Pfizer and BioNTech will test an omicron-specific version of their vaccine and a fourth shot of the original vaccine to determine the best path forward.
The descendant, known as BA.2, is spreading. The World Health Organization recommended Monday that health officials evaluate it separately from the original version of omicron, known as BA.1.
About 10 million Americans older than 50 have osteoporosis. Another 43 million people in the U.S. have low bone mass. Here are methods to counter these two ailments.