Eighteen (60%) of 30 hospitalized patients infected with 2009 pandemic influenza A (H1N1) with chest X-rays had abnormal findings while all 22 with chest CT scans had abnormal findings (Table 4) . Similarly, 5 (25%) of 20 hospitalized patients infected with seasonal influenza A who had chest X-rays had abnormal findings while all 10 who had chest CT had abnormal findings. Hospitalized patients infected with 2009 pandemic influenza A (H1N1) were more likely to have abnormal chest X-rays than patients infected with seasonal influenza A (p = 0.02) ( Table 4) . 