Primary Source: The Race for a Spanish Flu Vaccine

The landscape for the flu vaccine was the Wild West.

Noel C. Cilker
10 min readMar 9, 2021

The Covid-19 vaccine rollout, since it started in December, 2020, has often been labeled “chaotic,” “confusing,” and “inequitable.” Lines are long to receive the vaccine and a patchwork of local rules restricts who can get it and where, and that’s if a person is lucky and tenacious enough to score an appointment. Many seniors, not familiar or comfortable with online registration sites, rely on younger relatives or friends to do it for them, or risk missing fleeting opportunities to grab a shot.

The situation is less than ideal.

And yet, there is much to be heartened by. Two drug companies, Moderna and the partnership of Pfizer and BioNTech, produced an emergency-use-approved vaccine in less than a year, something never before accomplished for an infectious disease. Each company’s vaccine is 95% effective at preventing the Covid-19 disease. Add to this Johnson and Johnson’s recently-approved single-shot vaccine, and vaccines from Britain, Russia, China and elsewhere.

Critical care nurse Sandra Lindsay receives a Covid vaccine, the first person in the United States to do so, December 14, 2020. (Northwell Health)

To understand and appreciate this medical marvel, we look to our last large-scale pandemic, the flu pandemic of 1918. Largely occurring in four waves around the world, the the flu pandemic infected an estimated 500 million people globally — one out of every three people — and killed 50 million, including 675,000 in the United States. Healthy people aged 20–40 were the hardest hit.

Medical personnel treat a flu patient in New Orleans, 1918. (U.S. Navy)

Then, as now, scientists and health experts rushed to create a vaccine to stop the carnage.

In the midst of a deadly wave, a scientist offers hope. (October 2, 1918)

Flu pandemics had hit the United States before 1918, notably in 1848–1849 and in 1889–1890, and vaccines for other illnesses had been used successfully since the early 1800s, but it wasn’t until 1892 that scientists believed they’d found the cause of the flu. German scientist Richard Pfeiffer claimed that a rod-shaped bacterium was the culprit and named it influenza bacillus. As the decades passed and the field of bacteriology progressed, other scientists began to harbor doubts, but with the pandemic crippling countries around the world, there were still enough believers in 1918 to press on with an influenza bacillus vaccine. One of those was Dr. William Park, the head bacteriologist at the New York City Health Department. In October, in the midst of the deadliest wave of the flu, the New York Times ran an exciting story about a vaccine on the horizon. It’s worth noting the lack of any standardized procedure, regulatory oversight, or anything resembling an approval process.

Dr. Royal S. Copeland, Health Commissioner of New York City, announced yesterday that Dr. William H. Park, the bacteriologist of the department, had discovered and would soon prepare for general use a vaccine that would be a preventive against Spanish influenza. This, so far as the health authorities here know, will be the first time that a vaccine has been employed to prevent influenza and so important was the discovery considered that last night the department forwarded a full report to the United States Health Service in Washington. . . .

“Dr. Park and the Department of Laboratories have been working for several days on the preparation of the vaccine,” said Dr. Copeland. “It is to be hoped that this will prevent future infection of the inoculated persons. The vaccine is now being tried out by volunteers among the laboratory workers, but I cannot say what the effects have been. Those who submitted to inoculation were so interested in the development of the vaccine that they willingly submitted themselves for this service. If the vaccine proves as successful as we hope, it will in a few days be distributed in small quantities to members of the profession.”

Dr. William H. Park, c. 1900.
New York Times, October 2, 1918.

A newspaper reports that results are up in the air. (November 30, 1918)

Most scientific instruments in the early 1900s couldn’t detect pathogens smaller than bacteria, and as a result, the belief that a bacterium was the root cause of the flu persisted. Influenza bacillus was, after all, often present in those who were sick with the flu — or “grip” in contemporary parlance — and thus the vaccine was based on a heat-killed version of it. About two months after the vaccine was publicized and tests began, the Newark Evening News sounded an optimistic but cautious tone. It also warned against politicizing the vaccine.

Although 28,000 doses of Leary-Park influenza vaccine were prepared at the City Hospital laboratory, most of which were used during the recent epidemic, it is still too early to draw conclusions about the vaccine as a protective agent, in the opinion of Dr. Richard N. Connolly, city bacteriologist. . . .

“In the cases that came under our personal observation,” writes Dr. Connolly, “we have had opportunity to note the immediate results of the injections, and the writer’s personal conviction is that the average person have no fear of the results of the vaccine. . . . Regarding the value of the vaccine as a protective agent it is too early to attempt to draw conclusions, because preventive measure can easily be made to assume any complexion that an advocate or an opponent may desire. Therefore, while theoretically and logically this remedy seems well worth an extended trial, yet [illegible] sufficient data has been collected covering a long period of time and a great number of cases, it is best to avoid positive convictions for or against the use of the vaccine.”

Newark Evening News, November 30, 1918.

Vaccines are tested in military camps. (September 29, 1918)

The military has long had a tradition of medical testing on its personnel, and with an obscenely large percentage of flu cases occurring in the ranks (the first American outbreak occurred at Camp Funston in Kansas), it seemed the perfect place to test the shots. The vaccines were effective in one sense; the Kansas City Star reported that cases of pneumonia — a common, deadly, secondary infection — decreased, but preventing the flu itself was elusive.

Vaccination with a recently discovered serum which, from tests just completed at several army camps, has been found to be an almost positive preventive of contraction of pneumonia, will be used to combat the epidemic of Spanish influenza . . .

The serum has been used to a limited extent in several camps, but no announcement had been made of its discovery pending the results of widespread tests. . . . The serum is designed primarily to prevent pneumonia, which often follows attacks of influenza and which is the cause of practically all the deaths attributed to influenza. . . .

Reports received today by Acting Surgeon General Richard show that the influenza epidemic has not yet been checked.

A colorized image shows the flu ward of Camp Funston, Kansas, March 1918. (Daily Mail)
A soldier at Love Field in Dallas has his throat sprayed, seen as a preventive measure against the flu, c. 1918. (National Archives)
Soldiers at Camp Dix gargle with salt and water, seen as a preventive measure against the flu, September 1918. (National Archives)

A soldier describes the haphazard nature of getting his shots. (1918)

Army soldier Donald McKinney Wallace, serving at the University of Connecticut, described in his diary the shots he and his fellow soldiers received. By today’s standards the experiment is hardly a controlled one.

Sunday, Sept. 29, 1918

No better this morning but saw a lot of others going out on sick call so I went over to the doctors. He gave me several different kids of pills and sent me home to go to bed. The other boys went over and took their second shot. When they got back they took us sick ones around in corner by ourselves and quaranteened the whole quarters.

Sunday, Oct. 6, 1918

We are under quaranteen and can not do a thing. Because we are shut up they did not take us over to be shot in the arm and again there are lots of the fellows sick and in the hospital. If we miss 10 days between shots we have to start all over so I guess we’ll start all over.

Donald McKinney Wallace, 1918. (Wright State University Special Collections and Archives)
Wallace describes the possibility of missing his shots, October 6, 1918. (Wright State University Special Collections and Archives)

Two scientists pivot on the vaccine. (December 13, 1918)

The vaccine developed in New York did not have the hoped-for results. Dr. Park, the New York City bacteriologist who created it, and Dr. Copeland, the New York City Health Commissioner who announced it to the Times, had to swallow their disappointment. In two New York Times articles published on the same day, the doctors admitted failure but immediately pivoted to a newer version of it.

“Health Officers Split on Influenza Scourge”

Dr. W. H. Park of the Committee on Vaccines said in his report that the disease was due to an “undetermined organism,” and the dominating variety of the organism differed according to various localities. His report condemned the indiscriminate use of “stock vaccine,” and held that the vaccine should be used only in controlled cases until its efficacy could be established. He admitted that the most generally used form of vaccine offered some protection against the secondary or more serious stages of influenza, but little against the mild form of the disease, and added that the vaccine generally had not been used until the peak of the disease, thus proving little.

“Influenza Epidemic Not Expected Here”

Dr. Copeland . . . said he was favorably impressed with the vaccine of Dr. E. C. Rosenow of the Mayo Clinic. As soon as Dr. William H. Park . . . returns from Chicago, Dr. Copeland said, he would take up with him some plan of preparing Dr. Rosenow’s vaccine, so that it may be given to the people of the city. . . .

“Almost the universal opinion of the Chicago meeting was that the ordinary vaccines, those containing simply the influenza germs, were of no value,” Dr. Copeland continued. “Dr. Rosenow’s vaccine has all the strains of the pneumonia germ, the streptococcus and the staphlococcus, as well as the influenza germ.”

Weary but hopeful civilians line up for their shots. (1918)

In 1918, anyone who developed a vaccine could release it to the public through private physicians, even though, as Dr. John M. Eyler, writes, “The medical profession had at the time no consensus on what constituted a valid vaccine trial, and it could not determine whether these vaccines did any good at all. The lack of agreed-upon standards was exacerbated by the informal editorial procedures and the absence of peer review in scientific publication in 1918.” Civilians, not knowing any of this, persuaded by news stories and advertisements, and desperate for protection, lined up for their shots.

Patients line up to receive the influenza vaccine, 1918.
Patients in Seattle line up to receive the influenza vaccine, 1918. (National Archives)
A doctor inoculates patients in Sydney, Australia, 1919.
An advertisement for Sherman’s Influenza Vaccine № 38 in the New Orleans Medical and Surgical Journal, 1918. (New Orleans Medical and Surgical Journal)
A bottle of influenza vaccine, 1919. (Museums Victoria Collections)

Uncertainty nags the scientists. (1918)

Despite the many claims of vaccine success, scientists and researchers were troubled. Further studies showed that the influenza bacillus bacterium was sometimes not found in infected people, and sometimes found in healthy ones. As more of these studies came to light, more in the medical community attacked the “Pfeiffer influenza bacillae” hypothesis. The first thoughts emerged, from the American Public Health Association, that the cause might be a virus.

. . . we know that the invading organism, contrary to Pfeiffer’s first statement that true influenza bacilli are only found in true clinical influenza, influenza-like bacilli that cannot yet be differentiated from the B. influenza by any known tests are found in many other cases than those of epidemic grip. And since the animal experiments are not yet clear and no group antibodies have yet been demonstrated, and since other observers have not found influenza bacilli in all cases diagnosed as epidemic grip, doubts have accumulated in regard to their specific action. Furthermore, after the announcement was made a short time ago that some “common colds” were probably due to a filtrable virus, it was suggested that influenza also might be due to a filtrable virus and that the influenza bacillus and the other organisms, described as the cause might be only secondary invaders. . . .

The evidence in favor of the influenza bacillus being the initiating cause of the present pandemic of “influenza” is not strong enough to constitute proof. No evidence as strong has been brought forward in favor of any other cause.

Also on the doctors’ minds was a concern that would echo over 100 years later, during the Covid pandemic:

The problem of producing immense quantities of vaccine; of determining the best dosage; the time for immunity, if any, to be established; of getting the proper controls in communities not yet infected; and above all of keeping good records and gathering and analyzing them is one of the most important and staggering of problems.

It wouldn’t be until:

- the 1930s that researchers established that the flu is caused by a virus.
- 1938 that the Food and Drug Administration began requiring new drugs to be shown safe before marketing.
- 1945 that the United States approved its first flu vaccine.

One of the first approved flu vaccines, 1945.

I am currently working on Gold in the Fire, a book about Ah Toy, the first Chinese brothel madam in gold rush San Francisco.

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Noel C. Cilker

I’m a writer, interested in history’s stories and the links between then and now.