AR and infection: By 28 days post aerosol infection,which is about one week before mice would succumb to disease without effectivedrug intervention, multiple lesions coalesce and exhibit extensive lesionnecrosis (Fig. 2E, F).Necrotic foci contained high numbers of both intracellular bacteria [withinmΦ and multinucleated giant cells (55%)] (Fig. 2G) as well as extracellular AR+bacilli [residing in alveolar spaces filled with necrotic cellular debris(40%)] (Fig.2H).