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

WHO expands Emergency Use Listing for mpox diagnostics

As part of ongoing efforts to enhance quality-assured testing options, the World Health Organization (WHO) has listed two additional mpox in vitro diagnostics under its Emergency Use Listing (EUL) procedure.

30 Oct 2024

New toolkit aims to help U.S. hospitals spot deadly viral hemorrhagic fevers faster and safer

Researchers develop a laboratory toolkit to assist frontline healthcare facilities or the care of patients with suspected viral hemorrhagic fevers.

30 Oct 2024

Research identifies respiratory transmission potential of H5N1 virus

A highly pathogenic avian influenza (HPAI) H5N1 virus, isolated from the eye of a farm worker who became infected through contact with dairy cows, was lethal in mice and ferrets infected in a high-containment laboratory environment, according to a new study in Nature.

28 Oct 2024

Study highlights importance of RSV vaccination for high-risk populations

Since their introduction last year, researchers have been monitoring the real-world impact of the new respiratory syncytial virus (RSV) vaccines.

28 Oct 2024

Novel gene therapy PS-002 targets podocytes in IgA nephropathy

IgA nephropathy is an autoimmune kidney disease, and complement, a component of the innate immune system, plays a role in the condition's pathogenesis.

27 Oct 2024

Tenofovir amibufenamide does not alter lipid levels in patients with chronic hepatitis B

The effect of tenofovir amibufenamide (TMF) on blood lipid profiles in patients with chronic hepatitis B (CHB) remains unclear. This study aimed to explore whether TMF affects blood lipids during 48 weeks in patients with CHB.

26 Oct 2024

Diagnostic toolkit aims to improve response to Marburg virus cases

Viral hemorrhagic fevers (VHF) such as Marburg virus disease have been in the news recently, with more than 60 cases of Marburg confirmed in Rwanda.

26 Oct 2024

Study: High prevalence of depression found among people living with HIV in Nigeria

Depression can lead to poor outcomes during antiretroviral therapy, and current evidence suggests high rates of depression among people living with human immunodeficiency virus (PLHIV), especially in low-and middle-income countries.

25 Oct 2024

Evaluating the effectiveness of GAAD for early detection of hepatocellular carcinoma

Early detection of hepatocellular carcinoma (HCC) is crucial for improving survival in patients with chronic hepatitis.

25 Oct 2024

Exclusive: Emails reveal how health departments struggle to track human cases of bird flu

Bird flu cases have more than doubled in the country within a few weeks, but researchers can't determine why the spike is happening because surveillance for human infections has been patchy for seven months.

25 Oct 2024

Masks and smart seating cut COVID-19 risks on flights, review finds

Air travel review reveals sporadic SARS-CoV-2 transmission, with mask use and seating proximity key to infection risk.

24 Oct 2024

High-sensitivity wastewater surveillance correlates with COVID-19 infections

Wastewater surveillance has gained attention as an effective method for monitoring regional infection trends. In July 2024, the National Action Plan for Novel Influenza, etc. included the regular implementation of wastewater surveillance during normal times, with results to be published periodically in Japan.

24 Oct 2024

Repeated mRNA vaccinations enhance mucosal antibody production

During the COVID pandemic, many of us have received multiple mRNA vaccines. New work by researchers at the VIB-UGent Center for Inflammation Research, Ghent University, and University Hospital Ghent, among others, has found that such repeated vaccinations lead to the presence of mucosal antibodies, for example, inside the nose. Their work appears in Science Translational Medicine.

23 Oct 2024

New antibody platform targets evolving viruses

Scientists at the Icahn School of Medicine at Mount Sinai, in collaboration with colleagues in the field, have developed an innovative antibody platform aimed at tackling one of the greatest challenges in treating rapidly evolving viruses like SARS-CoV-2: their ability to mutate and evade existing vaccines and therapies.

23 Oct 2024

Vaccination of young children could dramatically reduce mpox deaths in DRC

Vaccinating children under five-years-old in endemic mpox regions in the Democratic Republic of the Congo (DRC) would significantly reduce the number of deaths in the country, according to a new analysis by researchers at the Yale School of Public Health.

22 Oct 2024

Floor swabbing offers new insights for COVID-19 monitoring

COVID-19 is here to stay. As restrictions and human testing have waned, new research is tackling the challenge of how we can monitor, predict, and prevent cases and outbreaks of COVID-19, especially among vulnerable groups like hospitalized patients.

22 Oct 2024

New research uncovers how coronavirus evades immune defense

The novel coronavirus SARS-CoV-2 has an enzyme that can counteract a cell's innate defense mechanism against viruses, explaining why it is more infectious than the previous SARS and MERS-causing viruses.

22 Oct 2024

New single-chain mRNA vaccines offer enhanced immunity and protection against mpox

Study reveals single-chain mRNA vaccines confer 100% protection against lethal mpox challenge in mice, marking a significant advancement in vaccine technology.

22 Oct 2024

Sweden exceeds UNAIDS HIV goals but faces new challenges

Sweden has surpassed the UNAIDS 95-95-95 targets, with reduced HIV incidence and a steady increase in diagnosed and treated cases. However, challenges remain, especially among migrant populations and recent arrivals.

20 Oct 2024

Long-term low-dose antiviral treatment reduces eye disease risk from shingles

Long-term, low-dose antiviral treatment reduces the risk for potentially vision-damaging bouts of inflammation and infection, as well as pain, which occur when shingles affects the eye, according to new research presented October 19 at the annual meeting of the American Academy of Ophthalmology (AAO) in Chicago.

20 Oct 2024