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

What RFK Jr. might face in his nomination hearings this week

President Donald Trump has nominated Robert F. Kennedy Jr., an environmental lawyer with no formal medical or public health expertise, as secretary of Health and Human Sciences.

28 Jan 2025

Exposure to diverse news sources increases vaccine uptake

People who get their news from an ideologically diverse array of sources are more likely to get vaccinated, regardless of their political affiliation, new University of Colorado Boulder research shows.

27 Jan 2025

New therapy shows promise in treating basal cell carcinoma

Basal cell carcinomas, the most common form of skin cancer, occur in chronically sun-exposed areas such as the face.

27 Jan 2025

Updated guidelines for preventing and managing hepatitis B virus reactivation

Researchers update clinical practice guidelines for how to prevent and monitor hepatitis B virus reactivation.

27 Jan 2025

How fruit fly genetics could change the fight against mosquito diseases

How fruit flies mate may hold a key to limiting the spread of diseases by mosquitoes.

25 Jan 2025

Innovative approach tracks SARS-CoV-2 in the blood to guide COVID-19 treatment

Investigators from Mass General Brigham have found that a method originally designed for cancer detection can also identify and monitor even tiny amounts of SARS-CoV-2 intact viral particles in blood and other fluids from patients with acute COVID-19 infections, creating the potential for guiding future treatment of patients. The research is published in Science Advances.

25 Jan 2025

Mapping the human virome to improve disease prevention and treatment

You, my friend, are what scientists call a "holobiont"- an organism made up of human cells and the multiplicity of microscopic species living inside you and on your body.

24 Jan 2025

HPV16 vaccine shows promise in treating precancerous cervical lesions

A therapeutic vaccine targeting human papillomavirus type 16 (HPV16) induced regression in high-grade precancerous cervical lesions, according to the results from a phase II clinical trial published in Clinical Cancer Research, a journal of the American Association for Cancer Research.

24 Jan 2025

New $20 million NIH grant aims to uncover the secrets of the human virome

Unlocking knowledge about the vast and varied collection of viruses that live in and on our bodies is the goal of a $20 million grant from the Common Fund of the National Institutes of Health (NIH) to researchers, including a team at UTHealth Houston.

23 Jan 2025

AGA releases updated guidelines on hepatitis B reactivation in patients on immunosuppressive drugs

The American Gastroenterological Association (AGA) has unveiled an updated clinical practice guideline in Gastroenterology addressing the prevention and management of hepatitis B virus reactivation (HBVr) in patients on immunosuppressive drugs.

23 Jan 2025

Penn researchers develop optimized framework for COVID-19 vaccination distribution

Engineering and medical researchers at Penn have developed a groundbreaking framework that can determine the best and most computationally optimized distribution strategy for COVID-19 vaccinations in any given community.

22 Jan 2025

New technique identifies SARS-CoV-2 in blood and other fluids with high sensitivity

22 Jan 2025

U.S. mosquito species show minimal risk of spreading Oropouche virus, study finds

US mosquito species exhibit minimal competence for transmitting Oropouche virus (OROV), with low infection and transmission rates across tested populations, suggesting limited potential for local outbreaks despite rising imported cases.

22 Jan 2025

APOBEC proteins linked to DNA repeat expansion in Huntington's disease

People genetically susceptible to Huntington's disease often see their movement, mood, and cognition decline slowly over time.

22 Jan 2025

Social interventions could lead to major drop in national HIV incidence

Researchers at the University of Massachusetts Amherst have quantified the impacts of a constellation of social factors on the spread of HIV.

22 Jan 2025

Innovative research links biometric data to mood prediction in shift workers

The CORONA virus pandemic also brought about a pandemic of mental illness. Approximately one billion people worldwide suffer from various psychiatric conditions. Korea is one of more serious cases, with approximately 1.8 million patients exhibiting depression and anxiety disorders, and the total number of patients with clinical mental diseases has increased by 37% in five years to approximately 4.65 million.

22 Jan 2025

Study sheds light on the dynamics of non-persistent HPV infections

Non-persistent human papillomavirus (HPV) infections are characterized by a sharp increase in viral load followed by a long plateau, according to a study published January 21st in the open-access journal PLOS Biology by Samuel Alizon of the National Centre for Scientific Research (CNRS), France, and colleagues.

21 Jan 2025