More than two of the following symptoms: acute onset fever, severe headache, orbital pain, myalgia, arthralgia, fatigue, a history of travel in a dengue-endemic area during the 15 days before symptom onset or cohabitation with an individual with confirmed dengue, or no travel history but with a rash or positive tourniquet test AND leucopoenia or thrombocytopenia or serum IgM positivity. This evidence concerns the gene CD40LG and dengue disease.