antigenic drift


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Related to antigenic drift: Original antigenic sin

drift

 [drift]
1. slow movement away from the normal or original position.
2. a chance variation, as in gene frequency from one generation to another; the smaller the population, the greater are the random variations.
antigenic drift relatively minor changes in the antigenic structure of a virus strain, probably resulting from natural selection of variants circulating among an immune or partially immune population. See also antigenic shift.
ulnar drift ulnar deviation.

an·ti·gen·ic drift

the process of "evolutionary" changes in the molecular structure of DNA/RNA in microorganisms during their passage from one host to another; it may result from recombination, deletion, or insertion of genes, point mutations or combinations of these events; it leads to alteration (usually slow and progressive) in the antigenic composition, and therefore in the immunologic responses of individual people and populations to exposure to the microorganism concerned; common with influenzavirus.

antigenic drift

Etymology: Gk, anti, against, genein, to produce; AS, drifan, drift
a gradual relatively minor change in the antigenicity of a virus, periodically producing a mutant antigen requiring new antibodies and vaccines to combat its effects. Compare antigenic shift.

an·ti·gen·ic drift

(an'ti-jen'ik drift)
The process of "evolutionary" changes in molecular structure of DNA/RNA in microorganisms during their passage from one host to another; it may be due to recombination, deletion, or insertion of genes, point mutations, or combinations of these events; it leads to alteration (usually slow and progressive) in the antigenic composition, and therefore in the immunologic responses of individual people and populations to exposure to the microorganism concerned.

antigenic drift

minor changes in the surface ANTIGENS of INFLUENZA VIRUS, resulting from MUTATION and subsequent selection by the immune system of human and animal populations. These changes occur slowly over periods of years. See IMMUNITY.

an·ti·gen·ic drift

(an'ti-jen'ik drift)
The process of "evolutionary" changes in molecular structure of DNA/RNA in microorganisms during their passage from one host to another; affecting the immunologic responses of people and populations to exposure to the microorganism concerned.

antigenic drift (an´tējen´ik),

n the ability of viruses to alter their genetic makeup, thereby creating mutant antigens and bypassing the antibody barrier of the host.

antigenic

having the properties of an antigen.

antigenic competition
the immune response to an antigen may be reduced if an unrelated antigen is administered simultaneously or shortly before. These may be between different molecules (intermolecular) or different determinants on the same molecule (intramolecular).
antigenic drift
point mutations in genes resulting in antigenic change. See also orthomyxoviridae.
antigenic mimicry
similarities between sequences found in microbial proteins and host proteins which may result in cross-reacting immune responses and autoimmune disease.
antigenic shift
genetic reassortment between two subtypes of a viral species resulting in a new subtype with completely different antigenicity. See also orthomyxoviridae.

drift

chance variation; in genetics, the random changes in gene frequencies in a population.

antigenic drift
see antigenic drift.
drift lambing
a strategy in which ewes which have lambed are periodically removed from a flock of lambing ewes by moving the unlambed ewes on to the next paddock or field.
References in periodicals archive ?
Mutations and antigenic drift should not allow influenza viruses, even H5N1, to escape FluCide-I," said Dr.
The New South Wales strain data received from the national influenza collaborating center indicated that most influenza B strains of both Yamagata and Victoria lineages from New South Wales in 2008 showed low reactivity to reference strains, suggesting antigenic drift.
Antigenic drift occurs when there are mutations in HA and NA viral surface proteins, leading to reduced efficacy of vaccines not precisely matched to these mutations.
The antibody titers to the A/canine/Miami/2005 isolate in equine, canine, and ferret serum were similar to those for the 2003 and 2004 canine isolates, which indicates that the amino acid substitutions in the isolates did not result in measurable antigenic drift.
In contrast, the efficacy of current inactivated vaccines depends greatly on the ability to mount a strong response to novel (strain-specific) determinants generated through antigenic drift and shift on HA and NA.
Sentinel unvaccinated birds are kept in each house to monitor for virus shedding, antigenic drift, or both.
If serially (and cryptically) transmitted in humans, antigenic drift should have led to many changes after 2 decades.
They probably also circulated continuously in humans, undergoing gradual antigenic drift and causing annual epidemics, until the 1950s.
No precedent existed for defining a pandemic strain or distinguishing antigenic shift (a complete change) from antigenic drift (point mutations resulting in accumulated amino acid changes).
Francis died in 1969 and did not live to know the full explanations for antigenic shift through reassortment of gene segments from 2 parent viruses or antigenic drift through mutation.
Because of the high degree of antigenic drift among circulating influenza strains over the course of a year, vaccine strains must be reformulated specifically for each influenza season.
Influenza viruses continue to undergo antigenic drift, which is mostly reflected in accumulating changes in the HA.