Change in the surface ANTIGEN of a microorganism. There are two different types. One is a phenomenon, especially associated with INFLUENZA VIRUSES, where they undergo spontaneous variation both as slow antigenic drift and sudden emergence of new strains (antigenic shift). The second type is when certain PARASITES, especially trypanosomes, PLASMODIUM, and BORRELIA, survive the immune response of the host by changing the surface coat (antigen switching). (From Herbert et al., The Dictionary of Immunology, 4th ed)

Descriptor ID	D000940
MeSH Number(s)	G05.365.073 G12.500.249
Concept/Terms	Antigenic Variation Antigenic Variation Antigenic Variability Variability, Antigenic Variation, Antigenic Antigen Variation Variation, Antigen Antigenic Diversity Antigenic Diversity Diversity, Antigenic Antigen Switching Antigen Switching Switching, Antigen Switching, Antigenic Antigenic Switching

Below are MeSH descriptors whose meaning is more general than "Antigenic Variation".

Below are MeSH descriptors whose meaning is related to "Antigenic Variation".

Below are MeSH descriptors whose meaning is more specific than "Antigenic Variation".