TABLE 2.
Clone genotype | No. of mice infecteda/no. analyzed with the following spirochete dose: |
ID50 (90% CI)c | ||||
---|---|---|---|---|---|---|
1 × 103 | 1 × 104 | 1 × 105 | 1 × 106 | 1 × 107 | ||
Wild type | 0/6 | 1/6 | 3/6 | N/A | N/A | 3.6 × 104 (7.9 × 102–1.6 × 106) |
Δbb0318/pBSV2G | N/A | 0/6 | 0/6 | 1/6b | 5/6 | 3.5 × 106 (1.0 × 106–1.2 × 107) |
Δbb0318/pBSV2G bb0318 | 0/6 | 1/6 | 4/6 | N/A | N/A | 4.8 × 104 (2.1 × 103–1.0 × 106) |
Mouse infection was determined 3 weeks postinoculation by positive reisolation of spirochetes from the ear, bladder, and joint tissues unless otherwise noted. N/A, not applicable.
Positive reisolation of spirochetes from bladder and joint tissues only.
The 50% infectious dose (ID50) is the number of spirochetes required to infect 50% of the mice inoculated. The ID50 values and associated 90% confidence intervals (90% CI) were calculated using probit regression analysis (JMP, version 12.2.0; SAS Institute, Inc.).