209 strated that combining NS1 Ag to an early serologic test improved Dengue diagnosis. If IgM has been extensively evaluated, there are few data about IgA detection in association to NS1. The purpose of these clinical studies was to evaluate the efficiency of combining dengue NS1 Ag and anti-NS1 IgA antibodies for the detection of Dengue infection during the acute phase in Asian populations. Methods & Materials: Evaluated kits were Platelia TM Dengue IgA Capture associated to Platelia TM

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... NS1 Ag for ELISA part and RDT Dengue IgA/IgG associated to Dengue NS1 STRIP for rapid testing. Sensitivity was performed on 216 samples from patients with clinically confirmed Dengue of 3 Asian countries: Cambodia (n=135), India (n= 31) and Singapore (n=50). Specificity was evaluated on 101 sera from 50 healthy Indian donors and 51 febrile patients from Cambodia for which dengue infection has been excluded. Results: Depending on the population, the sensitivity ranged from 48.5% to 93.3% for Platelia TM Dengue IgA Capture assay versus 48.9% to 90.3% for IgM ELISA and 50% to 100% for the IgA rapid test. When NS1 and IgA tests were combined, the sensitivity reached 93.5% to 98.0% for the ELISAs and 94.1% to 100% for the rapid tests, compared to 94.9% for an "IgM+NS1" combination. The overall specificity of the NS1 and IgA combination in ELISA and rapid test assays were 95,9% and 96,0% respectively. The analysis of NS1 and IgA ELISAs sensitivity related to the sampling time after fever onset in Cambodia population showed that NS1 assay sensitivity was lower and decreased earlier (day 5) in secondary infection than in primary one (day 11). Conclusion: Detection of anti-NS1 IgA efficiently completes NS1 antigen detection in the diagnosis of acute dengue infection in Asian populations. The combination performs as well on ELISA as on rapid test format and demonstrates similar performance to "IgM+NS1". Moreover, IgA appears to be especially useful in secondary infections and has also been described to be indicative of more severe outcome in primary infections. http://dx.