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 Vertical Transmission?

Jamestown Canyon Virus: An Emerging Arboviral Threat in Temperate Climates

Virus History

Are Viruses a Lifeform?

Virus Uses in Virology

What is a Viral Mutation?

What Are Giant Viruses?

Virus Classification

Virus Eradication, Extinction, and Elimination Explained

Virus Origins

Virus Microbiology

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Virus Infection in Other Species

What are Filoviruses?

Virus Purification Methods

Human Diseases Caused by Viruses

What is the Difference Between Bacteria and Viruses?

Antiviral Immunity and COVID-19

What are Viral Clades?

Latest Virus News and Research

Scientists design artificial protein structures using advanced AI tools

An international research team led by a Korean scientist has succeeded in designing large-scale protein structures that faithfully replicate the self-assembly principles found in naturally occurring viruses, using artificial intelligence (AI).

18 Jun 2026

Mental health problems common in encephalitis survivors, study finds

A major new study has found that mental health and behavioral changes such as depression, anxiety, and emotional instability are common in people who survive encephalitis - inflammation of the brain that can be caused by infection or autoimmune disease.

18 Jun 2026

WHO Issues Comprehensive Guidelines On Filovirus Disease, Including Ebola And Marburg Disease

As the Democratic Republic of the Congo is battling an Ebola disease outbreak caused by the Bundibugyo virus, the World Health Organization (WHO) has released its first comprehensive guidelines for the clinical management of filovirus disease which include all types of Ebola and Marburg viruses.

18 Jun 2026

Cerebral organoid model offers insights into the mechanisms of Ebola virus persistence

Following infection, Ebola virus can survive unnoticed in the human body for months or even years, hiding in areas with little immune surveillance like the central nervous system.

17 Jun 2026

Novel gene therapy appears to be safe for Friedreich ataxia cardiomyopathy

A new gene therapy appears to be safe in patients diagnosed with Friedreich ataxia cardiomyopathy, a progressive and fatal inherited cardiac disease, according to a phase 1 clinical trial led by Weill Cornell Medicine researchers.

17 Jun 2026

Targeted vaccination strategies strengthen global biosecurity and biosafety

Biosafety prevents biohazard risks to humans and the environment, biosecurity protects biological assets from misuse, and One Health is an interdisciplinary framework uniting human, animal, and environmental health—all core to global health protection.

17 Jun 2026

Synthetic biology platform unmasks hidden bacterial targets of bacteriophages

An interdisciplinary team of Rice University researchers has uncovered previously unknown relationships between bacteriophages - viruses that infect bacteria - and their bacterial hosts, offering a powerful new tool for next-generation microbiome engineering.

17 Jun 2026

Maternal RSV vaccine shows 68% protection against infant RSV hospitalization

In a test-negative case-control study of 274 hospitalized infants aged 90 days or younger, maternal RSVpreF vaccination was associated with 67.6% effectiveness against RSV-associated acute respiratory illness hospitalization. Protection was similar against RSV-linked lower respiratory tract disease, with the highest point estimate in the first month of life, although confidence intervals were wide.

16 Jun 2026

Semaglutide, omega-3s and diet shift epigenetic aging clocks in human studies

A systematic review identified 41 human studies evaluating interventions targeting next-generation DNA methylation-based aging clocks. Pharmaceutical, lifestyle, supplement, clinical, and psychosocial interventions shifted some clock outputs, but these biomarkers remain investigational rather than proven clinical surrogates.

16 Jun 2026

Tiny genetic change influences coronavirus spillover into humans

Most pandemics start when a pathogen spreads from animals to humans. It's a leading explanation for the COVID-19 pandemic: the SARS-CoV-2 virus, which causes COVID-19, is a cousin to coronaviruses that live in bats.

15 Jun 2026

Wastewater analysis offers novel approach to track HIV burden

Human immunodeficiency virus 1 (HIV-1) detection in wastewater offers a novel approach to monitor the virus in communities.

15 Jun 2026

Just ten viral particles can infect cows with bird flu

Just 10 viral particles of the H5N1 bird flu that caused hundreds of influenza outbreaks in U.S. dairy cattle can cause infection in cows, a new study shows.

15 Jun 2026

The importance of ketones from a clinical and medical perspective

In this interview, News-Medical talks to Marcin Pacek, senior director of medical and scientific affairs in Europe for Nova Biomedical, about the importance of ketones in a medical and clinical setting.

From Nova Biomedical 15 Jun 2026

New mRNA flu vaccine offers broader protection against influenza strains

A new study led by researchers at Washington University School of Medicine in St. Louis has found that an investigational mRNA influenza vaccine helps the immune system recognize a wider range of influenza viruses than today's standard flu shot, offering stronger and potentially longer-lasting protection.

15 Jun 2026

Trauma-related conditions drive deaths in women with HIV

Women with HIV most often die from preventable, trauma-related conditions like substance use and mental illness - not the virus itself. Yet, these leading causes are largely missing from official death records, according to new research by UC San Francisco.

12 Jun 2026

Renowned physician‑scientist to lead Houston Methodist's cell and gene therapy research

Malcolm Brenner, an internationally recognized physician‑scientist renowned for his leadership in cell and gene therapy, has been tapped to lead the newly formed Houston Methodist Center for Cell and Gene Therapy.

12 Jun 2026

Engineered phages use molecular anchors to enter human cells

The study identified phage surface proteins acting as molecular anchors. These proteins confer phages ith the ability to attach to human cells.

12 Jun 2026

Antibody profiles offer insights into long Covid cognitive symptoms

Persistent symptoms after COVID-19 infection continue to affect millions of people worldwide, even as the number of acute infections has declined.

12 Jun 2026

Leading AI models ace many vaccine questions but falter on clinical rules

A multilingual benchmark of 1,886 vaccine-related questions found that large language models answered most items accurately across English, Spanish, and Chinese. However, performance varied by vaccine type, language, and prompting method, with persistent errors in dosing, contraindications, age eligibility, and other clinically sensitive guidance.

11 Jun 2026

Single-dose vaccine provides complete protection against Andes hantavirus

In a study published in The Lancet, researchers at The University of Texas Medical Branch (UTMB) report the development of new vaccines that, in animal testing, provided full protection against the deadly Andes hantavirus after a single dose.

11 Jun 2026