Research Question	Possible Study Designs
Submicroscopic parasitemia
What proportion of untreated/unrecognized submicroscopic infections persist asymptomatically?	Retrospective molecular analysis of prior cohort studies where only microscopy was used.
What proportion go on to become microscopically patent and/or symptomatic?
How often do treated patients develop subsequent submicroscopic parasitemia?	Retrospective molecular analysis of therapeutic efficacy studies.
Transmission potential of submicroscopic infections
What proportion of submicroscopic infections harbor or produce gametocytes, and at what density?	Prospective molecular analysis incorporated into cohort studies or national surveys.
Besides gametocyte density, what parasite or human host factors affect human-to-mosquito infectivity?	In vitro membrane feeding assays
How commonly does submicroscopic vs. microscopic malaria in asymptomatics successfully infect mosquitoes? How does this vary in different transmission settings and in different mosquito vectors?	Vectorial capacity studies, estimates of Entomological Inoculation Rate (EIR), mosquito membrane feeding studies in vitro and from patients in surveys and/or cohorts
Diagnostic tests to detect submicroscopic parasitemia and estimate transmissibility
How sensitive does a diagnostic test need to be to identify all those in the infectious reservoir?	Comparative analysis of diagnostic tests incorporated into cohort studies and mass surveys, paired with malaria seroprevalence surveys
How large is the hypnozoite reservoir in P. vivax endemic areas, and how can it be measured?	Studies to identify surrogate markers of latent P. vivax infection