A San Antonio doctor says he's not concerned about the new strain of coronavirus being reported in Europe. Dr. Douglas Denham is the chief medical director of Clinical Trials of Texas, and oversaw the Pfizer and Moderna vaccine trials. Denham says all viruses have a tendency to mutate, and while the new variant seems to be more easily transmitted, it so far doesn't appear to be deadlier. He says the vaccines should work well against the new strain, and existing therapeutic drugs can be used to treat patients who contract it.