To all hypochondriacs, I'm sorry.  You can now take a test called VirScan that reveals every virus you've ever had.

This test examines the antibodies in your bloodstream and uses the information to see what viruses your body had to create these antibodies, to fend them off in the first place. Some antibodies last for decades, meaning you can confirm most of the viruses you had. Of course, not every antibody can be detected, but a good majority can be spotted, so it's a good way to look for potential problems. 

The team, headed up by biologist Stephen Elledge of Bingham and Women's Hospital in Boston and Harvard Medical School, synthetically created 100,000 diseases and added them to a single drop of blood. After this, they then examined which antibodies attached to which diseases to figure out what viruses you could have caught.

Another benefit is the chance to look at the effect of a virus on large groups of people. “You can compare groups of people—young and old or those with a disease and those without—and see whether there’s a difference in their viral histories,” Elledge commented.

We've got a way to go, as VirScan is not 100% yet, but this could be fascinating!