Search results
Results from the WOW.Com Content Network
Viral pathogenesis is the study of the process and mechanisms by which viruses cause diseases in their target hosts, often at the cellular or molecular level. It is a specialized field of study in virology .
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 include the common cold , gastroenteritis , COVID-19 , the flu , and rabies .
A variety of prevention and treatment options exist for some viral pathogens. Vaccines are one common and effective preventive measure against a variety of viral pathogens. [45] Vaccines prime the immune system of the host, so that when the potential host encounters the virus in the wild, the immune system can defend against infection quickly.
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. [1] An infectious disease, also known as a transmissible disease or communicable disease, is an illness resulting from an infection.
A human pathogen is a pathogen (microbe or microorganism such as a virus, bacterium, prion, or fungus) that causes disease in humans. The human physiological defense against common pathogens (such as Pneumocystis ) is mainly the responsibility of the immune system with help by some of the body's normal microbiota .
The viral genome is then known as a "provirus" or, in the case of bacteriophages a "prophage". [13]: 836 Whenever the host divides, the viral genome is also replicated. The viral genome is mostly silent within the host. At some point, the provirus or prophage may give rise to the active virus, which may lyse the host cells.
The human virome is far from being completely explored and new viruses are discovered frequently. Unlike the roughly 40 trillion bacteria in a typical human microbiome, [8] an estimate of the number of viral particles in a healthy adult human is not yet available, although virions generally outnumber individual bacteria 10:1 in nature. [9]
Viral infections can cause disease in humans, animals and plants. In healthy humans and animals, infections are usually eliminated by the immune system, which can provide lifetime immunity to the host for that virus. Antibiotics, which work against bacteria, have no impact, but antiviral drugs can treat life-threatening infections. Those ...