TY - JOUR
T1 - Influenza drift and epidemic size
T2 - The race between generating and escaping immunity
AU - Boni, Maciej F.
AU - Gog, Julia R.
AU - Andreasen, Viggo
AU - Christiansen, Freddy B.
N1 - Funding Information:
This work was supported in part by NIH grant 1 RO1 GM607929, NIH grant GM28016 to Marcus W. Feldman, and the Danish Natural Science Research Council grant 51-00-0392. JRG is supported by Queens’ College, Cambridge, UK. Maciej F. Boni would like to express his sincere gratitude to the Danish-American Fulbright commission who helped fund and encourage this research.
PY - 2004/3
Y1 - 2004/3
N2 - Influenza in humans is characterised by strongly annual dynamics and antigenic evolution leading to partial escape from prior host immunity. The variability of new epidemic strains depends on the amount of virus currently circulating. In this paper, the amount of antigenic variation produced each year is dependent on the epidemic size. Our model reduces to a one-dimensional map and a full mathematical analysis is presented. This simple system suggests some basic principles which may be more generally applicable. In particular, for diseases with antigenic drift, vaccination may be doubly beneficial. Not only does it protect the population through classical herd immunity, but the overall case reduction reduces the chance of new variants being produced; hence, subsequent epidemics may be milder as a result of this positive feedback. Also, a disease with a high innate rate of antigenic variation will always be able to invade a susceptible population, whereas a disease with less potential for variation may require several introduction events to become endemic.
AB - Influenza in humans is characterised by strongly annual dynamics and antigenic evolution leading to partial escape from prior host immunity. The variability of new epidemic strains depends on the amount of virus currently circulating. In this paper, the amount of antigenic variation produced each year is dependent on the epidemic size. Our model reduces to a one-dimensional map and a full mathematical analysis is presented. This simple system suggests some basic principles which may be more generally applicable. In particular, for diseases with antigenic drift, vaccination may be doubly beneficial. Not only does it protect the population through classical herd immunity, but the overall case reduction reduces the chance of new variants being produced; hence, subsequent epidemics may be milder as a result of this positive feedback. Also, a disease with a high innate rate of antigenic variation will always be able to invade a susceptible population, whereas a disease with less potential for variation may require several introduction events to become endemic.
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U2 - 10.1016/j.tpb.2003.10.002
DO - 10.1016/j.tpb.2003.10.002
M3 - Article
C2 - 14766191
AN - SCOPUS:1242299532
SN - 0040-5809
VL - 65
SP - 179
EP - 191
JO - Theoretical Population Biology
JF - Theoretical Population Biology
IS - 2
ER -