Flu May Be Severe, Shots Less Effective

A strain of influenza that often causes severe disease is the one seen most often so far in this flu season, health officials say. And this year’s flu vaccine may not protect against all of them. The U.S. Centers for Disease Control and Prevention (CDC) issued the alert December 3. It said that the H3N2 flu strain is found in most virus samples tested this fall. And about half of those have mutated from the strain that is included in vaccines. Shots may offer less protection against these mutated strains, the CDC said. H3 viruses were widespread during the 3 deadliest flu seasons of the last decade. The CDC said people still should get flu shots because they are the best protection available. In some cases, the CDC recommended quick use of antiviral medicines.