The combined results of two independent experiments are shown (the results of each individual repeat are available as supplemental data in S3 Fig and S5 Fig). Statistical significance was determined using a Mann-Whitney test (A, B and E) or a Fisher exact test (C and D). In A, B and E, the mean and error of the mean is indicated. In C and D, the error bars represent 95% confidence levels. A) WNV (Kunjin strain) PFU per ml in whole mosquito bodies, (****, p < 0.0001; ***, p = 0.0003, **, p = 0.003; Mann-Whitney). B) WNV (Kunjin strain) PFU per ml in saliva (****, p < 0.0001; **, p = 0.001; *, p = 0.01; Mann-Whitney). C) WNV (Kunjin strain) infection rate as determined by the percentage of individuals infected 7 days post an infectious blood meal, n = 32 (***, p = 0.001; Fisher exact test). D) WNV (Kunjin strain) transmission rate as determined by the percentage of infectious saliva expectorated infected 7 days post an infectious blood meal, n = 32 (*, p = 0.03; Fisher exact test). E) Wolbachia density 7 days post an infectious blood meal in transiently infected and the stable transinfected lines (****, p < 0.0001; Mann-Whitney).