Background reactivity among healthy individuals in the control groups.

<p>A) Heatmap showing the overall reactivity of the control groups used in this study: US naïve subject, corresponding to area with no endemic transmission of leptospirosis, blood donors from Salvador, city with endemic transmission and healthy individuals residing in an urban slum community in Salvador, high risk area. B) Cumulative reactivity of all the antigens present in the array for the 3 control groups. Healthy individuals from area with high endemic transmission show significantly higher sero-reactivity (<i>p</i><0.05, marked with a star) than individuals from regions with endemic or non-endemic transmission of leptospirosis.