title: Antibody response to the non-adjuvanted and adjuvanted influenza A H1N1/09 monovalent vaccines in renal transplant recipients.
abstract: BACKGROUND
  The 2009 pandemic influenza A (H1N1) virus spread rapidly throughout Brazil. Non-adjuvanted and the adjuvanted influenza A H1N1/09 monovalent vaccine were recommended as a single dose to persons at risk including renal transplant recipients (RTR). We analyzed the safety and the immune response of 2 influenza A H1N1/09 monovalent vaccines in RTR, and identified factors influencing the immune response.
  
  
  METHODS
  A total of 78 RTR received a single dose of either influenza A H1N1 2009 monovalent AS03-adjuvanted vaccine or a non-adjuvanted vaccine, and 58 healthy controls received a single dose of non-adjuvanted vaccine. Antibody responses to influenza A H1N1 were measured by hemagglutination inhibition assay and were compared between groups on the day of vaccination and 21-30 days thereafter, using geometric mean titer (GMT), and seroprotection (SP) and seroconversion (SC) rates.
  
  
  RESULTS
  Among RTR, after adjuvanted and non-adjuvanted H1N1 vaccination, the SP rate increased from 16.7% to 61.7% (P < 0.001) and to 50% (P < 0.001), and SC rates were 61.7% and 50%, respectively. For healthy controls, SP rate increased from 25.8% to 89.7% (P < 0.001), and SC rate was 87.9% after vaccination. Pre-vaccination GMT for the adjuvanted and non-adjuvanted RTR vaccine groups and healthy controls was 9.7 (95% confidence interval [CI] 7.3-13.1), 8.9 (95% CI 5.4-14.7), and 12.5 (95% CI8.7-18.2), and significantly increased to 49.8 (95% CI 31.3-79.4, P < 0.001), 43.2 (95% CI 16.3-114.4, P < 0.001), and 323.8 (95% CI 213.9-490.2, P < 0.001), respectively. Deceased-donor type transplant significantly reduced SP (odds ratio [OR] = 4.62, 95% CI 1.36-15.69, P = 0.014) and SC (OR = 6.29, 95% CI 1.89-20.98, P = 0.003) rates, and younger age positively affected SP (OR = 0.11; 95% CI 0.03-0.04, P = 0.001). Adverse events were mild, and renal function showed no change post vaccination.
  
  
  CONCLUSIONS
  RTR vaccinated with either an adjuvanted or non-adjuvanted monovalent influenza vaccine presented poor response compared with healthy controls. Post-vaccination adverse events were mild, and no rejection episode or renal dysfunction was observed.
authors.affiliation: Infectious Diseases Clinic, Department of Internal Medicine, Santa Casa of Sao Paulo School of Medicine, Sao Paulo, Brazil. mcsalles@osite.com.br
authors.forename: M J C
authors.initials: MJ
authors.lastname: Salles
authors.forename: Y A S
authors.initials: YA
authors.lastname: Sens
authors.forename: P
authors.initials: P
authors.lastname: Malafronte
authors.forename: J F
authors.initials: JF
authors.lastname: Souza
authors.forename: L S
authors.initials: LS
authors.lastname: Vilas Boas
authors.forename: C M
authors.initials: CM
authors.lastname: Machado
mesh_terms: D000759:Adjuvants, Anesthesia; D000914:Antibodies, Viral / Q000097:blood*; D001938:Brazil / Q000453:epidemiology; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology; D016030:Kidney Transplantation / Q000276:immunology*; D058873:Pandemics
chemical_list: D000759:Adjuvants, Anesthesia; D000914:Antibodies, Viral; D007252:Influenza Vaccines