Infection with rhMPV-WT led to a significant increase in the baseline Penh values, indicating increased obstruction of the airways, compared to mock-infected mice, starting at day 3, peaking on day 5 and then gradually returning to baseline by day 14 p.i. In addition, rhMPV-WT infection was associated with significant dose-dependent increase in AHR in response to aerosolized methacholine (Figure 1C). This evidence concerns the gene AHR and infection.