FIG 1.
Tissue burdens of infectious and noninfectious B. burgdorferi 1 h after i.v. inoculation. BALB/c mice were inoculated retro-orbitally with 1 × 108 B31-A3 (n = 10), B31A (n = 5), or B314 (n = 5). Bacterial burdens in the spleen, bladder, joint, and ear are significantly lower for B31A than for B31-A3. Blood burdens of B314 are significantly higher than those of B31A and B31-A3. Bacterial burdens are similar between noninfectious strains B314 and B31A as well as infectious strain B31-A3 in all other tissues analyzed. An asterisk indicates statistical significance determined by Mann-Whitney unpaired t test (P < 0.05).