The Sled Dogs that Stopped an Outbreak

Nome was a small, isolated community more than 1,000 kilometres from the nearest train station. Photo from 1916

In 1925, teams of sled dogs transported medicine to stop a diphtheria outbreak in an isolated Alaskan town.

During earlier disease outbreaks, transporting medicine posed a major hurdle. One of history's most remarkable efforts to deliver desperately needed medication to the sick was the Nome serum run of 1925.

Sometime around Christmas 1924, Curtis Welch, the local doctor in Nome, Alaska, began seeing child patients for sore throats. At first he diagnosed tonsillitis, but when children began dying, he realized he was dealing with something much more serious: diphtheria.

Diphtheria is a bacterial infection that causes a thick, leathery membrane to grow over the tonsils and throat. As the neck swells, the victim can slowly suffocate, leading the disease to be nicknamed the Strangler or the Strangling Angel.

Worst of all, diphtheria most severely affects children. While its fatality rate in adults is between five and 10 per cent, as many as 20 per cent of children infected with the illness die.

Although Nome instituted quarantine measures as soon as Welch identified diphtheria, it was too late. Locals had already been exposed to the bacteria, and the outbreak continued to grow.

Nome’s children were at the highest risk during the diphtheria outbreak, since the disease has a fatality rate of up to 20 per cent in children under five.

By mid-January 1925, there were more than 20 confirmed cases of the disease in the community, and there had been at least five deaths. With a population of 1,600 in Nome itself and 10,000 more in the surrounding area, Welch believed an epidemic was "almost inevitable."

There was, however, one ray of hope. Diphtheria could be treated with an antitoxin made from the blood of horses that had been immunized against the disease. 

An emergency call for antitoxin netted a surprise find in Anchorage. Three hundred thousand units, enough to treat 30 people, were stowed in the backroom of a storehouse. 

The only question was how to get this serum to Nome.

Nome was extremely isolated from other parts of Alaska over the winter, unreachable by sea or air. The kilometres of ice around Nome's port were impassable to ships, and the frigid air temperatures were potentially fatal to pilots in open-cockpit aircraft.

The serum could travel by train as far as Nenana, but there was only one way to take it the remaining 1,000 kilometres to Nome: dog sled.

On Jan. 27, the antitoxin arrived in Nenana, and the effort to deliver it to Nome, dubbed "the Great Race of Mercy" by newspapers, began.

Diphtheria is still treated with an antitoxin made from the blood of immunized horses. These vials of antitoxin were manufactured around 1900.

Twenty mushers — two-thirds of them Indigenous — and 160 dogs were organized into a relay. Each team would cover a section of the route and pass the serum off to the next team at a designated meeting point.

So near the Arctic Circle, the sun was above the horizon for just seven hours each day. A storm was moving in, and teams would be contending with driving snow, gale-force winds, and a wind chill as low as –65 C.

Stopping only to warm the serum so it didn't freeze, they braved life-threatening conditions to complete the run.

Some mushers arrived at exchange points with faces blackened by frostbite. One musher's hands froze to his sled's handlebar and were freed only when a roadhouse owner poured warm water over them.

Perhaps the greatest heroes of the serum run, though, were Leonhard Seppala and his team of 20 dogs. Seppala had a personal reason for joining the relay: his eight-year-old daughter, Sigrid, who, like the other children of Nome, would be at high risk of death if she were to catch diphtheria.

Champion musher Leonhard Seppala poses with six of his sled dogs in 1924 or 1925. Seppala’s lead dog Togo is on the far left, and Fritz, who led another sled team during the serum run, is on the far right.

When he set out from Nome, Seppala believed his was one of only two sled teams making the trek. The original plan was to send out one team from Nome and one from Nenana that would meet in the middle to exchange the serum, and authorities added more teams to the relay only after Seppala had already left.

Seppala's team was led by 12-year-old Siberian sled dog Togo. Although he was advanced in years and small for a sled dog, Seppala considered Togo "the best dog that ever traveled the Alaska trail" and the clear choice of lead dog for such a dangerous expedition. 

The route took Seppala's team over the most perilous part of the trail, a shortcut over the unstable sea ice on Norton Sound. 

On a previous trip, Seppala's team had been stranded on an ice floe, and Togo had leapt into the water, grabbed a rope attached to the sled, wound it around his body, and pulled the floe to shore to get his team back on land, saving their lives.

Togo began leading sled teams at just eight months old. Seppala called him an 'infant prodigy.' Photo from 1921.

During the serum run, Seppala's team crossed Norton Sound overnight. The snow was so blinding and the night so black that Seppala couldn't see the way, so he allowed Togo to guide them. 

Togo weaved between the treacherous ice floes in the darkness, bringing the team straight to the next roadhouse. The ice broke up just hours after they made it back to land.

The previous record for making the trip from Nenana to Nome by dog sled was nine days, but the serum safely reached Nome just 5½ days after it had been passed to the first musher in Nenana. The epidemic was successfully averted with no further deaths. 

The average musher in the relay covered 50 kilometres. Seppala, Togo, and their team travelled over 420 kilomtres, spending five straight days on the trail.