Comparison of the immunogenicity of a monovalent influenza A/H1N1 2009 vaccine between healthy individuals, patients with chronic renal failure, and immunocompromised populations.

ABSTRACT

BACKGROUND: Data on the immunogenicity (IG) of the influenza vaccine among patients at high risk of influenza-related complication are limited. METHODS: We studied the antibody titer following a single dose of monovalent 2009 influenza A (H1N1) vaccine between groups of adult patients who were healthy, those with chronic renal failure (CRF), kidney transplant (KT) recipients, and human immunodeficiency virus (HIV)-infected patients. The IG (primary endpoints) was accessed at 4 weeks after vaccination. The secondary endpoint was safety of the vaccine. RESULTS: A total of 293 patients were studied. Patients' mean age was 41(standard deviation [SD], 13.3) years old. At baseline, mean age (P < .001), history of vaccination in a prior year (P < .001), and geometric mean titers (GMT; P < .001) significantly differed between each groups and the majority (70%) of participants had the hemagglutination inhibition titer <110. The IG of the vaccine was highest in the healthy group (71.4 %). The response rate among CRF, KT, and HIV groups was 42.4% (risk ratios [RR], 0.72; 95% confidence interval [CI], 0.5-1.02), 31.9% (RR, 0.51; 95% CI, 0.34-0.76), and 29.7% (RR, 0.42; 95% CI, 0.3-0.6), respectively. The vaccine was well-tolerated in all studied groups. Thirty (10.2%) patients experienced at least 1 adverse reaction but systemic reaction was uncommon (3.4%). CONCLUSIONS: A single dose of monovalent 2009 influenza A (H1N1) vaccine result in poor IG among high-risk populations, including CRF, KT and HIV patients.