flu and sickened pet cats in the area.
Healthy breast cells can look like invasive cancer, complicating early diagnosis
By Kristel Tjandra published
Scientists found that healthy women can carry genetic changes in their breast cells that are thought to be characteristic of invasive breast cancer.
Situs inversus: The condition where your organs are on the 'wrong' side
By Emily Cooke published
Situs inversus is a rare genetic condition that causes the organs in the chest and abdomen to be located on the opposite side from where they're usually found, like a mirror image.
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