Evaluation of live, cold-adapted influenza A and B virus vaccines in elderly and high-risk subjects.
We have evaluated the use of live cold-adapted influenza A and B virus vaccines in the elderly. Cold-adapted influenza A and B virus vaccines are safe and modestly immunogenic in individuals over 65 years of age. However, our studies and those of other groups have shown that immune response to cold-adapted vaccines in this age group are modest. Administration of combined cold-adapted influenza A and inactivated influenza vaccine has resulted in slightly higher frequencies of local and systemic humoral immune responses than inactivated vaccine alone in some, but not all, studies. In a double-blind field trial conducted in nursing homes over a 3 year period, combined cold-adapted influenza A (H3N2) and trivalent inactivated influenza vaccine resulted in a 60% decrease (95% CI, 18-82%) in the rate of laboratory documented influenza A compared with inactivated vaccine alone. Further studies of multivalent cold-adapted influenza vaccines used in combination with inactivated vaccine should be performed.
Treanor
J J
JJ
University of Rochester, Infectious Diseases Unit, NY 14642, USA. John-Treanor@urmc.rochester.edu
Betts
R F
RF
D000368:Aged; D000914:Antibodies, Viral / Q000096:biosynthesis; D003080:Cold Temperature; D004311:Double-Blind Method; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006386:Hemagglutination Tests; D006801:Humans; D009980:Influenza A virus / Q000276:immunology*; D009981:Influenza B virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D009735:Nursing Homes; D014613:Vaccines, Attenuated / Q000276:immunology
D000914:Antibodies, Viral; D007252:Influenza Vaccines; D014613:Vaccines, Attenuated