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

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

Study reveals key protein's role in balancing immune response to viral infections

Researchers have revealed the regulatory mechanism of a specific protein that plays a key role in balancing the immune response triggered by viral infections in mammal cells.

18 Apr 2024

Aging affects immune response and virus dynamics in COVID-19 patients, study finds

A study examining 1031 hospitalized COVID-19 patients found that aging significantly impacts immune responses, viral dynamics, and the nasal microbiome, with older adults experiencing more severe disease symptoms and delayed viral clearance.

18 Apr 2024

Research highlights emergence of immune-evasive SARS-CoV-2 variants in immunocompromised patients

New research to be presented at next week's ESCMID Global Congress (formerly ECCMID) in Barcelona, Spain (27-30 April) highlights the risk of new immune-evasive SARS-CoV-2 variants emerging in immunocompromised patients.

18 Apr 2024

Metabolic health determines effectiveness of influenza vaccination

Metabolic health (normal blood pressure, blood sugar and cholesterol levels, among other factors) influences the effectiveness of influenza vaccinations. Vaccination is known to be less effective in people with obesity compared to those with a healthier body mass index (BMI), but St. Jude Children's Research Hospital scientists have found it is not obesity itself, but instead metabolic dysfunction, which makes the difference.

18 Apr 2024

Researchers receive NIH grant to help develop gene therapy for HIV

Researchers at Washington University School of Medicine in St. Louis have received a $6.2 million grant from the National Institutes of Health (NIH) to develop a gene therapy that would modify the immune system's B cells to spur them to produce broadly neutralizing antibodies against HIV.

18 Apr 2024

Tracking arboviruses by nanopore sequencing of mosquitoes

The technology used to sequence SARS-CoV-2 at record speed early in the COVID-19 pandemic has been successfully tested as a technique to monitor arboviruses and diseases transmitted mainly by mosquitoes.

17 Apr 2024

Vaccines targeting chronic diseases show promise in combatting age-related conditions

Vaccine-based therapeutics for age-related disorders.

17 Apr 2024

Vitamin D deficiency persists despite easy access, review suggests need for tailored supplements

Researchers in a study published in the journal Nutrients delve into the pervasive issue of vitamin D deficiency and its link to various health conditions, advocating for precision nutrition and personalized supplementation to enhance vitamin D intake and effectiveness.

17 Apr 2024

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