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

100-year-old BCG vaccine protects individuals with type 1 diabetes from infectious diseases

In new research, investigators at Massachusetts General Hospital (MGH) show that the 100-year-old Bacillus Calmette-Guérin (BCG) vaccine, originally developed to prevent tuberculosis, protects individuals with type 1 diabetes from severe COVID-19 disease and other infectious diseases.

22 May 2024

Biological similarities found between "chemo brain" and brain fog after COVID-19

Brain fog after COVID-19 is biologically similar to cognitive impairment caused by cancer chemotherapy, something doctors often refer to as "chemo brain."

22 May 2024

4 ways vaccine skeptics mislead you on measles and more

Measles is on the rise in the United States. So far this year, the number of cases is about 17 times what it was, on average, during the same period in each of the four years before, according to the Centers for Disease Control and Prevention.

22 May 2024

Health experts call for tighter biosecurity measures to monitor avian influenza

Health experts are calling for tighter biosecurity measures in global poultry production, from farms to markets, to monitor bird flu (avian influenza) following its spread among 888 cases of human infection with the avian influenza virus, also known as H5N1, have been reported from 23 countries, of which 463 were fatal, according to the World Health Organization (WHO).

21 May 2024

New drug-like molecules show promise in preventing influenza by blocking virus entry

Currently available flu medications only target the virus after it has already established an infection, but what if a drug could prevent infection in the first place?

21 May 2024

New tool may help identify newborns at highest risk for developing RSV lower respiratory tract infection

On the heels of a shortage of nirsevimab for infant respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) prevention, a new tool may help identify newborns at highest risk for developing serious RSV LRTI, according to research published at the ATS 2024 International Conference.

21 May 2024

New discovery could lead to a treatment for visceral leishmaniasis

A discovery by Simona Stäger's team could help come up with a treatment to the most serious form of leishmaniasis.

21 May 2024

New Health Blueprint for Southwest Virginia highlights grave health challenges

A sweeping new Health Blueprint for Southwest Virginia highlights the grave health challenges that grip the rural region but also proposes solutions to help residents live longer, healthier lives.

20 May 2024

LVRNA009 mRNA vaccine shows long-term efficacy against SARS-CoV-2 variants

Announcing a new article publication for Zoonoses journal. The global coronavirus disease 2019 (COVID-19) pandemic was caused by SARS-CoV-2.

20 May 2024

Newsom boosted California’s public health budget during covid. Now he wants to cut it.

When a doctor in Pasadena, California, reported in October that a hospital patient was exhibiting classic symptoms of dengue fever, such as vomiting, a rash, and bone and joint pain, local disease investigators snapped into action.

20 May 2024

New dengue vaccine TAK-003 gains WHO prequalification for high-burden areas

A new vaccine for dengue received prequalification from the World Health Organization (WHO) on 10 May 2024. TAK-003 is the second dengue vaccine to be prequalified by WHO. Developed by Takeda, it is a live-attenuated vaccine containing weakened versions of the four serotypes of the virus that cause dengue.

20 May 2024

Breakthroughs in germline-targeting HIV vaccine design for broad protection

Scientists have made several advances in the design of a class of HIV vaccines that could offer broad protection against the virus, according to four new research papers published this week in Science, Science Translational Medicine, and Science Immunology.

17 May 2024