Why Elderly Didn't Get Swine Flu

The elderly are normally the most susceptible to flu viruses, so it was something of a shock to find that they were largely spared in the recent waves of pandemic H1N1 influenza. Experts have speculated that their apparent resistance to the virus may have arisen because they were exposed to a similar virus in the past and developed some antibodies that protected them. Two new studies released recently demonstrate that this is the case, and that the virus they had been exposed to was the one that caused the 1918 " Spanish flu" pandemic that killed millions worldwide.

Thomas H. Maugh II

May 7, 2010