Heatmap of signal intensity of antibody binding to seroreactive polypeptides on the microarray. A three-colour gradient display of intensity of antibody binding to 281 P. falciparum and 177 P. vivax seroreactive polypeptides is shown for samples collected during a community-wide mass blood survey and passive case detection at a malaria clinic in Tak Province, Thailand. Samples are segregated according to infectious status and health condition (presenting symptoms or not) at the time of sample collection into four major groups: healthy, asymptomatic malaria, non-malaria illness and symptomatic malaria. Results from qPCR screening are shown as negative or the species (Pf, Pv or Pf + Pv mixed-species) identified in the sample. The coloured gradient represents Z-score values of signal intensity in relation to malaria-unexposed controls, ranging from 0 to ≥5. Individual samples appear as columns, ranked from left to right in their totals of binding to the array’s proteins; seroreactive polypeptides appear as rows, ranked from top to bottom in their mean values of antibody binding for all plasma.