An epidemiological investigation of Norwalk virus infection in South Africa

A study was carried out to determine the incidence and seroprevalence of Norwalk virus (NV) in the Pretoria area, South Africa, using a recombinant NV (rNV) immunoassay for the detection of serum IgG antibodies. Maternal antibody was detectable in infants' sera up to approximately 6 months of age. Infection with NV was detected serologically in the second year of life and the seroprevalence of NV IgG rose from 37.1% at 7-11 months of age to 62.1% by the age of 40 years. No significant differences in seroprevalence of NV IgG antibody was evident between subjects of European or African ethnic origin, where overall seroprevalence rates were 56.4% and 53.9% respectively.