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

Alarming spread of H5N1 bird flu in US dairy cattle reveals cross-species transmission dangers

Researchers discovered that the H5N1 avian influenza virus has spilled over into dairy cattle in the US, posing significant cross-species transmission risks. Their multidisciplinary study reveals the virus's evolution and its zoonotic potential, emphasizing the need for heightened biosecurity measures.

25 Jul 2024

COVID pandemic accelerated brain aging, especially in males and deprived groups

The COVID-19 pandemic accelerated brain aging, particularly in males and those from deprived backgrounds, with significant cognitive performance decline in infected individuals. This impact was observed regardless of COVID-19 infection status, highlighting the role of psychosocial stressors.

25 Jul 2024

Experimental cancer drug may help clear HIV from infected cells in the brain

An experimental drug originally developed to treat cancer may help clear HIV from infected cells in the brain, according to a new Tulane University study.

25 Jul 2024

Recombinant shingles vaccination found to lower dementia risk

The effects of recombinant shingles vaccines on dementia.

25 Jul 2024

Study identifies genes increasing risk of severe COVID-19

Whether or not a person becomes seriously ill with COVID-19 depends, among other things, on genetic factors. With this in mind, researchers from the University Hospital Bonn (UKB) and the University of Bonn, in cooperation with other research teams from Germany, the Netherlands, Spain and Italy, investigated a particularly large group of affected individuals.

25 Jul 2024

$Study shows wearable health sensors only prompt a fraction of at-home tests$

Study shows wearable health sensors only prompt a fraction of at-home tests

When seemingly healthy people receive an alert from a wearable sensor telling them they might have a respiratory virus-;based on small changes in their unique heartrate, sleep and activity patterns-;what do they do? According to a new study by Scripps Research scientists carried out at the height of the COVID-19 pandemic, only a quarter of people follow up such an alert with an at-home viral test.

24 Jul 2024

Breakthrough gene therapy restores dystrophin protein in Duchenne muscular dystrophy

Indiana University School of Medicine researchers have made a significant breakthrough in developing a new gene therapy approach that restores full-length dystrophin protein, which could lead to new treatments for people with Duchenne muscular dystrophy (DMD).

24 Jul 2024

Proof-of-concept animal studies demonstrate a step forward in the fight against HIV

Researchers in George Mason University's Center for Infectious Disease Research (CIDR) and Tulane National Primate Research Center conducted a breakthrough proof-of-concept study in Nature's Gene Therapy that found an HIV-like virus particle that could cease the need for lifelong medications.

24 Jul 2024

New study helps better understand the pathology of fatty liver disease MASH

A new study brings researchers closer to better understanding the pathology of the fatty liver disease MASH, which stands for metabolic dysfunction-associated steatohepatitis.

24 Jul 2024

Ohio State leads multi-million dollar research on long COVID solutions

A 2022 study suggesting that blocking a single molecule could protect against severe illness in COVID-19 has led to a $15 million federal grant supporting a comprehensive effort to learn more – with finding a solution to long COVID at the center of the new research.

23 Jul 2024

Reliability of HIV viral load tests for CAB-LA PrEP questioned in new study

A single laboratory-based HIV viral load test used by U.S. clinicians who provide people with long-acting, injectable cabotegravir (CAB-LA) HIV pre-exposure prophylaxis (PrEP) did not reliably detect HIV in a multi-country study.

23 Jul 2024

More types of lung cells can be infected by SARS-CoV-2 than previously thought, scientists report

Scientists at Sanford Burnham Prebys, University of California San Diego and their international collaborators have reported that more types of lung cells can be infected by SARS-CoV-2 than previously thought, including those without known viral receptors.

23 Jul 2024

Abacavir linked to increased cardiovascular risk in HIV patients, study finds

CJ Fichtenbaum et al. Abacavir is associated with elevated risk for cardiovascular events in the REPRIEVE trial. International AIDS Conference. Friday, July 26, 2024

23 Jul 2024

Long-acting injectable CAB-LA safe for HIV PrEP during pregnancy, study finds

Long-acting injectable cabotegravir (CAB-LA) was safe and well tolerated as HIV pre-exposure prophylaxis (PrEP) before and during pregnancy in the follow-up phase of a global study among cisgender women.

23 Jul 2024

Evaluation and treatment of early Lyme disease

Every year in the United States, an estimated 476,000 people are diagnosed and treated for Lyme disease. The estimate comes from the U.S. Centers for Disease Control and Prevention (CDC).

23 Jul 2024

PrEPVacc HIV vaccine trial shows no reduction in infections

The results of the PrEPVacc HIV vaccine trial conducted in Eastern and Southern Africa, which ran between 2020 and 2024, show conclusively that neither of the two experimental vaccine regimens tested reduced HIV infections among the study population.

23 Jul 2024

New method can rapidly determine virus infectivity

A new method that can rapidly determine whether a virus is infectious or non-infectious could revolutionize the response to future pandemics.

23 Jul 2024

‘A catalyst for revolution’: Launch of Thrive looks to safeguard public health

Brisbane is positioned to become the global hub for healthy buildings with today's launch of the ARC Training Centre for Advanced Building Systems against Airborne Infection Transmission (Thrive).

23 Jul 2024

COVID-19's impact on maternal mortality demands rethink of public health strategies

During the peak of the SARS-CoV-2 pandemic, there was an increase in maternal mortality in Chile. This is confirmed by a natural population experiment based on data from the Department of Health Statistics and Information (DEIS) of the Chilean Ministry of Health. The research was published in PLOS Global Public Health.

23 Jul 2024

Researchers discover new target for treating diseases linked to T-cell leukemia virus type 1

A team of researchers from Penn State College of Medicine found a new target for treating diseases associated with human T-cell leukemia virus type 1 (HTLV-1).

22 Jul 2024