PUBLISHED DECEMBER 13, 2013
In the self-proclaimed lightning capital of the world, Johannesburg, South African researchers are conducting experiments to understand how the human body reacts to a lightning strike. Their findings could help doctors learn how to treat victims more effectively and improve education about prevention.
South Africa has about 500 deaths and thousands of injuries from lightning strikes each year. The country has a population of 50 million, while the U.S.—with 313 million people—has had only 23 deaths from lightning so far this year. Johannesburg's subtropical climate means almost daily rain showers during the summer that, combined with its high elevation, makes the city particularly vulnerable to lightning.
Scientists note that South Africa isn't alone in having a high rate of lightning strikes. India, Bangladesh, Malaysia, and other developing countries also suffer from the same problem, compounded by tropical climates, agriculture-based economies that keep people outdoors, poor infrastructure that provides minimal protection, and lack of access to education about safety. (See "Death by Lightning a Danger in Developing Countries.")
In response, the University of the Witwatersrand in Johannesburg, better known as Wits University, has had a lightning research team since the mid-1960s. But recently, the electrical engineers, anthropologists, and biomedical experts there have been really pushing the boundaries of what is known about lightning deaths and injuries.
"South Africa has known about the risks of lightning since 1973, when we introduced a 'risk analysis process' that stated exactly how dangerous lightning could be," said Andrew Dickson, an engineer with the lightning research group at Wits. "But we are still somehow accepting around 500 deaths a year."
Hoping to decrease that number, the Wits scientists are trying to show exactly what happens to the human body when hit by lightning, something that has not been well understood.
Lightning and the Body
"There is little literature on how different tissues are affected when struck by lightning," said Patrick Randolph-Quinney, a forensic anthropologist with Wits University. "It has become a routine problem with the discovery of bodies in places where a lightning strike was likely. We haven't been able to say with certainty whether or not a lightning strike was indeed the cause of death."
He added that his team has found "conclusive evidence" that lightning causes a specific pattern of cracking through the cellular structure of individual bone cells, indicating the passage of extreme levels of energy.
The pattern is different from that created by other types of electricity going through the body, he noted.
Randolph-Quinney hopes the emerging research will help forensics investigators pinpoint cause of death from lightning. That's currently a challenge, he said, because there are 17,000 unclaimed bodies in Johannesburg-area morgues each year.
When it comes to lightning injuries, there has also been little research on the mechanisms of what exactly happens to the human body when struck, other than well-established complications that can arise, such as memory loss, insomnia, and depression, said Wits electrical engineering graduate student Harry Lee.
To better understand these effects, and work out why some parts of the body are damaged more than others, Lee is comparing the electrical conductivity of 56 different human tissues.
Although the research is still in the beginning stages, Lee says he eventually expects to find dry skin to have a very low conductivity rate, which would explain why a person struck by lightning rarely has external burns.
Alternatively, he also expects to find fluid-based tissues, such as cerebrospinal fluid, mucous membranes, and the gallbladder, to have higher conductivity rates.
"This work has potential to give scientists a way to look at the complex human body in a very different way," Randolph-Quinney said. Eventually, it may help doctors treat injuries from lightning.
Improving Education
Scientific breakthroughs on lightning will be good news for South Africa, a country that has largely lacked comprehensive storm education, said Ken Nixon, an electrical engineer at Wits. "South Africa has lagged behind because, for so long, we had a pretty well-run government, but it only catered to a small portion of the population," he said.
The group is also in the midst of putting together four or five definitive lightning safety rules that will be disseminated to schools and the media in the near future.
"We have had so much [misinformation] in the past," said Estelle Trengove, an electrical engineer at Wits. "People would go around saying things like, 'Oh, well, if you are a boy, or you are wearing rubber-soled shoes, or if you are already wet, you will be safe.'"
Trengove added that many South Africans also believe that lightning is connected to witchcraft. "I know a lot of educated people who believe there are two kinds of lightning: natural and lightning sent from witches. It's not just rural people," she said.
Trengove added, "We need a couple of hard-and-fast rules that everyone, rural and urban, can understand."
While still in the brainstorming phase, some of the rules would be along the lines of "never shelter under a tree" and "when a storm approaches, shelter inside a sturdy building," she said.
"We don't live in America," Nixon added. "[The popular rule] 'when thunder roars, go indoors' isn't going to work because for many, indoors isn't a sturdy building. So the way we approach these education tactics is going to be fundamentally different."
Making a Game Out of It
To help with education efforts, two Wits engineering students have created a computer game aimed at elementary school students that teaches the fundamentals of what to do when it storms.
The multilevel, timed game includes lessons like figuring out what to do with three friends who are outdoors and only have two spots in a car. In the game, you can pass the level by putting two people in the car and making the third crouch in an open area away from trees.
Earlier this year, the game had a successful test run in a couple of primary schools in the northern suburbs of Johannesburg, according to creator Anton Dreyer.
Some children were simply given an oral presentation on lightning safety, and the others played the game. The children who played the game had better scores when presented with a test later.
"There hasn't been a proper curriculum written for 10-year-olds on storm safety," Dreyer said. "And in this day and age, I do believe educational games have their place."
Increased Awareness
The researchers also note that recent big news stories about lightning deaths have made South Africans more aware of the extent of the problem. The BBC and Global Post both reported that nine schoolchildren were struck within 24 hours in February. Five were high school cricket players, and four were girls walking in the township of Soweto. All survived, but three were critically injured.
In late November, 14 manual laborers sleeping in a tent in a historically poor coal-mining town two hours east of Johannesburg were struck by lightning. Eight perished; six were injured.
"The eight workers who were killed, their sleeping conditions were not ideal, but they weren't on a mountain or an area we would consider to be super high risk," Nixon said. "There was also no pattern as to who was killed and who was just injured. There was a person who died lying right next to someone who lived."
The deaths of the laborers have caused the South African government to investigate the living conditions of the workers. Some lightning experts say the increased awareness of lightning safety is to thank for that.
"The awareness is starting to come to a head. People here are really starting to understand the risks associated with storms," Nixon said.
Ron Holle, a research meteorologist with Vaisala, a Finnish company that makes lightning detection equipment, said about Wits, "The quality of the science they are doing is on par with fully developed parts of the world." But, he added, the team has its work cut out for it.
"When you have an agriculture-based economy and people who are spending a lot of time outside, lightning strikes will always be an issue," he said.
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