Diagnostic laboratory tests Stained smears from the local lesion or of blood from dead animals often show chains of large gram positive rods Anthrax can be identified in dried smears by immunofluorescence staining techniques An elisa has been developed to measure antibodies against edema and lethal toxins but the test has not been extensively studied Some public health laboratories may also have nucleic aci amplification assays availableDiagnostic laboratory tests • Stained smears from the local lesion or of blood from dead animals often show chains of large gram positive rods. Anthrax can be identified in dried smears by immunofluorescence staining techniques. • An ELISA has been developed to measure antibodies against edema and lethal toxins, but the test has not been extensively studied. • Some public health laboratories may also have nucleic acid amplification assays available