[IgM antibody detection in acute viral diseases, 1995-2004: analysis of data collected at a commercial diagnostic laboratory in Japan].

: We analyzed data from tests for virus-specific IgM in 376,000 serum specimens sent to a commercial diagnostic laboratory from clinics nationwide between 1995 and 2004. IgM antibodies to measles, rubella, mumps, parvo B19, and varicella-zoster viruses were tested using IgM-capture ELISA kits. Among specimens, 254,000 (68%) had documentation of age, of which 56% were sera from persons or = 20 years of age. Monthly or yearly trends in IgM antibody-positive tests in or = 20 y specimens were similar, indicating that infections occur simultaneously in both children and adults. Adult IgM-positive specimens came from internal medicine clinics and from dermatology clinics for measles; from dermatology and obstetrics clinics for rubella and parvo B19; from otolaryngology clinics for mumps; and from dermatology and otolaryngology clinics for varicella-zoster virus. Analysis of large numbers of IgM test results at regular intervals may contribute to understanding of the epidemiology of these viral diseases in Japan.