Fig. 1

Study cohort characteristics. Individuals with a confirmed secondary DENV infection were recruited for the study at the onset of fever and followed up for progression to DF (n = 7) or DHF (n = 10). A–D. Clinical parameters determined in the study include age (A), gender (B) and CT-value (C), and anti-DENV IgG antibody titres (D). Boxes represent the 25th to 75th percentiles, whiskers show the range (minimum to maximum), and lines represent the median of biological replicates. The dotted line depicts the average antibody background levels of uninfected healthy controls (n = 5). Line plots depict mean ± SD. Significance was determined by the Kruskal–Wallis test (A), the Chi-square test (B), and the Mann-Whitney test (C, D), *p < 0.05. E–K. Mean chemokine levels. CCL2 (E), CCL17 (F), CXCL5 (G), CXCL8 (H), CXCL9 (I), CXCL10 (J) and CXCL11 (K) were determined in plasma samples of study participants. Boxes represent the 25th to 75th percentiles, whiskers show the range (minimum to maximum), and lines represent the median of 7 (DF) and 10 (DHF) biological replicates. The dotted line depicts the average antibody background levels of uninfected healthy controls (n = 5). Significance was determined by the Mann-Whitney test. *p < 0.05, **p < 0.01