Figure 1

Example of buffer substitution's effect on a three-band RDT. Three-band RDT cassettes run with blood of a malaria free subject and the RDT kit's dedicated buffer (1), injection water (2), saline (3), tap water (4) and when run with injection water in absence of blood sample (5). Cassettes "Pf" and "Pv" refer to Plasmodium falciparum or Plasmodium vivax positive samples run with the RDT kit's dedicated buffer. All cassettes show regular control lines, cassette 1 shows the expected result (no test line visible), cassettes 2, 3 and 5 show false positive pan-pLDH and Pf-HRP2 lines, cassette 4 shows a false positive pan-pLDH line, and cassettes "Pf" and "Pv" show the expected results (positive for pan-pLDH and Pf-HRP-2 lines or positive for pan-pLDH line respectively). In the cassette 3, the false positive reaction is partially masked by the background.