Lung clearance of naive and reinfected mice after <i>B. pertussis</i> infection.

<p>(A) Number of colony forming units (cfu) in challenge culture (C.C.) was confirmed before challenge. All other cfu were determined in lung of challenged mice (mean n = 3). A large fraction of the original infection dose was traceable in the lungs of mice 2 hours p.i. Bacteria were able to colonize and multiply approximately 100-fold at 7 days p.i. After one week, the mice were able to clear bacteria, which resulted in cleared lungs (2 out of 3 mice) at the last time point (day 28 p.i.). (B) Reinfection was performed at 56 days after primary infection and the number of cfu were counted after 4 hours p.i. While reinfected mice were able to clear <i>B. pertussis</i> from the lungs within 2 days p.i., naive mice showed a similar pattern as observed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0104548#pone-0104548-g001" target="_blank">Figure 1A</a>.