Importantly, both of these clinical isolates induced the accumulation of IL-13 in the whole-lung homogenate at day 4 after infection and airway mucus at 6 after infection (Fig 5, C-E), although significant weight loss was only observed with 12/11-19 (see Fig E9 in this article's Online Repository at www.jacionline.org). Here, IL13 is linked to infection.