Evaluation of the infectivity, immunogenicity, and efficacy of live cold-adapted influenza B/Ann Arbor/1/86 reassortant virus vaccine in adult volunteers.
A cold-adapted (ca) influenza B reassortant that derived two genes encoding the hemagglutinin and neuraminidase from influenza B/Ann Arbor/1/86 wild-type virus and six internal RNA segments from ca influenza B/Ann Arbor/1/66 virus was evaluated in 66 adult volunteers having a serum hemagglutination inhibition antibody titer less than or equal to 1:8. The ca reassortant was attenuated and elicited the production of systemic and local antibodies; the 50% human infectious dose was 10(6.4) TCID50. Six weeks after vaccination, 12 unvaccinated volunteers and 13 recipients of ca virus (10(7.5) TCID50) were challenged experimentally with homologous wild-type influenza B virus. The ca vaccine completely protected against illness, and the magnitude of shedding was 50-fold less in vaccinees than in unimmunized controls, five of whom became ill. These findings indicate that the six internal RNA segments of the ca influenza B/Ann Arbor/66 donor virus confer desirable properties of a live virus vaccine to a reassortant derived from a virulent virus. Such reassortants may be suitable vaccines for healthy adults.
Clements
M L
ML
Center for Immunization Research, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Maryland 21205.
Snyder
M H
MH
Sears
S D
SD
Maassab
H F
HF
Murphy
B R
BR
D000328:Adult; D000914:Antibodies, Viral / Q000096:biosynthesis*; D004306:Dose-Response Relationship, Immunologic; D004797:Enzyme-Linked Immunosorbent Assay; D006385:Hemagglutination Inhibition Tests; D006389:Hemagglutinins, Viral / Q000235:genetics; D006801:Humans; D009981:Influenza B virus / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D007252:Influenza Vaccines / Q000009:adverse effects / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D009439:Neuraminidase / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D014613:Vaccines, Attenuated / Q000009:adverse effects / Q000276:immunology; D014614:Vaccines, Synthetic / Q000009:adverse effects / Q000276:immunology; D014779:Virus Replication
D000914:Antibodies, Viral; D006389:Hemagglutinins, Viral; D007252:Influenza Vaccines; D012367:RNA, Viral; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; D009439:Neuraminidase