title: Reduced immune response to influenza A (H1N1) 2009 monovalent vaccine in HIV-infected Japanese subjects.
abstract: We evaluated the immunogenicity and safety of the influenza A (H1N1) 2009 monovalent vaccine in HIV-infected Japanese subjects. A total of 182 HIV-infected and 42 HIV-uninfected subjects were enrolled, and antibody (ab) titers were measured by hemagglutination-inhibition assay at baseline and 32.3±10.4 and 29.7±3.3 days after vaccination, respectively. In the HIV-infected cohort, ab titers ≥ 1:40 at baseline and post-vaccination were 12.6% and 49.5%, respectively. The seroconversion rate, defined as either an ab titer ≤ 1:10 before and ≥ 1:40 after or ≥ 1:10 before and ≥ 4-fold increase in ab titer, was only 38.5% in the HIV-infected cohort, whereas the rate was 85.7% in the HIV-uninfected cohort. Multivariate logistic regression analysis showed that the CD4 cell count was the only significant predictor of a positive vaccine response. There were no serious adverse events in any of the subjects receiving the vaccine. Additional study is warranted to identify a more effective method of vaccinating HIV-infected Japanese subjects.
authors.affiliation: Department of Infectious Diseases, Tokyo Metropolitan Komagome Hospital, 3-18-22, Honkomagome, Bunkyo-Ku, Tokyo 113-8677, Japan. naokiy@cick.jp
authors.forename: Naoki
authors.initials: N
authors.lastname: Yanagisawa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Maeda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ajisawa
authors.forename: Akifumi
authors.initials: A
authors.lastname: Imamura
authors.forename: Akihiko
authors.initials: A
authors.lastname: Suganuma
authors.forename: Minoru
authors.initials: M
authors.lastname: Ando
authors.forename: Naohide
authors.initials: N
authors.lastname: Takayama
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Okuno
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood*; D000917:Antibody Formation; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control; D007564:Japan; D008297:Male; D008875:Middle Aged; D014611:Vaccination
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines