Column by Richard Sternberg, M. D. Diligence Called for, Now More Than Ever Again, just when it seemed we reached the point where we can go out with people and decrease our use of masks, COVID strikes back and possibly with more virulence than previous strains. The number of new strains to consider is large. New strains include BA.5.2.6, BA.4.1.9, BE.1.2, BA.4.7, BF.13 and XBB, among others. Already BA.5 and BA.4 strains have high penetrance in the U.S. The new…