Höfundar:
Íris Kristinsdóttir, Ásgeir Haraldsson, Siggeir Fannar Brynjólfsson, Tryggvi Helgason, Björn Rúnar Lúðvíksson, Elena Gianchechhi, Ilaria Razzano, Emanuele Montomoli, Valtýr Thors
Introduction: Obesity is prevalent worldwide, among both adults and children. Severe complications of influenza infections have been associated with obesity. Furthermore, obesity has been associated with reduced immune responses to hepatitis B and tetanus vaccinations. The study aimed to assess the early humoral and cellular immune responses to influenza vaccinations in adolescents with obesity.
Methods: 60 adolescents aged 12-18 years were recruited, 30 with obesity and 30 with normal weight. Participants were vaccinated with a tetravalent influenza vaccine (2020/2021 season). Venous blood samples were collected prior to the vaccination and again four weeks after. Body composition measurements were done. The humoral immune response was assessed with haemagglutination inhibition (HAI) assay. Seroconversion was defined as a >4-fold increase in titres. The cellular immune response was assessed with T-cell stimulation assays.
Results: 29/30 participants from the study group and 30/30 from the control group completed the study participation. Seroconversion rates were similar between the two groups, with >90% in both groups seroconverting against the A/H1N1, A/H3N2 and B/Victoria strains, but 93% in the study group and 80% in the control group against the B/Yamagata strain. The two groups had similar post-vaccination T-cell responses to stimulation with the influneza vaccine strains.
Conclusion: Obesity does not affect adolescents’ early humoral or cellular immune responses to influenza vaccinations. Further studies are needed to assess whether the longevity of the immune responses is affected by obesity.