A commercial enzyme linked immunosorbent assay (ELISA) for detection of adenoviruses in stool samples was compared with the use of electron microscopy and isolation in Graham 293 cells. Although specific, the ELISA was less sensitive than both electron microscopy and isolation. The ELISA had an overall sensitivity of 78% and a specificity of 100%. The sensitivity was related to the amount of virus particles present in the stool sample, increasing to 90% with about 10(7) viral particles/ml of stool. The ELISA was easy to perform, requiring no instrumentation, and is a useful first line test for detection of adenoviruses in stool samples, especially in laboratories without access to an electron microscope. Wider use of ELISAs should help in evaluating the role of adenoviruses in viral gastroenteritis.