How dozens of men across Alaska (and their dogs) teamed up to save one town from a deadly outbreak
During the winter of 1924, Curtis Welch – the only doctor in Nome, a remote fishing town in northwest Alaska – started noticing something strange. More and more, the children of Nome were coming to his office with sore throats.
Initially, Welch dismissed the cases as tonsillitis or some run-of-the-mill virus – but when more kids started getting sick, with some even dying, he grew alarmed. It wasn’t until early 1925, after a three-year-old boy died just two weeks after becoming ill, that Welch realized that his worst suspicions were true. The boy – and dozens of other children in town – were infected with diphtheria.
A DEADLY BACTERIA
Diphtheria is nearly nonexistent and almost unheard of in industrialized countries today. But less than a century ago, diphtheria was a household name – one that struck fear in the heart of every parent, as it was extremely contagious and particularly deadly for children.
Diphtheria – a bacterial infection – is an ugly disease. When it strikes, the bacteria eats away at the healthy tissues in a patient’s respiratory tract, leaving behind a thick, gray membrane of dead tissue that covers the patient's nose, throat, and tonsils. Not only does this membrane make it very difficult for the patient to breathe and swallow, but as the bacteria spreads through the bloodstream, it causes serious harm to the heart and kidneys. It sometimes also results in nerve damage and paralysis. Even with treatment, diphtheria kills around 10 percent of people it infects. Young children, as well as adults over the age of 60, are especially at risk.
Welch didn’t suspect diphtheria at first. He knew the illness was incredibly contagious and reasoned that many more people would be sick – specifically, the family members of the children who had died – if there truly was an outbreak. Nevertheless, the symptoms, along with the growing number of deaths, were unmistakable. By 1925 Welch knew for certain that diphtheria had come to Nome.
In desperation, Welch tried treating an infected seven-year-old girl with some expired antitoxin – but she died just a few hours after he administered it.
AN INACCESSIBLE CURE
A vaccine for diphtheria wouldn’t be widely available until the mid-1930s and early 1940s – so an outbreak of the disease meant that each of the 10,000 inhabitants of Nome were all at serious risk.
One option was to use something called an antitoxin – a serum consisting of anti-diphtheria antibodies – to treat the patients. However, the town’s reserve of diphtheria antitoxin had expired. Welch had ordered a replacement shipment of antitoxin the previous summer – but the shipping port that was set to deliver the serum had been closed due to ice, and no new antitoxin would arrive before spring of 1925. In desperation, Welch tried treating an infected seven-year-old girl with some expired antitoxin – but she died just a few hours after he administered it.
Welch radioed for help to all the major towns in Alaska as well as the US Public Health Service in Washington, DC. His telegram read: An outbreak of diphtheria is almost inevitable here. I am in urgent need of one million units of diphtheria antitoxin. Mail is the only form of transportation.
FOUR-LEGGED HEROES
When the Alaskan Board of Health learned about the outbreak, the men rushed to devise a plan to get antitoxin to Nome. Dropping the serum in by airplane was impossible, as the available planes were unsuitable for flying during Alaska’s severe winter weather, where temperatures were routinely as cold as -50 degrees Fahrenheit.
In late January 1925, roughly 30,000 units of antitoxin were located in an Anchorage hospital and immediately delivered by train to a nearby city, Nenana, en route to Nome. Nenana was the furthest city that was reachable by rail – but unfortunately it was still more than 600 miles outside of Nome, with no transportation to make the delivery. Meanwhile, Welch had confirmed 20 total cases of diphtheria, with dozens more at high risk. Diphtheria was known for wiping out entire communities, and the entire town of Nome was in danger of suffering the same fate.
It was Mark Summer, the Board of Health superintendent, who suggested something unorthodox: Using a relay team of sled-racing dogs to deliver the antitoxin serum from Nenana to Nome. The Board quickly voted to accept Summer’s idea and set up a plan: The thousands of units of antitoxin serum would be passed along from team to team at different towns along the mail route from Nenana to Nome. When it reached a town called Nulato, a famed dogsled racer named Leonhard Seppala and his experienced team of huskies would take the serum more than 90 miles over the ice of Norton Sound, the longest and most treacherous part of the journey. Past the sound, the serum would change hands several times more before arriving in Nome.
Between January 27 and 31, the serum passed through roughly a dozen drivers and their dog sled teams, each of them carrying the serum between 20 and 50 miles to the next destination. Though each leg of the trip took less than a day, the sub-zero temperatures – sometimes as low as -85 degrees – meant that every driver and dog risked their lives. When the first driver, Bill Shannon, arrived at his checkpoint in Tolovana on January 28th, his nose was black with frostbite, and three of his dogs had died. The driver who relieved Bill Shannon, named Edgar Kalland, needed the owner of a local roadhouse to pour hot water over his hands to free them from the sled’s metal handlebar. Two more dogs from another relay team died before the serum was passed to Seppala at a town called Ungalik.
THE FINAL STRETCHES
Seppala and his team raced across the ice of the Norton Sound in the dead of night on January 31, with wind chill temperatures nearing an astonishing -90 degrees. The team traveled 84 miles in a single day before stopping to rest – and once rested, they set off again in the middle of the night through a raging winter storm. The team made it across the ice, as well as a 5,000-foot ascent up Little McKinley Mountain, to pass the serum to another driver in record time. The serum was now just 78 miles from Nome, and the death toll in town had reached 28.
The serum reached Gunnar Kaasen and his team of dogs on February 1st. Balto, Kaasen’s lead dog, guided the team heroically through a winter storm that was so severe Kaasen later reported not being able to see the dogs that were just a few feet ahead of him.
Visibility was so poor, in fact, that Kaasen ran his sled two miles past the relay point before noticing – and not wanting to lose a minute, he decided to forge on ahead rather than doubling back to deliver the serum to another driver. As they continued through the storm, the hurricane-force winds ripped past Kaasen’s sled at one point and toppled the sled – and the serum – overboard. The cylinder containing the antitoxin was left buried in the snow – and Kaasen tore off his gloves and dug through the tundra to locate it. Though it resulted in a bad case of frostbite, Kaasen eventually found the cylinder and kept driving.
Kaasen arrived at the next relay point on February 2nd, hours ahead of schedule. When he got there, however, he found the relay driver of the next team asleep. Kaasen took a risk and decided not to wake him, fearing that time would be wasted with the next driver readying his team. Kaasen, Balto, and the rest of the team forged on, driving another 25 miles before finally reaching Nome just before six in the morning. Eyewitnesses described Kaasen pulling up to the town’s bank and stumbling to the front of the sled. There, he collapsed in exhaustion, telling onlookers that Balto was “a damn fine dog.”
A LIVING LEGACY
Just a few hours after Balto’s heroic arrival in Nome, the serum had been thawed and was ready to administer to the patients with diphtheria. Amazingly, the relay team managed to complete the entire journey in just 127 hours – a world record at the time – without one serum vial damaged or destroyed. The serum shipment that arrived by dogsled – along with additional serum deliveries that followed in the next several weeks – were successful in stopping the outbreak in its tracks.
Balto and several other dogs – including Togo, the lead dog on Seppala’s team – were celebrated as local heroes after the race. Balto died in 1933, while the last of the human serum runners died in 1999 – but their legacy lives on: In early 2021, an all-female team of healthcare workers made the news by braving the Alaskan winter to deliver COVID-19 vaccines to people in rural North Alaska, traveling by bobsled and snowmobile – a heroic journey, and one that would have been unthinkable had Balto, Togo, and the 1925 sled runners not first paved the way.
Scientists Attempt to Make Human Cells Resistant to Coronaviruses and Ebola
Under the electronic microscope, the Ebola particles looked like tiny round bubbles floating inside human cells. Except these Ebola particles couldn't get free from their confinement.
They were trapped inside their bubbles, unable to release their RNA into the human cells to start replicating. These cells stopped the Ebola infection. And they did it on their own, without any medications, albeit in a petri dish of immunologist Adam Lacy-Hulbert. He studies how cells fight infections at the Benaroya Research Institute in Seattle, Washington.
These weren't just any ordinary human cells. They had a specific gene turned on—namely CD74, which typically wouldn't be on. Lacy-Hulbert's team was experimenting with turning various genes on and off to see what made cells fight viral infections better. One particular form of the CD74 gene did the trick. Normally, the Ebola particles would use the cells' own proteases—enzymes that are often called "molecular scissors" because they slice proteins—to cut the bubbles open. But CD74 produced a protein that blocked the scissors from cutting the bubbles, leaving Ebola trapped.
"When that gene turns on, it makes the protein that interferes with Ebola replication," Lacy-Hulbert says. "The protein binds to those molecular scissors and stops them from working." Even better, the protein interfered with coronaviruses too, including SARS-CoV-2, as the team published in the journal Science.
This begs the question: If one can turn on cells' viral resistance in a lab, can this be done in a human body so we that we can better fight Ebola, coronaviruses and other viral scourges?
Recent research indeed shows that our ability to fight viral infections is written in our genes. Genetic variability is at least one reason why some coronavirus-infected people don't develop symptoms while others stay on ventilators for weeks—often due to the aberrant response of their immune system, which went on overdrive to kill the pathogen. But if cells activate certain genes early in the infection, they might successfully stop viruses from replicating before the immune system spirals out of control.
"If my father who is 70 years old tests positive, I would recommend he takes interferon as early as possible."
When we talk about fighting infections, we tend to think in terms of highly specialized immune system cells—B-cells that release antibodies and T-cells that stimulate inflammatory responses, says Lacy-Hulbert. But all other cells in the body have the ability to fight infections too via different means. When cells detect the presence of a pathogen, they release interferons—small protein molecules named so because they set off a genetic chain reaction that interferes with viral replication. These molecules work as alarm signals to other cells around them. The neighboring cells transduce these signals inside themselves and turn on genes responsible for cellular defenses.
"There are at least 300 to 400 genes that are stimulated by type I interferons," says professor Jean-Laurent Casanova at Rockefeller University.
Scientists don't yet know exactly what all of these genes do, but they change the molecular behavior of the cells. "The cells go into a dramatic change and start producing hundreds of proteins that interfere with viral replication on the inside," explains Qian Zhang, a researcher at Casanova's lab. "Some block the proteins the virus needs and some physically tether the virus."
Some cells produce only small amount of interferon, enough to alert their neighbors. Others, such microphages and monocytes, whose jobs are to detect foreign invaders, produce a lot, injecting interferons into the blood to sound the alarm throughout the body. "They are professional cells so their jobs [are] to detect a viral or bacterial infection," Zhang explains.
People with impaired interferon responses are more vulnerable to infections, including influenza and coronaviruses. In two recent studies published in the journal Science, Casanova, Zhang and their colleagues found that patients who lacked a certain type of interferon had more severe Covid-19 symptoms and some died from it. The team ran a genetic comparison of blood samples from patients hospitalized with severe coronavirus cases against those with the asymptomatic infections.
They found that people with severe disease had rare variants in the 13 genes responsible for interferon production. More than three percent of them had a genetic mutation resulting in non-functioning genes. And over ten percent had an autoimmune condition, in which misguided antibodies neutralized their interferons, dampening their bodies' defenses—and these patients were predominantly men. These discoveries help explain why some young and seemingly healthy individuals require life support, while others have mild symptoms or none. The findings also offer ways of stimulating cellular resistance.
A New Frontier in the Making
The idea of making human cells genetically resistant to infections—and possibly other stressors like cancer or aging—has been considered before. It is the concept behind the Genome Project-write or GP-write project, which aims to create "ultra-safe" versions of human cells that resist a variety of pathogens by way of "recoding" or rewriting the cells' genes.
To build proteins, cells use combinations of three DNA bases called codons to represent amino acids—the proteins' building blocks. But biologists find that many of the codons are redundant so if they were removed from all genes, the human cells would still make all their proteins. However, the viruses, whose genes would still include these eliminated redundant codons, would no longer successfully be able to replicate inside human cells.
In 2016, the GP-Write team successfully reduced the number of Escherichia coli's codons from 64 to 57. Recoding genes in all human cells would be harder, but some recoded cells may be transplanted into the body, says Harvard Medical School geneticist George Church, the GP-Write core founding member.
"You can recode a subset of the body, such as all of your blood," he says. "You can also grow an organ inside a recoded pig and transplant it."
Church adds that these methods are still in stages that are too early to help us with this pandemic.
LeapsMag exclusively interviewed Church in 2019 about his latest progress with DNA recoding:
The Push for Clinical Trials
In the meantime, interferons may prove an easier medicine. Lacy-Hulbert thinks that interferon gamma might play a role in activating the CD74 gene, which gums up the molecular scissors. There also may be other ways to activate that gene. "So we are now thinking, can we develop a drug that mimics that actual activity?" he says.
Some interferons are already manufactured and used for treating certain diseases, including multiple sclerosis. Theoretically, nothing prevents doctors from prescribing interferons to Covid patients, but it must be done in the early stages of infection—to stimulate genes that trigger cellular defenses before the virus invades too many cells and before the immune systems mobilizes its big guns.
"If my father who is 70 years old tests positive, I would recommend he takes interferon as early as possible," says Zhang. But to make it a mainstream practice, doctors need clear prescription guidelines. "What would really help doctors make these decisions is clinical trials," says Casanova, so that such guidelines can be established. "We are now starting to push for clinical trials," he adds.
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
Thousands of Vaccine Volunteers Got a Dummy Shot. Should They Get the Real Deal Now?
The highly anticipated rollout of a COVID-19 vaccine poses ethical considerations: When will trial volunteers who got a placebo be vaccinated? And how will this affect the data in those trials?
It's an issue that vaccine manufacturers and study investigators are wrestling with as the Food and Drug Administration is expected to grant emergency use authorization this weekend to a vaccine developed by Pfizer and the German company BioNTech. Another vaccine, produced by Moderna, is nearing approval in the United States.
The most vulnerable—health care workers and nursing home residents—are deemed eligible to receive the initial limited supply in accordance with priority recommendations from the Centers for Disease Control and Prevention (CDC).
With health care workers constituting an estimated 20 percent of trial participants, this question also comes to the fore: "Is it now ethically imperative that we offer them the vaccine, those who have had placebo?" says William Schaffner, an infectious diseases physician at Vanderbilt University and an adviser to the CDC's immunization practices committee.
When a "gold-standard" measure becomes available, participants in the placebo group "would ordinarily be notified" of the strong public health recommendation to opt for immunization, says Johan Bester, interim assistant dean for biomedical science education and director of bioethics at the University of Nevada, Las Vegas School of Medicine.
"If a treatment or prevention exists that we know works, it is unethical to withhold it from people who would benefit from it just to answer a research question." This moral principle poses a quandary for ethicists and physicians alike, as they ponder possible paths to proceed with vaccination amid ongoing trials. Rigorous trials are double-blinded—neither the participants nor the investigators know who received the actual vaccine and who got a dummy injection.
"The intent of these trials is to follow these folks for up to two years," says Marci Drees, infection prevention officer and hospital epidemiologist for ChristianaCare in Wilmington, Delaware. At a minimum, she adds, researchers would prefer to monitor participants for six months.
"You can still follow safety over a long-term period of time without actually continuing to have a placebo group for comparison."
But in the midst of a pandemic, that may not be feasible. Prolonged exposure to the highly contagious and lethal virus could have dire consequences.
To avoid compromising the integrity of the blinded data, "there are some potentially creative solutions," Drees says. For instance, trial participants could receive the opposite of what they initially got, whether it was the vaccine or the placebo.
One factor in this decision-making process depends on when a particular trial is slated to conclude. If that time is approaching, the risk of waiting would be lower than if the trial is only halfway in progress, says Eric Lofgren, an epidemiologist at Washington State University who has studied the impact of COVID-19 in jails and at in-person sporting events.
Sometimes a study concludes earlier than the projected completion date. "All clinical trials have a data and safety monitoring board that reviews the interim results," Lofgren says. The board may halt a trial after finding evidence of harm, or when a treatment or vaccine has proven to be "sufficiently good," rendering it unethical to deprive the placebo group of its benefits.
The initial months of a trial are most crucial for assessing a vaccine's safety. Differences between the trial groups would be illuminating if fewer individuals who got the active vaccine contracted the virus and developed symptoms when compared to the placebo recipients. After that point, in vaccine-administered participants, "you can still follow safety over a long-term period of time without actually continuing to have a placebo group for comparison," says Dial Hewlett Jr., medical director for disease control at the Westchester County Department of Health in New York.
Even outside of a trial, safety is paramount and any severe side effects that occur will be closely monitored and investigated through national reporting networks. For example, regulators in the U.K. are investigating several rare but serious allergic reactions to the Pfizer vaccine given on Tuesday. The FDA has asked Pfizer to track allergic reactions in its safety monitoring plan, and some experts are proposing that Pfizer conduct a separate study of the vaccine on people with a history of severe allergies.
As the FDA eventually grants authorization to multiple vaccines, more participants are likely to leave trials and opt to be vaccinated. It is important that enough participants choose to stay in ongoing trials, says Nicole Hassoun, professor of philosophy at the State University of New York at Binghamton, where she directs the Global Health Impact program to extend medical access to the poor.
She's hopeful that younger participants and individuals without underlying medical conditions will make that determination. But the departure of too many participants at high risk for the virus would make it more difficult to evaluate the vaccine's safety and efficacy in those populations, Hassoun says, while acknowledging, "We can't have the best of both worlds."
Once a safe and effective vaccine is approved in the United States, "it would not be ethically appropriate to do placebo trials to test new vaccines."
One solution would entail allowing health care workers to exit a trial after a vaccine is approved, even though this would result in "a conundrum when the next group of people are brought forward to get the vaccine—whether they're people age 65 and older or they're essential workers, or whoever they are," says Vanderbilt physician Schaffner, who is a former board member of the Infectious Diseases Society of America. "All of a sudden, you'll have an erosion of the volunteers who are in the trial."
For now, one way or another, experts agree that current and subsequent trials should proceed. There is a compelling reason to identify additional vaccines with potentially greater effectiveness but with fewer side effects or less complex delivery methods that don't require storage at extremely low temperatures.
"Continuing with existing vaccine trials and starting others remains important," says Nir Eyal, professor and director of Rutgers University's Center for Population-Level Bioethics in New Brunswick, New Jersey. "We still need to tell how much proven vaccines block infections and how long their duration lasts. And populations around the world need vaccines that are easier to store and deliver, or simply cheaper."
But once a safe and effective vaccine is approved in the United States, "it would not be ethically appropriate to do placebo trials to test new vaccines," says bioethicist Bester at the University of Nevada, Las Vegas School of Medicine. "One possibility if a new vaccine emerges, is to test it against existing vaccines."
In a letter sent to trial volunteers in November, Pfizer and BioNTech committed to establishing "a process that would allow interested participants in the placebo group who meet the eligibility criteria for early access in their country to 'cross-over' to the vaccine group." The trial plans to continue monitoring all subjects regardless of whether people in the placebo group cross over, Pfizer said in a presentation to the FDA today. After Pfizer has collected six months of safety data, in April 2021, it plans to ask the FDA for full approval of the vaccine.
In the meantime, the company pledged to update volunteers as they obtain more input from regulatory authorities. "Thank you again for making a difference by being a part of this study," they wrote. "It is only through the efforts of volunteers like you that reaching this important milestone and developing a potential vaccine against COVID-19 is possible."
CORRECTION: An earlier version of this article mistakenly stated that the FDA would be granting emergency "approval" to the Pfizer/BioNTech vaccine, rather than "emergency use authorization." We regret the error.