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.
Latest about Viruses, Infections & Disease
The 10 deadliest cancers, and why there's no cure
The deadliest cancers aren't necessarily the ones that kill the most people overall; they're the ones with the lowest survival rates.
Woman's sudden hearing loss turned out to be a tick lodged in her ear canal
The tick was found lodged in the skin of her left ear canal after a thorough examination by her doctors.
New treatment for most aggressive brain cancer may help patients live longer
Glioblastoma often kills within months. A new targeted radiation therapy may help patients live longer.
'Wake-up call' as hookworm parasites that infect pets and people grow drug resistant
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
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
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
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
The patient in Louisiana who contracted a severe case of bird flu has died, officials announced.
