CD40LG and dengue disease: Methods:All patients with documented DVI during a recent epidemic in Pakistan also underwent diagnostic testing for Salmonella enterica serovar Typhi. The diagnosis of DVI was made based on clinical findings and the positive results for dengue non-structural protein 1 antigen (NS1Ag) and/or dengue IgM antibody (anti-D IgM) during the acute phase of febrile illness. Patients with positive test results for Salmonella typhi (S. Typhi) IgM also had their blood cultures done.