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 a Viral Mutation?

What are Filoviruses?

What are Viral Clades?

Jamestown Canyon Virus: An Emerging Arboviral Threat in Temperate Climates

Virus Classification

Virus Eradication, Extinction, and Elimination Explained

Antiviral Immunity and COVID-19

Are Viruses a Lifeform?

What is the Difference Between Bacteria and Viruses?

Human Diseases Caused by Viruses

Virus Microbiology

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Virus Origins

Virus Infection in Other Species

Virus Uses in Virology

Virus Purification Methods

What is Vertical Transmission?

Virus History

What Are Giant Viruses?

Latest Virus News and Research

Genes and biological networks that drive long COVID risk

This study merges causal genetics and network theory, revealing 32 genes linked to long COVID, offering insights for diagnostics and personalized therapies.

19 Dec 2025

Inside the FDA’s vaccine uproar

Six days after a senior FDA official sent a sweeping internal email claiming that covid vaccines had caused the deaths of "at least 10 children," 12 former FDA commissioners released an extraordinary warning in the Dec. 3 issue of the New England Journal of Medicine.

19 Dec 2025

Phages use small RNA to hijack bacterial cells and boost replication

As antibiotic-resistant infections rise and are projected to cause up to 10 million deaths per year by 2050, scientists are looking to bacteriophages, viruses that infect bacteria, as an alternative.

18 Dec 2025

Whooping cough cases rise sharply across the United States

Pertussis, also known as whooping cough, is a vaccination-preventable illness that has been on the rise in the United States. Following a several-year lull during the pandemic, cases of whooping cough rose sixfold in 2024 and remain high.

18 Dec 2025

New nanoparticle vaccines show promise against multiple deadly filoviruses

Filoviruses get their name from the Latin word "filum," meaning thread-a reference to their long, filamentous shape. This virus family contains some of the most dangerous pathogens known to science, including Ebola, Sudan, Bundibugyo and Marburg viruses.

18 Dec 2025

Rapid HIV viral load testing shows mixed effects on seeking care

According to the U.S. Centers for Disease Control and Prevention (CDC) and other sources, there are approximately 1.2 million people living with HIV in the United States, and another 1.2 to 2.2 million who are at highest risk for infection and could benefit from the preventive measure known as HIV pre-exposure prophylaxis (PrEP).

18 Dec 2025

Social living allows genetic effects to spread through the gut microbiome

Your "roommate's" genes could be influencing the bacteria living in your gut, and vice versa, according to a study of rats published today in Nature Communications.

18 Dec 2025

Flu wave’s hidden cost on people with cystic fibrosis

People with cystic fibrosis (CF) are uniquely vulnerable to the flu wave currently ripping through the UK, a clinical researcher from The University of Manchester has warned.

18 Dec 2025

Researchers develop antibody to combat HCMV, a common, overlooked virus

Researchers at Texas Biologics have made an important discovery that could improve treatment of human cytomegalovirus (HCMV), a common but overlooked virus that poses serious risks to vulnerable populations, including people with compromised immune systems. According to the Centers for Disease Control and Prevention, the virus is the most infectious cause of birth defects in the United States.

18 Dec 2025

SARS-CoV-2 manipulates host cell's RNA to weaken the immune response

Researchers at the Federal University of São Paulo (UNIFESP) in Brazil have discovered that SARS-CoV-2, the virus that causes COVID-19, uses a sophisticated tactic to evade the human body's defense system.

17 Dec 2025

Hyperphosphorylated tau may help protect the brain from infection

One of the main proteins that contributes to Alzheimer's disease is called phospho-tau (p-tau). When p-tau gets too many phosphate groups attached to it (a process called hyperphosphorylation), it starts to stick together and form clumps called "tangles" inside of brain nerve cells.

17 Dec 2025

Targeted mRNA vaccines train the immune system to destroy cancer cells

No matter where cancer cells grow in the human body, they are a threat to our health and our lives. But instead of treating them with chemotherapy or radiation - which have undesirable side effects - what if we could train our own immune systems to kill the rogue cells?

16 Dec 2025

Traumatic brain injury disrupts brain drainage and accelerates Alzheimer’s risk

University of Virginia School of Medicine researchers have uncovered how and why traumatic brain injury (TBI) increases the risk for Alzheimer's disease, and their work suggests a potential way to prevent that increased risk.

16 Dec 2025

SARS-CoV-2 evolves after jumping from humans to zoo animals

Research on SARS-CoV-2 in zoo tigers, lions, and hyenas shows rapid viral evolution and adaptation, offering insights into cross-species transmission dynamics.

16 Dec 2025

Chemotherapy may reduce HIV-infected T cells

Advancements in HIV/AIDS research, drug development and clinical practice since the 1980s have made it possible for people living with HIV to lead long, productive lives and keep the virus in check at undetectable levels and nontransmissible as long as therapy is maintained.

15 Dec 2025