MIMG 102 Lecture Notes - Lecture 15: Antigenic Drift, Antigenic Shift, Reassortment

• School: UCLA
• Department: Microbiology, Immunology, and Molecular Genetics
• Course: MIMG 102
• Professor: Dasgupta Asim

Document Summary

Lecture 15 influenza ctd antigenic drift: slow accumulation of mutations; months - years, mutation on ha & na. Antigenic shift: fast, days - weeks, pseudorecombination (rna not cut), or reassortment. Polio can"t do antigenic shift because only 1 genome: feature of flu virus because of segmented. Ha & na new to immune system -> spreads fast. Also vaccine virus adapted to human & infects human very well (q: is new virus dangerous because of virulent hana or non-virulent adaptation?) Immediate change in antigenic properties: 2^8 = 256 possible new strains, new strain may be more fit than either parent and rapidly selected in the host. Influenza life cycle: wild birds as main reservoir of viruses (carries viruses but not sick); perennial reservoir infect domestic bird (respiratory illness) -> infect pigs; humans can also infect pigs. Animal-to-human passage/vice versa; zoonosis: the genes from avian, swine and human viruses can re- combine in the pig, producing a new virus (antigenic shift)