CD40LG and scrub typhus: None of the patients who were followed up for 18 months were positive for IgM; however, one patient was positive for IgG using the commercial kit of company C. Eight of 12 patients showed positive results, corresponding to a positivity rate of 66.7% at 18 months (Table 1) using the commercial kit of company D. A follow-up study regarding Ab titers was performed in healthy individuals who had recovered from scrub typhus.