FIG 5.

B. pertussis infection induces inflammation of the lung and a decrease in weight gain. (A) After euthanasia, the lung weight was measured and recorded. To observe any weight changes over the course of infection, we calculated the percent weight change for mock-challenged (B), D420-infected (C), and Tohama 1-infected (D) rats. Rat body weights were recorded before infection, as well as immediately posteuthanasia. The percent weight change was calculated by taking the differences between starting weight and end weight and dividing by the initial weight and then multiplying by 100. Results are shown as means ± the SEM (n = 1 to 4). Only one mock-challenge rat weight was measured at days 1, 3, 6, and 9. Weights of 4 mock-challenge rats were recorded at day 12 postinfection. P values were determined by one-way ANOVA (*, P < 0.05; **, P < 0.01; ***, P < 0.001 [(A) compared to mock-challenge group; (B to D) compared to both infection groups]).