Diphtheria: The Iditarod's Strangling Angel

There's the sting and the rage of the blizzard,
As the Arctic unleashes its gale;
There's the night falling gray at the end of the day,
And there's Death riding hard on their Trail."*

The Iditarod commemorates the 1925 "serum run" dogsled relay, carrying a precious package of antitoxin to stave off an epidemic of diphtheria in Nome, Alaska. We've lived without personal knowledge of the disease for so long that the Iditarod is just a dogsled race. Diphtheria is something so distant, so lost in the past that some parents question the need to vaccinate against it. It's time to remember not just the men and dogs who outran Death on the trail to Nome, but to remember diphtheria the way it was in 1920s America.

Diphtheria was called the "Strangling Angel" for the wing-shaped patches of whitish membrane that often formed on a child's tonsils early in the disease and for the way it suffocated them as the membrane filled their throat, crept into their larynx and lungs, and blocked their breathing. If they survived this and began to improve, there was a chance that the toxin produced by the diphtheria bacteria would paralyze their breathing or weaken and stop their heart a few days or weeks later. If it affected other muscles, the paralysis could last for months.

Emil von Behring said, "The poison excreted by the bacilli is the diphtheria bacilli's dangerous weapon against the human being, without which weapon they would be delivered over helplessly to the natural prophylactic power of the living human organism." The first Nobel Prize in Medicine was awarded to von Behring for his discovery of the bacterial toxin and how to make an anti-toxin to prevent the damage it causes. After some improvements by the bacteriologist Paul Ehrlich, commercial production of the antitoxin began in the 1890s, using horses as antitoxin factories.

"In so far as the methods of treatment were concerned, all were equally valueless. The mild and some moderately severe cases recovered under good general management. The severe cases died regardless of treatment," wrote Dr. Kerley in 1918 about the days before anti-toxin was available, when 60% of the infected children under his care died no matter what he did. Outbreaks would sweep through a neighborhood, spreading among playmates, carried home to their siblings. Quarantine was the only preventive, but the deceptively mild early stages of diphtheria made quarantine of limited value. It started out like many childhood illnesses, a slightly sore throat, a case of the sniffles. In a day or two the child would have infected the neighbors before becoming seriously ill. When a quarantine sign was tacked to the door, parents began a nervous countdown of the days until they could be sure their children had not been infected.

"Intubation should not be postponed until he becomes exhausted in the struggle for air." "Intubation", inserting a hard rubber tube down the child's throat, was a desperate treatment to prevent their suffocation if the diphtheria membrane was clogging the larynx. It lowered the death rate for these cases from near 100% to a mere 70%. After antitoxin was available, the death rate for these severe cases dropped below 20%.

"A child ill with diphtheria must be looked upon as poisoned. Antitoxin is the antidote, and every case must receive enough of the antidote to neutralize the poison." Dr. Kerley was a firm believer in using the antitoxin developed by Behring liberally, both to treat infected children and to prevent their siblings from falling ill. "If there is one thing, in addition to its great usefulness, that we have learned by the administration of antitoxin, it is the necessity of giving the agent at the earliest possible moment in the disease and of giving it in full doses."

Dr. Curtis Welch, Nome's only doctor, knew what he had to do when he diagnosed one case of diphtheria in mid-January, and realized that two recent deaths and a cluster of tonsillitis cases were probably also diphtheria. He had to give large doses of antitoxin to the children if he was to save their lives. He also knew there was too little antitoxin in Nome to treat the current cases, to treat the cases he knew he would see, or to use as a preventive. By the time he sent a telegraph asking for antitoxin six children were dead of probable diphtheria. Two days later, two more children had died, 20 children had confirmed diphtheria, and the 50 siblings of the infected children were at risk. A few adults were also infected.

If the epidemic couldn't be stopped quickly, everyone knew Nome was going to bury 70 or more diphtheria victims in the next month, out of a town of 1400 people, and hundreds more would die if it spread to the scattered villages. The certainty that hundreds would die if the antitoxin didn't reach Nome as soon as possible is what sent the mushers out into the teeth of the blizzard and across risky ice packs. The hope they could arrive in time to make a difference is what kept them going.

The antitoxin arrived in Nome Monday, February 2 at 5:30AM. The usual 20- to 25-day freight trip from Nenana had taken the dogsled relay only 5 1/2 days despite record-breaking bad weather. The antitoxin was thawed and ready to administer by noon.

The final death toll was officially 7, but Welch suspected that as many as 100 Inuit children may have died and were buried on the tundra with no records of their deaths.

Sources:
Practice of Medicine, J. C. Meakins, M.D. Published by C.V. Mosby Co., 1944
The Practice of Pediatrics 2nd ed., Charles Gilmore Kerley, Published by Saunders, 1918
A History of Pediatric Immunology, Stiehm, E Richard and Johnston, Richard B. Jr; Pediatric Research:Volume 57(3)March 2005pp 458-467
The Cruelest Miles, Salisbury, Gay and Salisbury, Laney, W. W. Norton & Company, 2003
Emil von Behring's Nobel Lecture, 1901:

* 1917, Esther Birdsall Darling (this excerpt is from a poem she wrote about a different dogsled rescue by Leonard Seppala and his team led by Togo, two of the participants in the serum run.)