Fig. 2.
Comparison of the kinetics of Norwalk virus (NV)-specific serum antibody isotype responses in human volunteers experimentally infected with NV. Samples were collected from persons infected (n = 18) with NV on prechallenge and on days 7, 14, 28, and 180 postchallenge and were analyzed for NV-specific IgG and IgA by duplex DELFIA and IgM by ELISA. Results are expressed as log10 of geometric mean titer (GMT) for IgM and micrograms of immunoglobulin per milliliter for geometric mean concentrations (GMC) of IgG and IgA.