Fig 5. Rickettsial loads during flea infection.

A) Fleas were exposed, independently, to R. felis WT- (black) or R. felis sca1::tn-infected bloodmeals (teal) at an infectious dose of 1.5 x 10¹⁰ rickettsiae for 48 hours. Data are representative of mean ± SEM from three experiments for a total of 60 fleas with 3 technical replicates. B) Feces collected from exposed fleas were assessed for rickettsial enumeration by qPCR and standardized to 1 mg of feces. C) Fleas were exposed, independently, to R. felis WT- (black) or R. felis sca1::tn-infected bloodmeals (teal) at an infectious dose of 5 x 10¹⁰ rickettsiae for 48 hours. Data are representative of mean ± SEM from two experiments for a total of 20 fleas with 3 technical replicates. D) Rickettsial loads per 1 mg of feces collected from fleas exposed to a high dose of rickettsiae. Significance was assessed at a 95% confidence interval (* p<0.05; ** p<0.01) by two-way ANOVA with Bonferroni’s multiple-comparison test to assess variation in the means from wild-type over time.