>> this is george gao. he is the head of china's cdc. his team immediately ordered up samples from patients in wuhan. and this is the actual cct footage from his lab as they got the first look at what might be causing the new illness. this was the first clue. from these images of infected cells it was immediately clear to gao they were dealing with a virus. but which type? an electron microscope provided the first answer. it was still the first week of the new year. now gao was staring at this.