Table 2. Worms recovered and the percentage of worm reduction after PZQ pressure.

Passage	Treatment	Mean number of worms ± SD (% reduction)
	(mg/kg of PZQ)	Non-selected	Selected
1	Untreated	32.15±9.66	Υ
	2×100 mg	27.84±11.03 (13.42)	27.84±11.03 (13.42)
6	Untreated	42.90±14.10	17.88±7.63
	3×300 mg	17.22±10.59 (59.88)*	14.00±8.78 (21.68)*
7	Untreated	77.22±12.32	67.83±18.33
	3×300 mg	40.69±14.36 (47.30)**	57.94±12.09 (14.58)**

*, ** p<0.05 (Non-selected vs. Selected). N = 20 mice were used for each group.

^ΥThe initial control group is the same for the Non-selected and Selected populations.

Mean numbers of worms recovered from treated and untreated mice after the first, sixth and seventh rounds of PZQ treatment. % Percentage of reduction of Selected (S) and Non-selected (N) worms obtained after treatment with PZQ at 2×100 mg/kg and 3×300 mg/kg. For each round, eggs produced by the worms that had survived the drug treatment were used to infected snails, and the cercariae obtained were used to infect a new set of mice.

*, ** P≤0.05 indicates a significant difference between Selected and Non-selected parasites in the percent worm reduction upon PZQ treatment (Mann Whitney).

SD: standard deviation.