Sun P, et al. - Researchers compared HIV⁺ and HIV^- individuals in terms of B and T memory cells elicited by a single dose monovalent 2009 influenza A (H1N1) vaccine. Furthermore, they assessed the influence of the prior seasonal vaccines to the immunogenicity of this vaccine. Findings demonstrated a significantly better response to monovalent H1N1 vaccine in participants with a prior trivalent live-attenuated vaccine (LAIV) seasonal vaccine vs. a trivalent inactivated vaccine (TIV) seasonal vaccine. Excluding LAIV participants, there was no difference between the HIV⁺ and HIV^- subject groups in terms of memory B cells (B_Mem). At 6 months, a decline was noted in the BMem response.