We thank all members of the PrakashLab for their feedback. We thank J. Cybulski and D. Ott for their discussions and engagement in the early phases of this project; F. Hol for his assistance with the soft-lithography fabrication; and K. Hong (Yeh Lab, Stanford University) for her assistance with the malaria samples. M.S.B. acknowledges fellowship support from the Stanford School of Medicine Dean’s Postdoctoral Fellowship. M.P. acknowledges support from the Pew Foundation, Moore Foundation, National Science Foundation Career Award and the National Institutes of Health (NIH) New Innovator Award. This work was supported by the Stanford Clinical and Translational Science Award (CTSA) to Spectrum (UL1 TR001085). The CTSA programme is led by the National Center for Advancing Translational Sciences (NCATS) at the NIH. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.