Shiloh’s ‘Angel Glow’ was lifesaver,
study won youngsters national award

Ask 17-year-old Bill Martin about a mysterious light called “Angel’s Glow” and he’ll explain how it won a national award for him and an inquisitive friend.

Bill, in 2001, visited the Shiloh battlefield with his family. While there, he learned about soldiers “glowing wounds.” He found that some of the Shiloh soldiers wounded during the April 1862 battle sat in the mud for two rainy days and nights waiting for medics to get around to them. As dusk fell the first night, some of them noticed their wounds were glowing, casting a faint light into the darkness of the battlefield.

Even stranger, when the troops were eventually moved to field hospitals, those whose wounds glowed had a better survival rate and had their wounds heal more quickly than their un-illuminated brothers-in-arms.

Bill asked his mother – a microbiologist with the U.S. Department of Agriculture – about the glowing wounds. His mom, who had studied luminescent bacteria that lived in the soil, suggested that her son conduct some experiments to determine the answer.

Young Bill and a friend, Jon Curtis, did the research and the conditions during the Battle of Shiloh. They learned that Photorhabdus luminescens live within parasitic worms called nematodes, and the two share a strange lifecycle. Nematodes hunt down insect larvae in the soil or on plant surfaces, burrow into their bodies, and take up residence in their blood vessels. There, they throw up the P. luminescens bacteria living inside them. Upon their release, the bacteria, which are bioluminescent and glow a soft blue, begin producing a number of chemicals that kill the insect host and suppress and kill all the other microorganisms already inside it.

This leaves P. luminescens and their nematode partner to feed, grow and multiply without interruptions.

In short, as the process continues, the bacteria in the wound is cleaned away.

Looking at historical records of the battle, Bill and Jon figured out that the weather and soil conditions were right for both P. luminescens and their nematode partners. Nighttime temperatures in early April would have been low enough for the soldiers who were out there in the rain for two days to get hypothermia, lowering their body temperature and giving P. luminescens a good home. It was concluded that bacteria, along with the nematodes, got into the soldiers’ wounds from the soil. This not only turned their wounds into nightlights, but may have saved their lives.

For their efforts, Bill and Jon won first place in the 2001 Intel International Science and Engineering Fair team competition.