CD40LG and dengue disease: Conversely, antibody positivity rate in Dengue and Chikungunya groups diverged; while presence of anti-Dengue IgM was confirmed on 228 (13.4%%) out of 1,700 samples tested, Chikungunya specific IgM antibodies were detected on 5,244 (74.4%) out of 7,349 samples (Table 2).