Experts group viruses into categories — like family and genus — based on similar features, like size, shape and the type of genetic material they carry. Some common types of viruses that …

Many viruses spread in the air by coughing and sneezing, including influenza viruses, SARS-CoV-2, chickenpox, smallpox, and measles. Norovirus and rotavirus, common causes of viral …

Single-strand RNA viruses are further divided into those with positive-sense and negative-sense RNA. Positive-sense RNA viruses possess a single-stranded RNA genome that can serve as …

Classification of viruses can be approached through their morphology or the structure and replication strategy of their genomes, leading to the Baltimore classification system, which …

In this series, we’ll explore the basics of virology and demystify the complexities of the science. An important part of understanding virology is knowing that there are different types of viruses.

Virus are extremely tiny, even tinier than bacteria, so how do scientists study them? Hannah Gavin, a microbiologist at Harvard, shows us how she does just that in this video.

Dec 17, 2025 · Virus, infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. Viruses possess unique infective properties and …

Sep 26, 2025 · Influenza virus basics Influenza A viruses are the only influenza viruses known to cause flu pandemics (i.e., global epidemics of flu disease). A pandemic can occur when a new …

Jul 2, 2025 · Discover everything about viruses in this comprehensive guide: What is a virus, its unique structure and composition, classification types, and the viral life cycle.

Viruses are categorized based upon their type of nucleic acid (DNA viruses in yellow boxes and RNA viruses in blue boxes) and further classified based upon distinguishing characteristics.