We used DENV NS1 protein to evaluate DENV‐specific response in acute patients because ZIKV and DENV NS1 share 53–56% of amino acid identity 33. Moreover, NS1 has gained considerable attention for early dengue diagnostic tests. All healthy donors and 75% of acute patients in our cohort had indications of previous dengue, thus it was expected that they would be great responders of NS1 DENV. Considering this, we assessed DENV‐specific T cell response against a pool of NS1 from all four serotypes in PBMCs isolated from acute patients from DENV‐exposed donors by IFNγ ELISPOT assay (Fig. 3a).