2015/03/20

BBC March 18, 2015: Meet the ‘living dead’: Forensic scientists’ new weapon

In the seconds after you breathe your last breath, the living dead take over. Now that your blood no longer flows, oxygen levels within your body plummet and degrading chemical processes start up, making your tissues more acidic. Some of your bacterial inhabitants relish the change and flourish, while others die off.

The shift in your internal chemistry also attracts insects, which land on your body and creep into your orifices to lay their eggs, bringing with them their own microbial hitchhikers. Several days later, these eggs hatch, and as the larvae begin to feast on your flesh they carry with them yet more microbes – as well as antimicrobial compounds that inhibit the growth of susceptible bugs.

In other words, you might be dead, but your body is more alive than ever.

Forensic scientists are now trying to harness this “necrobiome”. They believe the bugs living upon and within you could harbour vital clues about the circumstances of your demise, and how long you’ve been dead for. And it’s not just the dead that may reveal their secrets through their bugs: microbial fingerprints might also be used in rape or sexual assault cases, to provide police with vital leads about the identity of the assailant. more