Tuesday, April 25, 2017

Glowing Wounds at the Battle of Shiloh: The Strange Facts Behind the Legend of the Angel’s Glow

By Mark Weaver, 3-15-14

Wars breed blood and death on a massive scale. They also breed their share of strange stories. The American Civil War was no exception to this rule. Whether it was the governor who wanted to arm his troops with pikes on battlefields dominated by rifles and artillery, or the doctor who plotted to use biowarfare on Northern cities, the War Between States had its fair share of strange factual stories.

But another thing that warfare breeds is folklore. These apocryphal stories seem too good to be true. Once such bit of folklore that was largely dismissed as wishful thinking came from the Battle of Shiloh, which took place on April 6-7, 1862. The bloodiest battle up to that point in the war, two days of fighting produced 23,000 casualties on both sides. The battlefield itself was a boggy, mud soaked hellhole. Medical services on both Confederate and Union sides were woefully unprepared for the scale of the slaughter, and many wounded were left to fend for themselves among the watery morass.

When help finally managed to reach those poor souls, their rescuers noticed something odd. Their wounds gave off a faint glow in the night! Furthermore, the wounded whose injuries glowed had a better survival rate than their peers whose wounds did not. At a loss to explain what was happening, the flummoxed soldiers dubbed the strange phenomena “Angel’s Glow,” because it truly did seem to be the work of angels.

For a long while, the story was regarded as little more than folklore. That is, until seventeen year old Bill Martin heard the story, and asked his mother, Phyllis Martin, who is a microbiologist, if the bioluminescent soil bacteria she was studying, photorhabdus luminecens, might be responsible for the strange tale. She encouraged her son and his friend, John Curtis, to do further research and experiment to uncover the answer (because that’s what happens when mom is a scientist.) What they found was a remarkable explanation behind a story that was long regarded to be little more than a legend.

P. luminescens is an unlikely saviour. The bacteria hangs out in the guts of various nematode worm species, living in an odd symbiosis. The nematodes are predators of the soil, hunting down insect larva which they devour with P. luminescens’ help. The nematodes burrow into the unfortunate larva’s bloodstream, where they puke out their bacterial payload. P. luminescens releases toxins that kill the bug in short order, giving the nematode quick access to an insect buffet. These toxins also inhibit the growth of bacteria that would decompose the insect corpse, letting the germ and the worm have plenty of time to feast and multiply in their prey’s carcass.

It is this toxin that was likely responsible for helping the soldiers survive their horrific wounds. The hypothesis that Martin and Curtis developed claimed that the glowing bacteria entered soldier’s wounds when nematodes attacked the insect larva who are naturally attracted to such injuries. The resulting infestation would wipe out any of the normal, disease causing bacteria found in wounds.

The only problem with the hypothesis was that P. luminescens cannot survive at human body temperatures. The teenage scientists came up with a novel way to approach this problem.

For once, hypothermia was a good thing

Their answer lay in the muddy battlefield itself. The battle took place in early April, when temperatures were relatively low. Adding to the misery, it rained on and off throughout the battle. Injured men were left exposed to the elements for two days in some cases. By that time, hypothermia would have set in. That would have given P. luminescens time to take hold and kill off harmful bacteria. Then, when the soldiers were taken in and warmed back up, their bodies would have naturally killed off the bug. For once, hypothermia was a good thing.

With that, the teenagers managed to present a plausible explanation for the Angel’s Glow, a phenomena that was long thought to be little more than fanciful thinking by desperate men. The exact nature of the toxin the bacteria uses to perform its medical miracles has yet to be identified, but the duo are working to isolate it. Perhaps the bacteria that saved lives 150 years ago might be able to save even more today.

“Glowing Wounds.” sciencenetlinks.com. AAAS ScienceNetLinks. March 15, 2014. <http://sciencenetlinks.com/science-news/science-updates/glowing-wounds/>

Byme, James. “Photorhabdus luminescens: The Angel’s Glow.” TheNakedScientists.com. February 25, 2011. The Naked Scientists. March 15, 2014. <http://www.thenakedscientists.com/HTML/articles/article/angel-glow/>

“Shiloh.” CivilWar.Org. Civil War Trust. March 15, 2014. <http://www.civilwar.org/battlefields/shiloh.html>

Image: A false color micrograph of a soybean cyst nematode and an egg. The species that lived symbiotically with P. luminescens would have looked similar.

From: oddlyhistorical.com


Post a Comment


Facebook Twitter Delicious Stumbleupon Favorites