Plasma cytokine or chemokine level, stratified by days after symptom onset. Median, quartiles, and range are shown. The Jonckheere-Terpstra trend test was used to compare cytokine level with disease severity. Horizontal dotted line detection limit of the assay. A Granulocyte colony-stimulating factor. B Interferon (IFN)– lpha;2. C Interleukin (IL)–1 lpha;. D IL-6. E IL-8. F IL-10. G IL-15. H IL-17. I IFN- amma;–induced protein 10. J Monocyte chemoattractant protein–1. K Tumor necrosis factor-α.