TvGM6 ELISA using sera from infections with (A) T. vivax IL2172 (drug-sensitive) and (B) T. vivax Komborodougou (drug-resistant). TcoGM6 ELISA using sera from infections with (C) T. congolense O2J (drug-sensitive) and (D) T. congolense KONT2/133 (drug-resistant). All animals were treated with 3.5mg/kg of diminazene diaceturate at the dates indicated by the arrows, (D) was treated a second time with 1 mg/kg isometamidium chloride. For figures (A), (C) and (D) parasitaemia score can be related to approximate amounts of parasites as follows: 2 (1-10/preparation), 3(1-2/field), 4 (1-10/field), 5 (10-50/>50 field), 6 (>100/field). TvGM6 or TcoGM6 ELISA OD (£), whole trypanosome lysate ELISA OD () and parasitaemia () are indicated. Arrows indicate trypanocidal treatment, and the x-axis is the threshold for positivity.