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

Did California's pediatric COVID-19 vaccination program reduce reported cases and hospitalizations?

Changes in the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and related hospitalizations.

26 Apr 2024

Personalized risk prediction tool helps prioritize high-risk infants for RSV prevention

A new tool to identify infants most at risk for severe respiratory syncytial virus (RSV) illness could aid pediatricians in prioritizing children under 1 to receive a preventive medication before RSV season (October-April), according to Vanderbilt University Medical Center (VUMC) research published in Open Forum Infectious Diseases and to be presented at the American Thoracic Society 2024 International Conference.

25 Apr 2024

Genetically modified mice reveal key players in immune defense against viruses

Chemokines are signaling proteins that orchestrate the interaction of immune cells against pathogens and tumors.

25 Apr 2024

MIT study reveals circadian impact on drug metabolism in engineered livers

Giving drugs at different times of day could significantly affect how they are metabolized in the liver, according to a new study from MIT.

25 Apr 2024

Putting genomic surveillance of pathogens at the forefront of future pandemic preparedness

The Covid-19 pandemic turned the world upside down. In fighting it, one of our most important weapons was genomic surveillance, based on whole genome sequencing, which collects all the genetic data of a given microorganism.

25 Apr 2024

Bivalent COVID-19 vaccine boosts immunity but needs to be updated

A major bivalent COVID-19 vaccine induces production of neutralizing antibodies against the coronavirus that circulated at the start of the pandemic as well as subvariants of omicron, albeit less abundantly, according to a Brazilian study reported in the Journal of Medical Virology.

25 Apr 2024

154 million lives saved: Landmark study highlights power of vaccination

A major landmark study to be published by The Lancet reveals that global immunization efforts have saved an estimated 154 million lives – or the equivalent of 6 lives every minute of every year – over the past 50 years.

25 Apr 2024

Paclitaxel treatment found to directly promote HBV replication and transcription

Hepatitis B virus (HBV) reactivation is commonly observed in individuals with chronic HBV infection undergoing antineoplastic drug therapy.

24 Apr 2024

Giant virus takes down deadly brain parasite

The single-celled organism Naegleria fowleri ranks among the deadliest human parasites. Researchers around Matthias Horn and Patrick Arthofer from the Center for Microbiology and Environmental Systems Science at the University of Vienna, in an international collaboration, have discovered viruses that infect this harmful microbe.

24 Apr 2024

MSU team creates a promising vaccine candidate for antibiotic-resistant bacteria

Driven by the overuse of antimicrobials, pathogens are quickly building up resistances to once-successful treatments.

24 Apr 2024

New tARC-seq method enhances precision in tracking SARS-CoV-2 mutations

A tARC-seq approach to precisely determine SARS-CoV-2 mutation frequency.

24 Apr 2024

Repurposed nasal antibiotic neomycin shows promise in preventing and treating respiratory viral infections

Intranasal administration of neomycin sulfate in murine models shows promise as a prophylactic and therapeutic agent against respiratory viruses like influenza A and SARS-CoV-2 by inducing interferon-stimulated gene (ISG) expression, independent of microbiota and interferon activation.

24 Apr 2024

Innovative peptide-based hydrogel therapy for virus prevention

Vaccines remain the gold standard of protection against dangerous pathogens, but take considerable time and vast resources to develop.

23 Apr 2024

Research highlights best window for paxlovid administration in COVID-19 patients

Researchers have described the optimal timing for COVID-19 patients to take the antiviral, Paxlovid, to get the most benefit from the treatment, according to a study published April 16 in eLife.

23 Apr 2024

Analysis finds significant variations in national COVID-19 treatment recommendations

National clinical guidelines for the treatment of COVID-19 vary significantly around the world, with under-resourced countries the most likely to diverge from gold standard (World Health Organization; WHO) treatment recommendations, finds a comparative analysis published in the open access journal BMJ Global Health.

23 Apr 2024

Cost becomes a significant factor in smoking cessation efforts

Health concerns are still the primary motive for more than half of those who say they want to stop smoking in England, but cost is now a key factor for more than 1 in 4, finds an analysis of national survey responses, published in the open access journal BMJ Public Health.

23 Apr 2024

Bacteriophage-derived lysin could be used to target odor-causing bacteria in armpits

Body odor from the armpits comes from bacteria metabolizing sweat produced by the apocrine glands. These bacteria are native to our skin, but the odors produced differ among people.

23 Apr 2024

Study discovers hidden mechanism behind rapid COVID variants

The SARS-CoV-2 virus that causes COVID has the unsettling ability of often generating variants of itself. Other viruses also mutate, but as SARS-CoV-2 quickly spread throughout the entire human population during the pandemic, killing millions, the virus' dynamic evolution posed a serious problem: it repeatedly challenged our bodies' immune response fighting the virus and hindered the process of getting updated vaccines ready.

23 Apr 2024

University of Arizona researchers awarded $1.8M grant to investigate HPV's cellular invasion

Researchers at the University of Arizona College of Medicine – Tucson were awarded a $1.8 million grant by the National Institute of General Medical Sciences, a division of the National Institutes of Health, to learn how human papillomavirus makes its way to a cell's nucleus.

22 Apr 2024

Blood test may predict MS development, UCSF research reveals

In a discovery that could hasten treatment for patients with multiple sclerosis (MS), UC San Francisco scientists have discovered a harbinger in the blood of some people who later went on to develop the disease.

22 Apr 2024