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

See more featured articles »

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

NIH funds new research to combat emerging viruses

Albert Einstein College of Medicine has received a five-year, $14 million per year grant from the National Institute of Allergy and Infectious Diseases (NIAID) to participate in a broad national effort to develop "plug-and-play" vaccines and antibody-based therapies against a wide range of emerging viruses. The grant is part of NIAID's new Research and Development of Vaccines and Monoclonal Antibodies for Pandemic Preparedness (ReVAMPP) Network, which was announced earlier today.

14 Sep 2024

New research network focuses on high-priority viruses

The National Institutes of Health (NIH) has established a pandemic preparedness research network to conduct research on high-priority pathogens most likely to threaten human health with the goal of developing effective vaccines and monoclonal antibodies. Currently, many of the diseases caused by these pathogens have no available vaccines or therapeutics, and investing in this research is key to preparing for potential public health crises-;both in the United States and around the world. NIH's National Institute of Allergy and Infectious Diseases (NIAID) expects to commit approximately $100 million per year to fund the program, pending the availability of funds.

14 Sep 2024

Scientists develop selective therapy for tau tangles

Scientists have developed new potential therapies that selectively remove aggregated tau proteins, which are associated with Alzheimer's disease, and improve symptoms of neurodegeneration in mice.

14 Sep 2024

New insight into the causes of autoimmune diseases

Autoimmune diseases are widespread and notoriously difficult to treat. In part, this is because why the immune system attacks its own tissues in patients with these conditions remains poorly understood.

14 Sep 2024

Study reveals how SARS-CoV-2 triggers diabetes by destroying pancreatic cells

Researchers from Weill Cornell Medicine have used a cutting-edge model system to uncover the mechanism by which SARS-CoV-2, the virus that causes COVID-19, induces new cases of diabetes, and worsens complications in people who already have it.

13 Sep 2024

National survey reveals vaccine hesitancy ahead of flu and COVID-19 season

With flu season just around the corner and COVID-19 cases on the rise, a new nationwide survey from The Ohio State University Wexner Medical Center reveals hesitancy around vaccines this fall.

13 Sep 2024

WHO adds MVA-BN vaccine to prequalification list as first vaccine against mpox

The World Health Organization (WHO) has announced the MVA-BN vaccine as the first vaccine against mpox to be added to its prequalification list.

13 Sep 2024

Researchers find no evidence of monkeypox infection in pets, despite presence of viral DNA

Study found that MPXV DNA on pets in mpox-affected households was likely due to human contamination, not true infection, as no live virus or antibodies were detected.

12 Sep 2024

COVID-19 vaccines prevented millions of deaths across Latin America and the Caribbean, study shows

Researchers estimate that COVID-19 vaccines averted between 610,000 and 2.62 million deaths in select Latin American and Caribbean countries from early 2021 to May 2022.

12 Sep 2024

New vaccine candidate shows promise for protecting against Lassa fever

Researchers from Thomas Jefferson University and the University of Maryland Baltimore, in collaboration with the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) and the Geneva Foundation, have developed a promising new vaccine candidate that protects against Lassa fever.

12 Sep 2024

Avian influenza detected in Texas wastewater samples

Avian influenza A(H5N1) virus, which spread to cattle and infected 14 people this year, was detected using virome sequencing in the wastewater of 10 Texas cities by researchers at UTHealth Houston and Baylor College of Medicine.

12 Sep 2024

COVID-19 reduces male fertility by affecting semen quality and hormone levels

Study reveals that SARS-CoV-2 significantly impairs male fertility by reducing semen quality and altering reproductive hormone levels, with partial recovery post-treatment.

11 Sep 2024

Single dose of MVA-BN vaccine shows 58% effectiveness against mpox

A single dose of the Modified vaccinia Ankara-Bavarian Nordic (MVA-BN) was 58% effective in protecting again mpox infection, according to a new study published in BMJ.

11 Sep 2024

New acoustic tweezers isolate viruses from saliva with high precision

Developing antiviral therapeutics and vaccines requires close study of the viruses that cause disease. But how can these small germs be isolated from complex biological samples like saliva?

11 Sep 2024

Promising new approach to combat HIV

Researchers at Université de Montréal's affiliated hospital research center, the CRCHUM, say the discovery could help lessen and even eliminate viral loads in people undergoing antiretroviral therapy.

11 Sep 2024

COVID-19 lockdowns accelerated brain aging in adolescent girls, researchers find

Researchers discovered that COVID-19 lockdowns accelerated cortical thinning in adolescent brains, with females experiencing more significant and widespread changes than males, indicating a higher developmental impact on female brains.

10 Sep 2024

Gene therapy improves vision in patients with Bothnia dystrophy

Bothnia dystrophy is a form of hereditary blindness, prevalent in the region Västerbotten in Sweden. A new study at Karolinska Institutet published in Nature Communications shows that gene therapy can improve vision in patients with the disease.

10 Sep 2024

Targeted RSV vaccination for older adults with health conditions found cost-effective

Targeting vaccination programs for respiratory syncytial virus (RSV) to older adults with underlying health conditions is a cost-effective way to reduce disease, according to a new modelling study https://www.cmaj.ca/lookup/doi/10.1503/cmaj.240452 in CMAJ.

9 Sep 2024

SP-101 gene therapy shows promise for cystic fibrosis treatment

Scientists from Spirovant Sciences describe SP-101, a novel adeno-associated virus (AAV) gene therapy for the treatment of cystic fibrosis (CF) in the peer-reviewed journal Human Gene Therapy.

9 Sep 2024

Eating fruit, oats and rye in childhood may increase type 1 diabetes risk

New research being presented at the annual meeting of the European Association for the Study of Diabetes (EASD) in Madrid, Spain (9-13 September), shows that eating fruit, oats and rye in childhood is associated with a higher risk of developing type 1 diabetes (T1D).

9 Sep 2024