An 8 year old girl was admitted to hospital with the typical clinical features of Guillain-Barré syndrome (GBS) after recovering from varicella. Onset of the disease was just two weeks after the onset of varicella in her young sister. Examination of cerebrospinal fluid and nerve conduction studies showed typical findings of GBS. Although serum from both the patient and sister were analysed for autoantibodies to gangliosides and myelin P0 protein, IgM anti-GM1 antibody and anti-GD1b antibody were only detected in the patient. HLA DR haplotypes were quite different between the two subjects. This suggests that these autoantibodies may play an important role in the pathogenesis of GBS after varicella zoster virus infection.