Fig 3. Detection of CHIKV RNA by real-time RT-PCR and IgM antibody specific to CHIKV antigen by rapid test.

Results of 1,295 CHIKV infected patients were shown. Samples were tested by both real-time RT-PCR and rapid test for IgM antibody as described in the Materials and Methods. The Ct value and cut-off index (COI) represent the results of real-time RT-PCR and rapid IgM tests, respectively. COI is based on the ratio of assay signal to cut-off value of which COI≥1 = positive for anti-CHIKV IgM antibody and COI <1 = negative for anti-CHIKV IgM antibody. Curve equations and determination coefficients (R²) are indicated.