Search results
Results from the WOW.Com Content Network
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more
Specific acquired immunity against infectious diseases may be mediated by antibodies and/or T lymphocytes. Immunity mediated by these two factors may be manifested by: a direct effect upon a pathogen, such as antibody-initiated complement-dependent bacteriolysis, opsonoization, phagocytosis and killing, as occurs for some bacteria,
Adaptive (or acquired) immunity creates an immunological memory leading to an enhanced response to subsequent encounters with that same pathogen. This process of acquired immunity is the basis of vaccination. Dysfunction of the immune system can cause autoimmune diseases, inflammatory diseases and cancer.
An individual's immunity can be acquired via a natural infection or through artificial means, such as vaccination. [51] When a critical proportion of the population becomes immune, called the herd immunity threshold (HIT) or herd immunity level (HIL), the disease may no longer persist in the population, ceasing to be endemic .
Respiratory illness activity – a measure of how often conditions like the common cold, flu, COVID-19, and respiratory syncytial virus are diagnosed – is currently "high" in the United States ...
Immunity can be acquired either actively or passively. Immunity is acquired actively when a person is exposed to foreign substances and the immune system responds. Passive immunity is when antibodies are transferred from one host to another. Both actively acquired and passively acquired immunity can be obtained by natural or artificial means.
The CDC said the patient's sample showed mutations in the hemagglutinin (HA) gene, the part of the virus that plays a key role in it attaching to host cells. The mutations seen in the patient are ...
Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses.Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue.