VWF and dengue disease: Day 5: NS1 antigen and dengue IgM positive, dengue IgG negative; factor V Leiden: negative; Von Willebrand factor (ristocetin cofactor activities): 107 (reference: 50–150); protein C: 81 (reference: 70–140); protein S: 26 (reference: 59–118); dengue serotype 1 (Ct: 14.46)