Obesity in adolescents does not influence early immune responses to influenza vaccination.

Background: Obesity has been linked to reduced vaccine responses against tetanus, hepatitis B and influenza. Data on the influence of paediatric obesity on influenza vaccine response is still lacking and this study aims to fill the gap.

Methods: A total of 30 children with obesity and 30 children with normal weight, aged 12-18 years, were recruited. Participants were vaccinated with a tetravalent influenza vaccine. Blood was collected prior to the vaccination and again four weeks later. The humoral response was assessed with haemagglutinin inhibition assay. The cellular response was assessed with T-cell stimulation assays measuring TNF-α, IFN-γ, IL-2 and IL-13.

Results: Of the 29/30 from the study group and 30/30 from the control group finished both visits. Seroconversion occurred for > 90% of participants in both groups for the A/H1N1, A/H3N2 and B/Victoria strains, but the B/Yamagata strain had lower seroconversion rates (93% in the study group and 80% in the control group). 97-100% of participants from both groups had adequate serological responses following vaccination. Cellular responses were similar between the two groups post-vaccination.

Conclusions: Early humoral and cellular immune responses to influenza vaccinations are similar among adolescents with obesity and normal weight.