Fig. 2

Transmission stage production and virulence of two Schistosoma mansoni populations [SmLE (HS) and SmBRE (LS)]. a Difference in the number of cercariae produced by SmLE (HS) and SmBRE (LS) S. mansoni populations during 4 weeks of the patent period (week 4 to 7 post infection). SmLE (HS) population was shedding more cercariae than SmBRE (LS) population of parasite at all the time points. b Survival of the infected and control Biomphalaria glabrata (Bg26 inbred) snails from the first day of cercarial shedding to day 22 after the first shedding. Infection with SmLE (HS) parasites resulted in greater snail mortality than infection with SmBRE (LS) parasites. c Infected snails showed a decrease in laccase-like activity in the snail hemolymph compared to uninfected ones. Snails infected with SmLE (HS) parasites showed a greater decrease than that in snails parasitized by SmBRE (LS) parasites. d The overall hemoglobin rate in the hemolymph was reduced by the presence of schistosome parasites. However, the reduction was greater when snails are infected with the SmLE (HS) parasites. *P < 0.05, **P ≤ 0.01, ***P ≤ 0.001