Virus

A virus is a microscopic infectious agent that can reproduce only inside a host cell. Viruses infect all types of organisms: from animals and plants, to bacteria and archaea. Since the initial discovery of tobacco mosaic virus by Martinus Beijerinck in 1898, more than 5,000 types of virus have been described in detail, although most types of virus remain undiscovered. Viruses are ubiquitous, as they are found in almost every ecosystem on Earth, and are the most abundant type of biological entity on the planet. The study of viruses is known as virology, and is a branch of microbiology.

What is a Virus?

A virus is a small infectious agent that can only replicate inside the cells of another organism. The word is from the Latin ''virus'' referring to poison and other noxious substances, first used in English in 1392. ''Virulent'', from Latin ''virulentus'' (poisonous), dates to 1400. A meaning of "agent that causes infectious disease" is first recorded in 1728, The term ''virion'' is also used to refer to a single infective viral particle. The plural is "viruses".

Virus History

Virus Origins

Virus Microbiology

Virus Classification

Virus Infection in Other Species

Human Diseases Caused by Viruses

Virus Uses in Virology

Virus Purification Methods

Latest Virus News and Research

Nurses and doctors sick with COVID feel pressured to get back to work

The first call in early April was from the testing center, informing the nurse she was positive for COVID-19 and should quarantine for two weeks.

12 Aug 2020

C-type lectin receptors play a role in SARS-CoV-2 infection

A new study published on the preprint server bioRxiv in August 2020 confirms and extends earlier findings showing that a type of sugar-based receptor on innate immune cells promotes the entry of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into other cells that carry the viral receptor, angiotensin-converting enzyme 2 (ACE2).

12 Aug 2020

Study: High blood sugar may trigger worse outcomes in COVID-19 patients

As COVID-19 continues to rage across the U.S., researchers are digging deeper into how the virus wreaks havoc on the body, especially for those with a pre-existing chronic illness.

12 Aug 2020

Study reveals new clues about SARS-CoV-2 infection

Working together, researchers at McMaster University and the University of Waterloo are searching for how the SARS-CoV-2 virus infects the lungs - and they're challenging what has become an accepted truth about the virus.

12 Aug 2020

Open access journal posts COVID-19 preprint studies to reduce misinformation

Today, open access journal Rapid Reviews: COVID-19 (RR:C19), published by the MIT Press, posted peer reviews of eight COVID-19 preprint studies in an effort to reduce misinformation and to elevate noteworthy and useful research for scientists, public health officials, journalists, and the public.

12 Aug 2020

New model predicts which COVID-19 patients are at higher risk for hospitalization

Cleveland Clinic researchers have developed and validated a risk prediction model (called a nomogram) that can help physicians predict which patients who have recently tested positive for SARS-CoV-2, the virus that causes COVID-19, are at greatest risk for hospitalization.

12 Aug 2020

Research looks at convalescent plasma use in COVID-19 mouse model

A new study by researchers at the University of Iowa and published on the preprint server bioRxiv in August 2020 reports the utility of a mouse model that recapitulates several aspects of human COVID-19 and can reflect the antiviral efficacy of new drugs as well.

12 Aug 2020

SARS-CoV-2 a "swarm" of mutant viruses

In this new study, the virus was serially passaged in independent cell types in a controlled environment. The researchers found that the virus rapidly adapts to the changing conditions in culture by selecting for pre-existing species.

12 Aug 2020

Study highlights need to understand different environmental conditions that affect surface chemistry of SARS-CoV-2

Researchers at Michigan Tech, TÜV SÜD UK National Engineering Laboratory and University of Edinburgh call for increased research on virus surface stability and interaction in "Surface Chemistry Can Unlock Drivers of Surface Stability of SARS-CoV-2 in Variety of Environmental Conditions" in the Cell Press journal Chem.

12 Aug 2020

Can SARS-CoV-2 be transmitted via feces?

A new study by researchers at the University of Oxford and the Trip Medical Database and published on the preprint server medRxiv* in August 2020 as part of the ongoing Open Evidence Review on Transmission Dynamics of COVID-19 reports the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in feces and the need for precautions to prevent orofecal spread in the surroundings of confirmed or suspected cases.

12 Aug 2020

Smoking and vaping significantly increase risk of COVID-19 in teens and young adults

Now, a new study published in the Journal of Adolescent Health shows that teens and young adults may have a heightened risk of COVID-19 if they vape or smoke cigarettes. Cigarette smokers are seven times more likely to be infected with SARS-CoV-2. Meanwhile, people who vape are five times more likely to be diagnosed with the viral infection.

11 Aug 2020

Scientist explains why COVID-19 targets only some organs while others are spared

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses the enzyme angiotensin-converting enzyme 2 (ACE2) to enter and infect human cells. It causes COVID-19 and can lead to a multitude of complications, including multi-organ impairment, partially due to the abundant expression of ACE2 in all human tissues.

11 Aug 2020

Focusing on human enzymes and not SARS-CoV-2 could help treat COVID-19

Now, breakthrough research into malaria suggests targeting enzymes from the human host, rather than from the pathogen itself. The new research could pave the way for effective treatments for a wide range of infectious diseases, including the coronavirus disease (COVID-19).

11 Aug 2020

Researchers uncover a new vulnerability in the novel coronavirus' infamous spike protein

Northwestern University researchers have uncovered a new vulnerability in the novel coronavirus' infamous spike protein -- illuminating a relatively simple, potential treatment pathway.

11 Aug 2020

Natural compund in cedar and grapefruit skin could help repel mosquitoes and ticks says CDC

Over the last few years, there has been a rise in the number of cases of diseases caused by mosquito and tick bites. The U.S. Centers for Disease Control and Prevention (CDC) has said that a natural chemical compound could help combat this problem. This compound Nootkatone is found commonly in cedar trees, and grapefruit skin says the organization.

11 Aug 2020

Inhaled delivery of a potent neutralizing nanobody effective against SARS-CoV-2

A recent study by researchers from China, available on the bioRxiv preprint server, shows how stable neutralizing nanobody Nb11-59 might be a promising prophylactic and therapeutic molecule against coronavirus disease (COVID-19) – especially if administered via the inhalatory route.

11 Aug 2020

Study to examine possible effects of COVID-19 on dementia risk in older adults

In addition to its clear impact on physical health, COVID-19 may also have adverse consequences for brain health. Therefore, researchers at Baycrest's Rotman Research Institute (RRI) are investigating the possible effects of COVID-19 and infection prevention measures on dementia risk in older adults.

11 Aug 2020

Stanford study reveals immunological deviations and lapses in severe COVID-19 cases

Some people get really sick from COVID-19, and others don't. Nobody knows why.

11 Aug 2020

Protein uses two different mechanisms to inhibit viral infections

To protect humans against infection, a protein called MARCH8 tags the vesicular stomatitis virus (VSV) for destruction while it merely holds HIV hostage, a new study in eLife shows.

11 Aug 2020

Public health officials are quitting or getting fired in throes of pandemic

Vilified, threatened with violence or in some cases suffering from burnout, dozens of state and local public health officials around the U.S. have resigned or have been fired amid the coronavirus outbreak, a testament to how politically combustible masks, lockdowns and infection data have become.

11 Aug 2020