Figure 3.

Multiple-dose фA1122 phage treatments did not improve treatment efficacy. Schematic representation of mouse treatment regimens (A) and survival curves (B). C57BL/6J mice were IN infected with 10 × LD₅₀ of Y. pestis Kim53. For IN phage treatment, mice were inoculated with 35 µL of 1 × 10⁹ фA1122 PFU; IP injection included the administration of 0.5 mL of 1 × 10⁹ фA1122 PFU. The treatment regimens were as follows: one dose of IN фA1122 at 5 hpi (n = 22; light blue line), two doses of IN фA1122 at 5 hpi and 24 hpi (n = 12, olive green line), one dose of IN фA1122 at 5 hpi + IP injections at 24 and 48 hpi (n = 17, green line) and one dose of IN фA1122 at 5 hpi + IP injections for 6 days, every 24 h (n = 10, purple line). Control mice: n = 17, black line. (B): Statistically significant differences between the control group and phage-treated groups are denoted by asterisks (*** p < 0.0001; log-rank (Mantel–Cox) test).