The emergence of chikungunya virus in the Americas means the affected population is at risk of developing severe, chronic, rheumatologic disease, even months after acute infection. Accurate diagnostic methods for past infections are essential for differential diagnosis and consequence management. This study evaluated three commercially-available chikungunya Immunoglobulin G immunoassays by comparing them to an in-house Enzyme-Linked ImmunoSorbent Assay conducted by the Centers for Disease Control and Prevention (Atlanta, Georgia, United States). Results showed sensitivity and specificity values ranging from 92.8% - 100% and 81.8% - 90.9%, respectively, with a significant number of false-positives ranging from 12.5% - 22%. These findings demonstrate the importance of evaluating commercial kits, especially regarding emerging infectious diseases whose medium and long-term impact on the population is unclear.

Commercial chikungunya virus (CHIKV)-specific IgM detection kits were evaluated at the Centers for Disease Control and Prevention (CDC), the Public Health Agency of Canada National Microbiology Laboratory, and the Caribbean Public Health Agency (CARPHA). The Euroimmun Anti-CHIKV IgM ELISA kit had ≥ 95% concordance with all three reference laboratory results. The limit of detection for low CHIK IgM+ samples, as measured by serial dilution of seven sera up to 1:12,800 ranged from 1:800 to 1:3,200. The Euroimmun IIFT kit evaluated at CDC and CARPHA performed well, but required more retesting of equivocal results. The InBios CHIKjj Detect MAC-ELISA had 100% and 98% concordance with CDC and CARPHA results, respectively, and had equal sensitivity to the CDC MAC-ELISA to 1:12,800 dilution in serially diluted samples. The Abcam Anti-CHIKV IgM ELISA initially had high performance at CDC and CARPHA, but at CDC, performance was inconsistent between lots. After replacement of the biotinylated IgM antibody controls with serum containing CHIKV-specific IgM and additional quality assurance/control measures, the Abcam kit was rereleased and reevaluated at CDC. The reformatted Abcam kit had 97% concordance with CDC results and limit of detection of 1:800 to 1:3,200. Two rapid tests and three other CHIKV MAC-ELISAs evaluated at CDC had low sensitivity, as the CDC CHIKV IgM in-house positive controls were below the level of detection. In conclusion, laboratories have options for CHIKV serological diagnosis using validated commercial kits.