This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goals of this study are to assess the safety, reactogenicity, and immunogenicity of a novel Vero cell culture-derived whole virus (WV) influenza A/H5N1 vaccine at various dosage levels with or without aluminum hydroxide adjuvant when administered by intramuscular (IM) injection to healthy adults. We hypothesize that a dosage level in the range of 7.5 mg to 15 mg of adjuvanted WV influenza A/H5N1 vaccine, or a dosage level on the range of 7.5 mg to 45 mg of nonadjuvanted WV influenza A/H5N1 vaccine will be well tolerated and will result in acceptable immunogenicity when administered in a 2-dose regimen. Further, we hypothesize that addition of aluminum hydroxide adjuvant will significantly enhance the immunogenicity of the vaccine when similar dosage levels of adjuvanted and nonadjuvanted vaccine (based on HA content) are compared.