Blood lymphocyte distributions, serum immunoglobulin and cytokine levels, and serum IgE and IgG anti-varicella zoster virus (VZV) levels were measured in an atopic girl (age 15 yr) who developed shingles 10 yr after infection with chicken pox. Before, during, and 5 months after the shingles episode, the child's distributions of blood lymphocytes (excluding CD23+) and serum immunoglobulin levels (excluding IgE) were within the normal ranges. Her blood level of CD23+ lymphocytes decreased >50% during the shingles episode and remained low thereafter. Her serum level of IgE was elevated before and during shingles (154 and 168 IU/ml, respectively), but was reduced after recovery from shingles (<100 IU/ml). Before, during, and after shingles, her serum contained IgE and IgG anti-VZV antibodies. Before, during, and after shingles, low levels of IFN-γ were detected in serum, but neither IL-1β nor IL-4 were detected. Before shingles, low levels of IL-10 were detected in serum; during shingles, the serum level of IL-10 was increased 30-fold; it subsequently diminished at 5 mo after shingles. The role of IgE in immunity against varicella zoster virus (VZV) has not previously been studied. Our observations in this patient suggest that immunomodulation of IgE and accessory proteins may play a role in VZV pathogenesis.