We developed a simple antigen capture enzyme immunosorbent assay (AgC-ELISA) for identifying dengue (DEN) virus. The method employed serotype-specific monoclonal antibodies as capture antibodies and an enzyme conjugate of a flavivirus-reactive monoclonal antibody as a detecting antibody. Most DEN virus strains, representing all 4 serotypes isolated from various parts of the tropics, were identical either visually of spectrophotometrically when infected cell culture fluids were used as sources of antigen. The shelf life of the solid phase presensitized with monoclonal antibodies was 4 mth at -15 degrees C. DEN prototype viruses were still identified after storage at -15 degrees C for 1 yr or at room temperature for 1 mth.