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 ?
Comparison of influenza viruses (a) Characteristic Influenza A Influenza B Genome Negative-strand RNA, Negative-strand RNA, eight segmented genes eight segmented genes Sequence High Moderate variability in HA and NA Mode of antigen Antigenic drift and Antigenic drift only variation antigenic shift Hosts Humans, avian, swine, Humans only equine, marine mammals Epidemiology Epidemic, pandemic Epidemic, nonpandemic (a) RNA, ribonucleic acid; HA, hemagglutinin; NA, neuraminadase.
Vaccines may be ineffective in the field due to the antigenic drift caused by the observed rapid mutation rate of the influenza virus, according to these physicians.
Mutation from arginine to lysine at the position 189 of hemagglutinin contributes to the antigenic drift in H3N2 swine influenza viruses.
Compound this with an antigenic drift, after which parents become convinced the injectable flu vaccine does not work very well (only some semblance of truth).
Antigenic drift and changes in vaccine composition, 1987-89.
We found no evidence of substantial antigenic drift in circulating viruses that could affect seroepidemiology results (online Technical Appendix Table).
One dose lasts a full season and (I speculate) possibly several seasons if the antigenic drift is not too far.
The genetic makeup of influenza viruses allows frequent minor genetic changes, known as antigenic drift, and these changes require annual reformulation of influenza vaccines.
The recent increase in scarlet fever notifications might be attributable to antigenic drift, increase in virulence of GAS (8), or increased circulation of GAS.
In 2004, further antigenic drift occurred away from this vaccine strain (30) which may explain the continuing increased mortality in 2004, despite the apparently low level of influenza circulation generally.
Additionally, major antigenic drift among influenza viruses (H1N1 to H2N2 to H3N2 from 1918 to 1969) can be temporally mapped to above-ground nuclear testing in the flight paths of migratory birds across Siberia to Eastern China.