Development of a Dot-Immunoenzyme Filtration Assay for the Detection of Enterovirus 71 Antigen in Human Serum via Immunoglobulin M

OBJECTIVES: This study evaluated the sensitivity and specificity of a rapid, sensitive dot-immunoenzyme filtration assay to detect enterovirus 71 (EV71) antigen in serum samples from paediatric patients with hand, foot and mouth disease (HFMD), through detection of anti-EV71 immunoglobulin (Ig)M. METHODS: Serum samples from HFMD patients and healthy adult controls were evaluated for the presence of anti-EV71 IgM using a dot-immunoenzyme filtration assay (DIEFA). The results were compared with those obtained using a dot-immunogold filtration assay (DIGFA). The EV71 structural protein VP1 was used as the antigen for both assays. RESULTS: Serum samples from 72 HFMD patients and 54 healthy controls were evaluated. The DIGFA procedure showed a sensitivity of 98.5% and a specificity of 100%, whereas the DIEFA procedure showed a sensitivity of 98.6% and a specificity of 98.0%. There were no significant differences between the assays in either specificity or sensitivity. CONCLUSION: The DIEFA procedure developed in this study has potential as a rapid, simple, sensitive and cost-effective screening technique for detecting EV71 antigen in serum samples from patients with HFMD.