Assessment of antibody titres in VZV and saline blister fluid compared with those in total donor serum. Total IgA, IgM, and IgE antibody titres were analyzed within matched BF aspirates from saline control (n = 4) and VZV (n = 5) challenge sites as well as from donor sera (n = 6) on day 7 after VZV or saline challenge, using an ELISA-based technique. Each symbol on the plot represents one individual. Data were analyzed with Kruskal‒Wallis test with Dunn’s multiple comparison post-test. BF, blister fluid; ns, not significant; VZV, varicella-zoster virus.