Increased sensitivity of a rotavirus serotyping enzyme-linked immunosorbent assay by the incorporation of CaCl2

Abstract The sensitivity of a rotavirus serotyping enzyme-linked immunosorbent assay (ELISA) was improved by the addition of 0.5 mM CaCl 2 to the washing buffer and reagent diluent. Twenty-nine of 63 (46%) previously untyped bovine and equine faecal rotavirus samples were serotyped in the modified assay. A differential response to Ca 2+ ions was noted for different G-serotypes suggesting that serotyping assays performed without the inclusion of CaCl 2 in the assay buffers may produce biased results.