CD40LG and scrub typhus: The best compromise for the ELISA OD cut-off for acute scrub typhus diagnosis with IgM antibodies was likely to be in the range of 0.8–1.0 with sensitivity, specificity and AUROCC for ELISA OD at ≥1.0 of 88.2%, 87.7%, and 0.88 for admission, 83.9%, 86.1%, and 0.85 for follow-up and of 65.7%, 91.3%, and 0.79 for combined samples.