Sep 17, 2024 · One way flu viruses change is called "antigenic drift." Drift consists of small changes (or mutations) in the genes of influenza viruses that can lead to changes in the surface proteins of the virus, HA (hemagglutinin) and NA (neuraminidase).

Antigenic shift is the process by which two or more different strains of a virus, or strains of two or more different viruses, combine to form a new subtype having a mixture of the surface antigens of the two or more original strains.

Sep 9, 2024 · Another type of change is called "antigenic shift." Shift is an abrupt, major change in an influenza A virus, resulting in new HA and/or new HA and NA proteins in influenza viruses that infect humans.

Antigenic shift, genetic alteration occurring in an infectious agent that causes a dramatic change in a protein called an antigen, which stimulates the production of antibodies by the immune systems of humans and other animals.

Sep 17, 2024 · Antigenic characterization refers to the analysis of antigenic properties of viruses to examine their relatedness. CDC antigenically characterizes viruses to monitor for changes in circulating viruses and to compare how similar these viruses are to those included in flu vaccines.

Antigenic shift is a major antigenic change that occurs when an influenza A virus that bears a novel HA (or novel HA and NA) antigenically distinct from that of previously circulating influenza A viruses appears in the human population.

Jan 7, 2022 · Antigenic shift refers to the gene recombination occurring when influenza viruses re-assort. Mutations causing minute changes in the hemagglutinin and neuraminidase antigens on the surface of the Influenza virus is termed antigenic drift.

Antigenic drift refers to slow, ongoing mutations that result in seasonal fluctuations in the flu, whereas antigenic shift refers to abrupt, significant changes that have the potential to trigger pandemics.

Mar 4, 2014 · Antigenic shift. Of greater public health concern is the process of antigenic shift – also called reassortment – through which at least two different viruses combine, resulting in exchange of the HA (for example H3 replaced by H5) and …

Antigenic shift involves major antigenic changes and it occurs through the introduction, in a new human virus, of immunologically distinct HA and/or NA molecules. Antigenic shift leads to high infection rates in an immunologically naïve population and is the cause of influenza pandemics.