Should you wait for the Omicron booster? Why experts say you should ‘get it now!’

But Thomas Campbell, an infectious disease specialist at the University of Colorado School of Medicine, said CDC data show that while two-thirds of the U.S. population has received the full course of primary doses (two shots in the case of Moderna and Pfizer’s vaccines, or one of the Johnson & Johnson vaccine), just under half of that group has gotten one booster shot.