(A) Statistical analysis of mean Ct values in different matrices within respective trial groups. (B) Statistical analysis of mean Ct value recorded in blood between virulent and attenuated strains; * statistically significant (T1, blood vs. oral and rectal swabs, p = 0.0335 and p = 0.0450, respectively), ** statistically significant (T2, blood vs. rectal swabs, p = 0.0011), *** statistically significant (T2, blood vs. oral swabs, p < 0.0001), **** statistically significant (Pol18 vs. NH/P68, p = 0.004), ns—not significant. The boxes represent the 50% between the 25 and 75% quartiles. The line inside the box indicates the median. The top and bottom lines denote maximum and minimum values.