1. Kilbourne ED. In¯uenza. New York: Plenum Medical
Book Co., 1987.
2. Potter CW. Inactivated in¯uenza virus vaccines. In:
Beare AS, ed. Basic and applied in¯uenza research.
Boca Raton: CRC Press, 1982: 119±58.
3. Webster RG, Bean WJ, Gorman OT, Chambers TM,
Kawaoka Y. Evolution and ecology of in¯uenza A
viruses. Microbiol Rev 1992; 56: 152±79.
4. Wilson IA, Cox NJ. Structural basis of immune
recognition of in¯uenza virus hemagglutinin. Ann Rev
Immunol 1990; 8: 737±71.
5. Archetti I, Horsfall FL. Persistent antigenic variation of
in¯uenza A viruses after incomplete neutralization in
ovo with heterologous immune serum. J Exp Med 1950;
92: 441±62.
6. Isaacs A. The 1951 in¯uenza virus. Proc R Soc Med
1951; 44: 801±3.
7. Laver WG, Webster RG. Selection of antigenic mutants
of in¯uenza viruses. Isolation and peptide mapping of
their hemagglutinating proteins. Virol 1968; 34:
193±202.
8. Fazekas de St Groth S. Antigenic, adaptive and
adsorbtive variants of the in¯uenza A hemagglutinin.
In: Laver WG, Bachmayer H, Weil R, eds. Topics in
infectious disease. Vol. 3. Vienna: Springer-Verlag,
1978: 25±48.
9. Hyslop NStG. Isolation of variant strains from footand-
mouth disease virus propagated in cell cultures
containing antiviral serum. J Gen Microbiol 1965; 41:
135±42.
10. Rojas ER, Carillo E, Schiappacassi M, Campos R.
Modi®cation of foot-and-mouth disease virus 01
Caseros after serial passages in the presence of antiviral
polyclonal sera. J Virol 1992; 66: 3368±72.
11. Reitz MS, Wilson C, Naugle C, Gallo RC, Robert-
Guroff M. Generation of a neutralization-resistant
variant of HIV-1 is due to selection for a point mutation
in the envelope gene. Cell 1988; 54: 57±63.
12. McKeating JA, Bennett J, Zolla-Pazner S, et al.
Resistance of a human serum-selected human immunode
®ciency virus type 1 to neutralization by CD4 binding
site monoclonal antibodies is conferred by a single
amino acid change in gp120. J Virol 1993; 67: 5216±25.
13. Hyslop NStG, Fagg RH. Isolation of variants during
passage of a strain of foot-and-mouth disease virus in
partly immunized cattle. J Hyg 1965; 63: 357±68.
14. Carman WF, Zanetti AR, Karayiannis P, et al. Vaccine
escape mutants of hepatitis B virus. Lancet 1990; 336:
325±9.
15. Harrison TJ, Oon CJ, Zuckerman AJ. A novel escape
variant (ala 144) of hepatitis B virus in an identical twin before selection in the mother. In: Nishioka K, Suzuki
H, Mishiro S, Oda T, eds. Viral hepatitis and liver
disease. Tokyo: Springer-Verlag, 1994: 248±51.
16. Albert J, Abrahamsson B, Nagy K, et al. Rapid
development of isolate-speci®c neutralizing antibodies
after primary HIV-1 infection and consequent emergence
of virus variants which resist neutralization by
autologous sera. AIDS 1990; 4: 107±12.
17. Arendrup M, So$ nnerborg A, Svennerholm B, et al.
Neutralizing antibody response during human immunode
®ciency virus type 1 infection : type and group
speci®city and viral escape. J Gen Virol 1993; 74:
855±63.
18. Nara PL, Smit L, Dunlop N, et al. Emergence of viruses
resistant to neutralization by V3-speci®c antibodies in
experimental human immunode®ciency virus type 1
IIIB infection of chimpanzees. J Virol 1990; 64:
3779±91.
19. Watkins BA, Reitz MS, Wilson CA, Aldrich K, Davis
AE, Robert-Guroff M. Immune escape by human
immunode®ciency virus type 1 from neutralizing antibodies:
evidence for multiple pathways. J Virol 1993;
67: 7493±500.
20. Lambkin R, McLain L, Jones SE, Aldridge SL,
Dimmock NJ, Neutralization escape mutants of type A
in¯uenza virus are readily selected by antiserum from
mice immunized with whole virus : a possible mechanism
for antigenic drift. J Gen Virol 1994; 75:
3493±502.
21. Lambkin R, Dimmock NJ. All rabbits immunized with
type A in¯uenza virions have a serum antibody
haemagglutination-inhibition antibody response biased
to a single epitope in antigenic site B. J Gen Virol 1995;
76: 889±97.
22. Lambkin R, Dimmock NJ. Longitudinal study of an
epitope-biased haemagglutination-inhibition antibody
response in rabbits immunized with type A in¯uenza
virus. Vaccine 1996; 14: 212±8.
23. Sugrue RJ, Bahadur G, Zambon MC, Hall-Smith M,
Douglas AR, Hay AJ. Speci®c structural alteration of
the in¯uenza haemagglutinin by amantadine. EMBO J
1990; 9: 3469±76.
24. Wiley DC, Wilson IA, Skehel JJ. Structural identifcication
of the antibody-binding sites of Hong Kong
in¯uenza haemagglutinin and their involvement in
antigenic variation. Nature 1981; 289: 373±8.
25. Roberts PC, Garten W, Klenk H-D. Role of conserved
glycosylation sites in maturation and transport of
in¯uenza A virus hemagglutinin. J Virol 1993; 67:
3048±60.
26. Smith CA, Barnett BC, Thomas DB, Temoltzin-
Palacios F. Structural assignments of novelandimmunodominant
antigenic sites in the neutralizing antibody
response of CBA}Ca mice to in¯uenza virus. J Exp
Med 1991; 173: 953±9.
27. Temoltzin-Palacios F, Thomas DB. Modulation of
immunodominant sites in in¯uenza hemagglutinin
compromise antigenic variation and select receptorbinding
variant viruses. J Immunol 1994; 179: 1719±24.
28. Patera AC, Graham CM, Thomas DB, Smith CA.
Immunodominance with progenitor B cell diversity in
the neutralizing antibody repertoire to in¯uenza infection.
Eur J Immunol 1995; 25: 1803±9.
29. Clarke SH, Staudt LM, Kavaler J, Schwartz D, Gerhard
WU, Weigert MG. V region gene usage and somatic
mutation in the primary and secondary responses to
in¯uenza virus hemagglutinin. J Immunol 1990; 144:
2795±801.
30. Haaheim LR. Haemagglutinin-inhibition antibodies in
human sera to an antigenic mutant of in¯uenza
A}Texas}1}77 (H3N2) virus obtained in vitro. Acta
Pathol Microbiol Immunol Scand B 1980; 88: 351±3.
31. Natali A, Oxford JS, Schild GC. Frequency of naturally
occurring antibody to in¯uenza virus antigenic variants
selected in vitro with monoclonal antibody. J Hyg 1981;
87: 185±90.
32. Oxford JS, Haaheim LR, Slepushkin A, Werner J,
Kuwert E, Schild GC. Strain speci®city of serum
antibody to the haemagglutinin of in¯uenza A (H3N2)
viruses in children following immunization or natural
infection. J Hyg 1981; 86: 17±26.
33. Wang M-L, Skehel JJ, Wiley DC. Comparative analyses
of the speci®cities of anti-in¯uenza hemagglutinin
antibodies in human sera. J Virol 1986; 57: 124±8.