(a) AO stained, (b) PI stained, and (c) merged UPM0081 infected BGM-70 cells showing green-orange fluorescence as an indicator of early (white arrowhead), intermediate (yellow arrow), and late apoptosis (blue arrow) and necrosis (white arrow) at 24 hours pi. Bar = 50 µm. (d) AO stained, (e) PI stained, and (f) merged UPM190 infected BGM-70 cells showing membrane blebbing (white arrow) and positive orange color induced by the virus at 48 hours pi as a sign of apoptosis. Bar = 50 µm. (g) AO stained, (h) PI stained, and (i) merged uninfected control BGM-70 cells showing normal unapoptotic (white arrow) and necrotic cells (yellow arrow) at 24 hours after culture. Bar = 50 µm.