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.

What is the Difference Between Bacteria and 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

What are Filoviruses?

Antiviral Immunity and COVID-19

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What is Vertical Transmission?

What is a Viral Mutation?

What are Viral Clades?

Are Viruses a Lifeform?

What Are Giant Viruses?

Virus Eradication, Extinction, and Elimination Explained

Latest Virus News and Research

Research confirms no association between SARS-CoV-2 and childhood asthma diagnoses

Whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection influences children's asthma risk.

16 Apr 2024

Study shows potential for universal flu vaccine with broad antibody response

Study discusses the potential of universal influenza vaccines, emphasizing the importance of antibody breadth and Fc receptor (FcR) effector functions in protecting against various influenza strains, including those with pandemic potential.

15 Apr 2024

Novel vaccine approach effective against all virus strains

Scientists at UC Riverside have demonstrated a new, RNA-based vaccine strategy that is effective against any strain of a virus and can be used safely even by babies or the immunocompromised.

15 Apr 2024

Canada unlikely to eliminate Hepatitis C by 2030, study finds

Canada will not reach the original World Health Organization's (WHO) target of eliminating the Hepatitis C virus (HCV) by 2030 and lags in comparison to other developed countries, a new study led by researchers at the University of Waterloo has found.

15 Apr 2024

Antibiotics ineffective for cough treatment in lower respiratory tract infections

Use of antibiotics provided no measurable impact on the severity or duration of coughs even if a bacterial infection was present, finds a large, prospective study of people who sought treatment in U.S. primary or urgent care settings for lower-respiratory tract infections.

15 Apr 2024

Texas A&M scientists elucidate how phages disarm antibiotic-resistant bacteria

Bacterial infections pose significant challenges to agriculture and medicine, especially as cases of antibiotic-resistant bacteria continue to rise.

15 Apr 2024

Study reveals age-specific differences in nasal cells' response to SARS-CoV-2

Important differences in how the nasal cells of young and elderly people respond to the SARS-CoV-2 virus, could explain why children typically experience milder COVID-19 symptoms, finds a new study led by researchers at UCL and the Wellcome Sanger Institute.

15 Apr 2024

Breast milk's secret weapon against RSV revealed in new study

Researchers explored how human milk oligosaccharides (HMOs) protect infants from respiratory syncytial virus (RSV), suggesting that these components in breast milk may prevent or reduce the severity of RSV infections through multiple mechanisms including gut microbiome modulation and direct antiviral actions.

15 Apr 2024

SARS-COV-2 infection not linked to increased risk of asthma development in pediatric patients

In the wake of the COVID-19 pandemic, many families worried about the long-term effects posed by the SARS-COV-2 virus.

13 Apr 2024

Cas13d-NCS: A game-changer in RNA virus defense

The rise of RNA viruses like SARS-CoV-2 highlights the need for new ways to fight them. RNA-targeting tools like CRISPR/Cas13 are powerful but inefficient in the cytoplasm of cells, where many RNA viruses replicate.

13 Apr 2024

Study reveals metabolic markers linked to long COVID-19 severity

Long COVID-19, or post-acute sequelae of SARS-CoV-2 infection (PASC), is a global health phenomenon characterized by persistent symptoms following the acute phase of COVID-19.

13 Apr 2024

Unveiling the key role of RNA modification in HIV-1 survival and replication

A chemical modification in the HIV-1 RNA genome whose function has been a matter of scientific debate is now confirmed to be key to the virus's ability to survive and thrive after infecting host cells, a new study has found.

12 Apr 2024

New genetic variants could raise a woman's risk of cervical cancer from HPV infections

Human papillomavirus (HPV) is the second most common cancer-causing virus, accounting for 690,000 cervical and other cancers each year worldwide.

12 Apr 2024

Annual COVID-19 vaccine proves to be a wise investment for personal health and pocketbook

Study finds that receiving an annual COVID-19 vaccine is clinically and economically beneficial for individuals, regardless of insurance status, offering savings by reducing the likelihood of infection and its associated costs.

11 Apr 2024

Older adults' social patterns shift post-pandemic, study finds

Years after the U.S. began to slowly emerge from mandatory COVID-19 lockdowns, more than half of older adults still spend more time at home and less time socializing in public spaces than they did pre-pandemic, according to new University of Colorado Boulder research.

10 Apr 2024

Researchers create novel drug that can prevent flu-induced lung injury

Infection with the influenza virus leads to lung injury through inflammation over-activation that causes collateral damage to cells required for breathing.

10 Apr 2024

Human-wildlife interface: Starling movements linked to E. coli carriage

Research unveils how spotless starlings' movements, monitored via GPS, relate to the carriage and potential spread of Escherichia coli (E. coli), emphasizing the significant role of bird movement patterns in transmitting pathogens across different environments.

10 Apr 2024

Unraveling the complex web of rectal infections and the microbiome in MSM

Study delves into the relationships between various sexually transmitted infections, including Neisseria gonorrhoeae, Chlamydia trachomatis, Torquetenovirus, and high-risk HPV, and their effects on the anorectal microbiome among men who have sex with men (MSM), unveiling complex interactions that may influence infection outcomes and treatment strategies.

10 Apr 2024

Study reveals unexpected vulnerability of lung immune cells to SARS-CoV-2

The lung-cell type that's most susceptible to infection by SARS-CoV-2, the virus that causes COVID-19, is not the one previously assumed to be most vulnerable.

10 Apr 2024

Sugar abnormalities in the blood may promote biological aging and inflammation in HIV patients

The Wistar Institute's associate professor Mohamed Abdel-Mohsen, Ph.D., along with his team and collaborators, has identified sugar abnormalities in the blood that may promote biological aging and inflammation in people living with HIV (PLWH).

10 Apr 2024