CP and viral infectious disease: Mice infected with A/PR/8/34 (100 TCID50) were orally administered 1.5, 15, or 50 mg/kg of BXM bid for 5 days, starting at 120 hours p.i., and then virus titers in the lungs were determined on days 5 to 10 p.i. While the virus titers in CP-untreated mice gradually decreased after day 5 p.i. (Fig 6A), the virus titers remained > 4 log10 TCID50/mL from day 5 to 10 p.i. in CP-treated mice, indicating that the period of virus infection was prolonged in immunosuppressed mice.