Identification of Aichi Virus Infection by Measurement of Immunoglobulin Responses in an Enzyme-Linked Immunosorbent Assay

Using inhibitory enzyme-linked immunosorbent assay, seroconversions to Aichi virus were detected in 24 (42.9%) of 56 patients with gastroenteritis in six outbreaks. Virus-specific immunoglobulin M (IgM) was detected in convalescent-phase sera from 7 of 24 patients. Of the other 17 patients, 12 developed a significant increase in both IgA and IgG levels and 5 developed a significant increase in IgG alone.