A live attenuated influenza A(H5N1) vaccine induces long-term immunity in the absence of a primary antibody response.

Background: Highly pathogenic avian influenza A(H5N1) causes severe infections in humans. We generated 2 influenza A(H5N1) live attenuated influenza vaccines for pandemic use (pLAIVs), but they failed to elicit a primary immune response. Our objective was to determine whether the vaccines primed or established long-lasting immunity that could be detected by administration of inactivated subvirion influenza A(H5N1) vaccine (ISIV).

Experimental infection of adults with recombinant wild-type human metapneumovirus.

Background: Human metapneumovirus (HMPV) causes lower respiratory tract infections in young children. rHMPV-SHs is a recombinant HMPV (rHMPV) based on a biologically derived wild-type HMPV strain. We characterized its infectivity and immunogenicity in healthy adults to determine whether it would be suitable for use as the parent virus for the development of live attenuated rHMPV vaccines.

An open-label phase I trial of a live attenuated H2N2 influenza virus vaccine in healthy adults.

Background: Live attenuated influenza vaccines (LAIV) against a variety of strains of pandemic potential are being developed and tested. We describe the results of an open-label phase I trial of a live attenuated H2N2 virus vaccine.

Objectives: To evaluate the safety, infectivity, and immunogenicity of a live attenuated H2N2 influenza virus vaccine.

An open label Phase I trial of a live attenuated H6N1 influenza virus vaccine in healthy adults.

Background: We describe the results of an open label Phase I trial of a live attenuated H6N1 influenza virus vaccine (ClinicalTrials.gov Identifier: NCT00734175).

Methods And Findings: We evaluated the safety, infectivity, and immunogenicity of two doses of 10(7) TCID(50) of the H6N1 Teal HK 97/AA ca vaccine, a cold-adapted and temperature sensitive live, attenuated influenza vaccine (LAIV) in healthy seronegative adults.