Resolution of MAIT cell activation (as defined by CD38 and granzyme B expression) was seen in the convalescent blood sample (collected at least 10 days after the onset of fever) from patients with dengue fever, although resolution was incomplete in the case of granzyme B. IL‐18 levels were also decreased in the convalescent sample, with a correlation between IL‐18 levels and IL‐18Ra expression on MAIT cells, and IL‐18Ra expression on MAIT cells and MAIT cell activation. Here, CD38 is linked to dengue disease.