title: Safety and immunogenicity of a 2009 influenza A (H1N1) vaccine in hemodialysis patients.
abstract: A worldwide vaccination campaign against the 2009 pandemic influenza A (H1N1) virus was launched among high-risk subjects, including hemodialysis patients. The long-term immunogenicity of an influenza vaccine has not been investigated in hemodialysis patients. This study aimed to (1) assess the long-term immunogenicity of a monovalent non-adjuvanted influenza A (H1N1) vaccine in hemodialysis patients and (2) determine the safety of this vaccine. We conducted a prospective cohort study of 44 hemodialysis patients and 149 healthy controls in 2010. All of the participants received a single dose of the monovalent non-adjuvanted 2009 influenza A (H1N1) vaccine. The level of antibodies was measured at baseline and at 4 and 24 weeks post-vaccination using a hemagglutination inhibition assay. The outcomes were the percentages of participants who achieved seroconversion and seroprotection (titer ≥ 1:40) 4 and 24 weeks after vaccination. At 4 weeks post-vaccination, seroconversion was observed in 17 (38.6%) of the hemodialysis patients and 94 (63.1%) of the controls (P=0.056), and protective titers were obtained in 22 (50%) of the hemodialysis patients and 100 (67.1%) of the controls (P=0.426). At 24 weeks post-vaccination, immunogenicity decreased in both the hemodialysis patients and the controls, but there were no significant differences between the hemodialysis patients and the controls in the seroconversion rate (27.3% versus 36.9%, P=0.526) or the seroprotection rate (38.6% versus 48.3%, P=0.996). No differences in adverse events were observed between the hemodialysis patients and the controls. In summary, the 2009 influenza A (H1N1) vaccine elicits a similar immune response in both hemodialysis patients and healthy controls, but immunity declines 24 weeks after vaccination in both groups. Hemodialysis patients should at least be vaccinated annually against the influenza virus.
authors.affiliation: Department of Medicine, Srinakharinwirot University, Royal Irrigation Hospital, 222, Tiwanon Road, Kwang Bangtalat, Pakkret, Nonthaburi, Thailand. lpaungpaga@yahoo.co.uk
authors.forename: Paungpaga
authors.initials: P
authors.lastname: Lertdumrongluk
authors.forename: Siribha
authors.initials: S
authors.lastname: Changsirikulchai
authors.forename: Chutatip
authors.initials: C
authors.lastname: Limkunakul
authors.forename: Poonsuk
authors.initials: P
authors.lastname: Prachukthum
authors.forename: Prapaipun
authors.initials: P
authors.lastname: Punpiput
authors.forename: Rungtiva
authors.initials: R
authors.lastname: Buppanharun
authors.forename: Chuencheevit
authors.initials: C
authors.lastname: Chotpitayasunondh
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D015331:Cohort Studies; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines