Sometimes they’ll keep the clothing, the strips of shirt or trousers that weren’t cut away and discarded by the doctors and nurses. They’ll tell and retell their story at family gatherings and online, sharing pictures and news reports of survivals like their own, or far bigger tragedies. The video of a tourist hit on a Brazilian beach, or the Texan struck dead while out running. The 65 people killed during four stormy days in Bangladesh.

Only by piecing together the bystander reports, the singed clothing and the burnt skin can survivors start to construct their own picture of the possible trajectory of the electrical current, one that can approach 200 million volts and travel at one-third of the speed of light.

In this way, Jaime Santana’s family have stitched together some of what happened one afternoon in April 2016, through his injuries, burnt clothing and, most of all, his shredded broad-brimmed straw hat. “It looks like somebody threw a cannonball through it,” says Sydney Vail, a trauma surgeon in Phoenix, Arizona, who helped care for Jaime after he arrived by ambulance. His heart had been shocked several times along the way as paramedics struggled to stabilise its rhythm.

Jaime had been horse-riding with his brother-in-law and two others in the mountains outside Phoenix, a favourite weekend pastime. Dark clouds had formed, heading in their direction, so the group had started back.

They had nearly reached the house when it happened, says Alejandro Torres, Jaime’s brother-in-law. He paces out the area involved, the landscape dotted with small creosote bushes just behind his acre of property. In the distance, the desert mountains rise, their rippled, chocolate-brown peaks against the horizon. The riders had witnessed quite a bit of lightning as they neared Alejandro’s house, enough that they had commented on the dramatic zigzags across the sky. But scarcely a drop of rain had fallen as they approached the horse corrals, several hundred feet from the back of the property.

Alejandro doesn’t think he was knocked out for long. When he regained consciousness, he was lying face down on the ground, sore all over. His horse was gone. The two other riders appeared shaken but unharmed. Alejandro went looking for Jaime, who he found on the other side of his fallen horse. Alejandro brushed against the horse’s legs as he walked passed. They felt hard, like metal, he says, punctuating his English with some Spanish.

He reached Jaime: “I see smoke coming up – that’s when I got scared.” Flames were coming off of Jaime’s chest. Three times Alejandro beat out the flames with his hands. Three times they reignited. It wasn’t until later, after a neighbour had come running from a distant property to help and the paramedics had arrived, that they began to realise what had happened – Jaime had been struck by lightning.

Justin Gauger wishes his memory of when he was struck – while fishing for trout at a lake near Flagstaff, Arizona – wasn’t so vivid. If it weren’t, he thinks, perhaps the anxiety and lingering effects of post-traumatic stress disorder wouldn’t have trailed him for so long. Even now, some three years later, when a storm moves in, the flickering flashes of light approaching, he is most comfortable sitting in his bathroom closet, monitoring its progress with an app on his phone.

An avid fisherman, Justin had initially been elated when the rain started that August afternoon. The storm had kicked up suddenly, as they often do during the summer monsoon season. Fish are more likely to bite when it’s raining, he told his wife, Rachel.

But as the rain picked up, becoming stronger and then turning into hail, his wife and daughter headed for the truck, followed later by his son. The pellets grew larger, approaching golf ball size, and really started to hurt as they pounded Justin’s head and body.

Giving up, he grabbed a nearby folding canvas chair – the charring on one corner is still visible today – and turned to head for the truck. Rachel was filming the storm from the front seat, planning to catch her husband streaking back as the hail intensified. She pulls up the video on her phone.

Initially, all that’s visible on the screen is white, a blur of hail hitting the windshield. Then a flash flickers across the screen – the only one that Rachel saw that day, the one that she believes felled her husband.

Underwear worn by Jaime Santana and socks worn by Justin Gauger when they were struck by lightning. Photograph: William LeGoullon

A crashing boom. A jolting, excruciating pain. “My whole body was just stopped – I couldn’t move any more,” Justin recalls. “The pain was … I can’t explain the pain, except to say if you’ve ever put your finger in a light socket as a kid, multiply that feeling by a gazillion throughout your entire body.

“And I saw a white light surrounding my body – it was like I was in a bubble. Everything was in slow motion. I felt like I was in a bubble for ever.”

A couple huddling under a nearby tree ran to Justin’s assistance. They later told him that he was still clutching the chair. His body was smoking. When Justin came to, he was looking up at people staring down, his ears ringing. Then he realised that he was paralysed from the waist down. “Once I figured out that I couldn’t move my legs, I started freaking out.”

Describing that day, sitting on his sofa at home, Justin draws one hand across his back, tracing the path of his burns, which at one point covered roughly a third of his body. They began near his right shoulder and extended diagonally across his torso, he says, and then continued along the outside of each leg.

He leaves and returns holding his hiking boots, tipping them to show several burn marks on the interior. Those dark, roundish spots line up with the singed areas on the socks he was wearing, and with the coin-sized burns he had on both feet, which were deep enough that he could put the tip of his finger inside. The singed markings also align with several needle-sized holes located just above the thick rubber soles of his size-13 boots. Justin’s best guess – based on reports from the nearby couple, along with the wound on his right shoulder – is that the lightning hit his upper body and then exited through his feet.

Although survivors frequently talk about entry and exit wounds, it’s difficult to figure out in retrospect precisely what path the lightning took, says Mary Ann Cooper, a retired Chicago emergency physician and long-time lightning researcher. The visible evidence of lightning’s wrath is more reflective, Cooper says, of the type of clothing a survivor had on, the coins they were carrying in their pockets and the jewellery they were wearing as the lightning flashed over them.

Lightning is responsible for more than 4,000 deaths worldwide annually – according to those documented in reports from 26 countries. (The true scope of lightning’s casualties in the more impoverished and lightning-prone areas of the world, such as central Africa, is still being calculated.) Cooper is one of a small global cadre of doctors, meteorologists, electrical engineers and others who are driven to better understand how lightning injures people, and ideally how to avoid it in the first place.

Of every 10 people hit by lightning, nine will survive to tell the tale. But they could suffer a variety of short- and long-term effects. The list is lengthy and daunting: cardiac arrest, confusion, seizures, dizziness, muscle aches, deafness, headaches, memory deficits, distractibility, personality changes and chronic pain, among others.

Many survivors have a story that they want to share. In postings online and during annual gatherings of Lightning Strike & Electric Shock Survivors International, they swap tales of their brush with nature’s brutal force. The group has convened in the mountains of the south-eastern US every spring since its first meeting was held by 13 survivors in the early 1990s. In those pre-internet days, it was far more difficult to meet other survivors coping with the headaches, memory troubles, insomnia and other effects of a lightning strike, says Steve Marshburn, the group’s founder, who has been living with symptoms since he was struck near a bank teller’s window in 1969.

For nearly 30 years, he and his wife have run the organisation – which now has nearly 2,000 members – from their North Carolina home. They nearly cancelled this year’s conference, as Marshburn, who is 72 years old, has been having some health issues. But the members wouldn’t allow it, he says, a bit proudly.

The changes in personality and mood that survivors experience, sometimes with severe bouts of depression as well, can strain families and marriages, sometimes to breaking point. Cooper likes to use the analogy that lightning rewires the brain in much the same way that an electrical shock can scramble a computer – the exterior appears unharmed, but the software within that controls its functioning is damaged.

Lightning strikes near Christmas, Florida. Photograph: Jason Weingart/Barcroft Images

Both Marshburn and Cooper credit the organisation’s very existence with saving lives – it has prevented at least 22 suicides according to Marshburn. It’s not unusual for him to field a call in the middle of the night and talk for hours with someone in dire straits. He is drained afterwards, unable to do much for the next few days. Cooper, who has attended some of these gatherings, has learned to hang back as survivors and their loved ones describe their symptoms. “I still don’t understand all of them,” she says. “A lot of times I can’t understand what’s going on with these people. And I listen and I listen and I listen.”

Despite a deep vein of sympathy for survivors, some symptoms still strain Cooper’s credulity. Some people maintain that they can detect a storm brewing long before it appears on the horizon. That’s possible, Cooper says, given their heightened sensitivity to stormy signs in the wake of their trauma. She is less open to other reports, such as those from people who say that their computer freezes when they enter a room, or that the batteries in their garage door remote control or other devices drain more quickly.

Yet, even after decades of research, Cooper and other lightning experts readily admit that there are many unresolved questions, in a field where there is little or no research funding to decipher the answers. It’s not clear, for example, why some people appear to suffer seizure-related symptoms after their lightning injury. Also, are lightning survivors more vulnerable to other health problems, such as heart conditions, later in life?

Some survivors report feeling like medical nomads as they struggle to find a doctor with even a passing familiarity with lightning-related injuries. Justin, who could move his legs within five hours of being struck, finally sought help last year at the Mayo Clinic for his cognitive frustrations.

As well as coping with post-traumatic stress disorder, Justin chafes at living with a brain that doesn’t function as fluidly as it once did. He doesn’t see how he could possibly return to the type of work he used to shoulder, leading a small team that presented legal cases and helped defend the county against property value disputes. Talking on the phone one day, sounding quite articulate, he tries to convey the struggles lurking just beneath. “My words in my head are jumbled. When I think about what I’m trying to say, it’s all jumbled up. So when it comes out, it may not sound all right.”

When someone is hit by lightning, it happens so fast that only a very tiny amount of electricity ricochets through the body. The vast majority travels around the outside in a “flashover” effect, Cooper explains.

By way of comparison, coming into contact with high-voltage electricity – via a downed wire, for example – has the potential to cause more internal injuries, since the exposure can be more prolonged. A “long” exposure might still be relatively brief – just a few seconds. But that’s sufficient time for the electricity to penetrate the skin’s surface, risking internal injuries, sometimes even cooking muscle and tissue to the extent that a hand or limb might need to be amputated.

So what causes external burns? Cooper explains that, as lightning flashes over the body, it might come into contact with sweat or raindrops on the skin’s surface. Water increases in volume when it is turned into steam, so even a small amount can create a “vapour explosion”. “It literally explodes the clothes off,” says Cooper. Sometimes the shoes, too.

However, shoes are more likely to be torn or damaged on the inside, because that’s where the heat build-up and vapour explosion occurs. “That’s it,” Cooper responds when she is told about the singed markings on Justin’s hiking boots.

Steam will interact with clothing in different ways, depending on what the clothing is made of. A leather jacket can trap the steam inside, burning the wearer’s skin. Polyester can melt, leaving just a few pieces behind, usually the stitching that once held together the seams of a shirt or a jacket that’s no longer there, says Cooper, who has seen a decent quantity of post-lightning strike relics over the years.

Along with the burn marks visible on Jaime Santana’s clothes, the cellphone he was carrying in his pocket melted, bonding to his pants. (His sister, Sara, now wishes that they had kept the phone, but they threw it away, fearful that it carried some residual lightning current – a bit paranoid, she now realises.) While Jaime’s family believes the lightning shredded his hat, causing it to expand upward and outward, Cooper is more dubious when she sees a photograph. There’s no visible singeing, she notes. And the chunk of straw could have been lost during Jaime’s tumble from the horse.

Cooper authored one of the first studies of lightning injuries, published nearly four decades ago, in which she reviewed 66 medical reports about seriously injured patients, including eight she had treated herself. Loss of consciousness was common. About one-third experienced at least some temporary paralysis in their arms or legs.

Those rates may be on the high side – Cooper points out that not all lightning patients are sufficiently injured that doctors write about their cases. Survivors do often describe temporary paralysis, like Justin suffered, or a loss of consciousness, but why it occurs is not clear.

A hat and shirt worn by Jaime Santana, and a boot worn by Justin Gauger, when they were struck by lightning. Photograph: William LeGoullon

More is understood about lightning’s ability to scramble the electrical impulses of the heart, thanks to experiments involving Australian sheep. Lightning’s massive electrical current can temporarily stun the heart, says Chris Andrews, a physician and lightning researcher at the University of Queensland in Australia. Thankfully, though, the heart possesses a natural pacemaker. Frequently, it can reset itself.

The problem is that lightning can also knock out the region of the brain that controls breathing. This doesn’t have a built-in reset, meaning that a person’s oxygen supply can become dangerously depleted. The risk then is that the heart will succumb to a second and potentially deadly arrest, Andrews says. “If someone has lived to say, ‘Yes, I was stunned [by lightning],’ it’s probable that their respiration wasn’t completely wiped out, and re-established in time to keep the heart going.”

Andrews is well suited to conducting lightning studies, having trained as an electrical engineer and as a physician. His research, looking at the impact of electrical current on sheep, is frequently credited with demonstrating how lightning’s flashover current can still inflict damage within the body. One reason sheep were chosen, Andrews says, is that they’re relatively close to humans in size. Another advantage is that the specific breed chosen doesn’t grow much wool around its head, making it similar to a human’s.

During his studies, Andrews shocked anaesthetised sheep with voltage levels roughly similar to a small lightning strike, and photographed the electricity’s path. He showed that, as lightning flashes over, the electrical current enters critical portals into the body: the eyes, the ears, the mouth. This helps explain why damage to the eyes and ears is frequently reported by survivors. They might develop cataracts, or their hearing might be permanently damaged, even after the initial post-boom ringing stops.

Particularly worrisome is that, by penetrating the ears, lightning can rapidly reach the brain region that controls breathing, Andrews says. Upon entering the body, the electricity can hitch a ride elsewhere, through the blood or the fluid surrounding the brain and the spinal cord. Once it reaches the bloodstream, Andrews says, the passage to the heart is very quick.

In Arizona, Jaime Santana survived the immediate lightning strike. The family’s beloved horse, Pelucha – from the Spanish for “stuffed animal” – did not. One possibility, the trauma surgeon Sydney Vail and others speculate, is that the 680kg (1,500lb) horse absorbed a good portion of the lightning that nearly killed his rider.

Another reason Jaime survived is that, when he was struck, the neighbour who came running – someone who the family had never met before – immediately started CPR, and continued until the paramedics arrived. At one point, Alejandro says, one of the paramedics asked the other if they should stop, as Jaime wasn’t responding. The neighbour insisted that they continue. That CPR occurred immediately is “the only reason he’s alive,” says Vail.

Lightning begins high up in the clouds, sometimes as high as 25,000 feet (7,600 metres) above the earth’s surface. As it descends toward the ground, the electricity is searching, searching, searching for something to connect with. It steps, almost stair-like, in a rapid-fire series of roughly 50 metre increments. Once lightning is 50 metres or so from the ground, it searches again, like a pendulum, in a nearby radius for “the most convenient thing to hit the fastest,” says Ron Holle, a US meteorologist and long-time lightning researcher.

Prime candidates include isolated and pointed objects: trees, utility poles, buildings and occasionally people. The entire cloud-to-ground sequence happens blindingly fast.

The popular perception is that the chance of being struck by lightning is one in a million. There’s some truth here, based on US data, if one only looks at deaths and injuries in a single year. But Holle believes that statistic is misleading. If someone lives until 80, their lifetime vulnerability increases to 1 in 13,000. Then consider that every victim knows at least 10 people well, such as friends and family. Thus any individual’s lifetime probability of being personally affected by a lightning strike is even higher: a 1 in 1,300 chance.

Holle doesn’t even like the word “struck”, saying it implies that lightning strikes hit the body directly. In fact, direct strikes are surprisingly rare. Holle, Cooper and several other prominent lightning researchers recently pooled their expertise and calculated that direct strikes are responsible for no more than 3-5% of injuries. (Still, Vail, the trauma surgeon, surmises that Jaime was directly hit, given that he was riding in the desert with no trees or other tall objects nearby.)

Justin believes that he experienced what is called a side flash or side splash, in which the lightning jumps from something that has been struck – such as a tree or telephone pole – hopscotching to a nearby object or person. Considered the second most common lightning hazard, side splashes inflict 20-30% of injuries and fatalities. By far the most common cause of injury is ground current, in which the electricity courses along the earth’s surface, ensnaring a herd of cows or a group of people sleeping in a tent or a grass-thatched hut.

What should you do if you find yourself stranded a long way from a building or car when a storm kicks up? Some guidance is available: avoid mountain peaks, tall trees or any body of water. Look for a ravine or a depression. Spread out your group, with at least 6 metres (20 feet) between each person, to reduce the risk of multiple injuries. Don’t lie down, which boosts your exposure to ground current. There’s even a recommended lightning position: crouched down, keeping the feet close together.

Still, don’t dare to ask Holle about any of these suggestions. There’s no such thing as a lightning-proof guarantee, he says more than once. “There are cases where every one of these [strategies] has led to death.” In his cubicle at the control centre of the US National Lightning Detection Network (NLDN) in Tucson – operated by Vaisala, a Finnish environmental observation company – Holle has accumulated stacks and stacks of folders filled with articles and other write-ups detailing a seemingly endless litany of lightning-related scenarios involving people or animals: deaths and injuries that have occurred in tents, or during sports competitions, or to individuals huddled beneath a golf shelter or a picnic shelter or some other type of shelter.

That word whitewashes the reality, Holle says, as so-called “shelters” can become “death traps” during a lightning storm. They provide protection from getting wet – that’s it.

On a series of large screens lining two walls of a room at NLDN’s offices, Holle can see where cloud-to-ground lightning is flashing in real time, picked up by strategically positioned sensors in the US and elsewhere. Satellite data has shown that certain regions of the world, generally those near the equator, are lightning-dense. Venezuela, Colombia, the Democratic Republic of the Congo and Pakistan all rank among the top 10 lightning hotspots.

Initially, lightning safety campaigns promoted the 30/30 rule, which relied upon individuals counting off the seconds after lightning flashed. If thunder rumbled before they reached 30, lightning was close enough to pose a threat. But there’s been a move away from that advice, for various reasons, Holle says. One is practical: it’s not always easy to figure out which rumble of thunder corresponds to which lightning flash. For simplicity’s sake, everyone from schoolchildren to their grandparents these days is advised: “When thunder roars, go indoors.”

Education isn’t the only reason lightning deaths have steadily declined in the US, Australia and other high-income regions. Housing construction has improved. Jobs have moved indoors. In the US alone, annual fatalities have fallen from more than 450 in the early 1990s to fewer than 50 in recent years.

There’s always room for improvement, though. Arizona, for example, ranks high in the US when looking at lightning deaths per state population. Holle’s theory is that people stay outside longer in the desert as the rain isn’t necessarily heavy during storms. That’s why casualties can occur, even before the storm arrives, with people dallying on their way to shelter while lightning stretches out in front of the dark clouds.

Still, people in high-income countries have it easy compared with those in regions where people have no choice but to work outside in all conditions, and lightning-safe buildings are scarce. One analysis of agricultural-related lightning deaths outside the US revealed that more than half of them occurred in India, followed by Bangladesh and the Philippines. The victims were young (early 20s for the men, early 30s for the women) and were often working in farms and paddy fields.

Cooper was hit full-force with the emotional impact of what lightning can do in Africa when she attended a 2011 lightning conference in Nepal. The presenters were arranged in alphabetical order by country, so Cooper, by then retired as an emergency physician but still doing lightning-related work, was sat between the presenters from Uganda and Zambia. Richard Tushemereirwe, the Ugandan representative, kept fussing with his slides while waiting to present.

“When he got up to give his presentation, he was almost in tears,” she recalls. “He said: ‘I found out from my research that we had 75 people die in Uganda during the last lightning season.’” And just that summer, he related, 18 students had died in a single lightning strike at a school in central Uganda.

Lightning flashes over Munich, Germany. Photograph: Marcel Kusch/AFP/Getty Images

In an email, Tushemereirwe described how the lightning protection that some schools install can create a false sense of security. A rod may be installed on the roofline of one school building, but it’s not grounded. Even worse, local residents might believe that the single rod also protects nearby buildings, wrote Tushemereirwe, who serves as senior science adviser to Uganda’s president. Nor does home provide a sanctuary when lightning laces the sky, as housing in rural regions of Africa is frequently constructed from mud and grass.

Some lightning deaths go unreported or are missed entirely. It might appear, for instance, that a fire killed an entire family. But that assumption misses a key piece of the tragedy. Sometimes it is lightning that sets the grass roof ablaze, temporarily paralysing the family members within, so they are unable to escape the flames.

On a bus trip to a banquet after Tushemereirwe’s presentation, he and Cooper got talking. It was a discussion that led to a collaboration and, in 2014, the creation of a non-profit organisation now called the African Centres for Lightning and Electromagnetics Network, with Cooper its founding director. The second country to join after Uganda was Zambia. Leaders of several others have expressed interest, Cooper says.

The organisation is trying to develop a cellphone alert system so that fishermen and others in the Lake Victoria region can report severe weather heading their way. They are starting to educate schoolteachers about lightning safety and are setting up graduate study programmes.

Another priority is Ugandan schools – frequently the most substantial structures in a given community. The first lightning-protection system was installed in a school in late 2016. Focusing on protecting children is key. Adults the world over believe they are immune, Cooper states flatly. “But if you tell them that their kids are going to get injured, they pay attention.”

Still, making headway has been an uphill climb, slowed by fundraising and installation logistics. Cooper sounded a bit weary and discouraged after her most recent trip to Uganda this spring. The country has thousands of vulnerable schools. She is now searching for deeper pockets through foundation or governmental funding. “We’ve protected three of them,” she says. “Oh my God, how will we ever be able to … ” Her voice trails off. “It’s so overwhelming, I just want to quit. I don’t see how we are ever going to be able to do this.”

After Jaime was hit, the rain that had threatened all afternoon started to fall, as Sara and Alejandro were driving to Maricopa Medical Center in Phoenix. Alejandro sat tense, holding on to his terrible knowledge. “All of this way, I was thinking, ‘He’s dead. How do I tell her?’”

When they arrived, Alejandro was told that Jaime was in surgery. Surgery? There was still hope. Jaime had arrived at the Phoenix trauma centre with an abnormal heart rhythm, bleeding in the brain, bruising to the lungs and damage to other organs, including his liver, according to Vail. Second- and third-degree burns covered nearly one-fifth of his body. Doctors put him into a chemically induced coma for nearly two weeks to allow his body to recover, with a ventilator helping him breathe.

Jaime finally returned home after five months of treatment and rehabilitation, which is continuing. “The hardest part for me is that I can’t walk,” he says from the living room of his parents’ house. The doctors have described some of Jaime’s nerves as still “dormant”, says his sister, Sara – something that they hope time and rehabilitation will mend.

“We’re living through something that we never thought in a million years would happen,” says Lucia, Jaime’s mother, reflecting on the strike and Jaime’s miraculous survival, with Sara translating. They’ve stopped asking why lightning caught him in its crosshairs that April afternoon. “We’re never going to be able to answer why,” Sara says. So now it’s time for Jaime, 31, to start thinking about “what’s next” with the new life he’s been given. The family is planning a party, with a mariachi band, to celebrate Jaime’s first year of life moving forward.

When Sara and Alejandro returned home from the hospital the day after the strike, Alejandro called to his wife from the backyard. On the railing of the round pen where they work the horses, adjacent to their corrals, a peacock was perched, his colourful feathers flowing behind. They had never seen a peacock outside a zoo in Arizona before. They kept the peacock and later found it a mate. Now a family of peacocks fills one of the corral stalls. When Sara looked up what the striking bird symbolises, the answers came back: renewal, resurrection, immortality.

This is an edited version of an article that was first published by Wellcome

on mosaicscience.com. It is republished here under a Creative Commons licence

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