Antibody responses to influenza vaccine in pre- and post-lung transplant patients

Background: Although pre-transplant immunization is routinely recommended, this recommendation is based on little data. The primary objective of this study was to compare antibody responses in lung transplant patients who received influenza vaccine before the transplant, within the first six months of transplant, between 13 and 60 months post-transplant, and 110 months or beyond transplant.
Methods: This prospective cohort study included 357 total immunization events performed over five yr to measure H1N1, H3N2, and B antibody responses to the influenza vaccine in pre- and post-lung transplant patients. Geometric mean titers, seroprotection (antibody titer at least 1:40), seroconversion (fourfold increase between pre and post), and mean fold increases were compared.
Results: The geometric mean titer distributions were different for H3N2 and B (ANOVA; p = 0.002 for both). Pre-transplant antibody concentrations were higher compared to the 13- to 60-month group for H3N2 (corrected p = 0.002) and the healthy group for B (corrected p = 0.001). The ≥110-month group had higher seroconversion rates compared to the 13- to 60-month group for H3N2 and B viruses.
Conclusion: Lung pre-transplant patients and the long-term survivors have higher responses to the influenza vaccine than early post-transplant and the transplant control groups.