CD40LG and leptospirosis: A study of patients from two hospitals in the Amazon region with acute undifferentiated febrile illnesses detected leptospirosis specific-IgM antibodies seroconversion in 14.7% of 227 patients tested [34], while in a cross-sectional seroepidemiology survey in two indigenous Shuar communities in the Amazon-Morona Santiago province, 50% of 216 were positive for IgG antibodies [55].