Search results
Results from the WOW.Com Content Network
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. [1] Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. [2] [3] Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.
The study of viruses and virus-like agents, which seeks to understand and explain their structure, classification, evolution, and mechanisms of infection, as well as the diseases they cause, techniques to isolate and culture them, and their use in research and therapy. Virology is often considered a subfield of microbiology or of medical science.
A virus with this "viral envelope" uses it—along with specific receptors—to enter a new host cell. Viruses vary in shape from the simple helical and icosahedral to more complex structures. Viruses range in size from 20 to 300 nanometres; it would take 33,000 to 500,000 of them, side by side, to stretch to 1 centimetre (0.4 in).
Gamma phage, an example of virus particles (visualised by electron microscopy) Virology is the scientific study of biological viruses.It is a subfield of microbiology that focuses on their detection, structure, classification and evolution, their methods of infection and exploitation of host cells for reproduction, their interaction with host organism physiology and immunity, the diseases they ...
A viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells. [ 1 ] Examples are the common cold , gastroenteritis , corona , flu , pneumonia .
The vaccine is highly effective, a recent CDC report showed. Fully vaccinated people became infected in less than 1% of cases. And for those who did, infections were milder compared to ...
There are some viruses that can maintain a persistent infection by infecting different cells of the body. Some viruses once acquired never leave the body. A typical example is the herpes virus, which tends to hide in nerves and become reactivated when specific circumstances arise. [25]
The presence of the virus in Massachusetts this year was confirmed last month in a mosquito sample, and has been found in other mosquitoes across the state since then. In a 2019 outbreak, there ...