Does the 1918 pandemic offer any clues to the release of COVID-19?
By JULIA FELTON and JEFF HIMLER, Tribune-Revue
PITTSBURGH (AP) – Karen Baldridge rolled up her sleeve to get her covid-19 booster shot.
“I try to make babies and (I do) whatever I can to stay healthy,” she said last week while at Excela Square in Norwin. “I think there’s about a 90% chance that I won’t get (Covid), but if I get it I don’t think I’ll get it that bad and I don’t think it will last too long time. “
Baldridge, a North Huntingdon resident in her 60s, is among the 56% of people in the United States who are fully vaccinated against covid. In Pennsylvania, it is part of nearly 58% of the total population and nearly 69% of people 18 years of age or older who are fully vaccinated, according to the Centers for Disease Control and Prevention.
Vaccines have been hailed by the medical community as society’s fastest and safest path out of the COVID-19 pandemic. Their availability is arguably the biggest difference between today’s pandemic and the influenza pandemic of 1918.
This historic event, some medical experts say, may help frame the current event – and offer clues as to where COVID-19 may be heading.
The United States recently passed the death toll from what has become the Spanish flu pandemic – a mark unthinkable 18 months ago. The United States eclipsed 700,000 deaths on Friday and there have been an estimated 4.8 million covid deaths worldwide, according to the Johns Hopkins Coronavirus Resource Center.
The 1918 pandemic killed at least 675,000 lives nationwide and 50 million worldwide, according to the Centers for Disease Control and Prevention. The United States, however, has tripled its population over the past century.
“We are 100 years later than we were then,” said Dr Nate Shively, infectious disease expert at Allegheny Health Network. “I think many would find this somewhat disheartening, just for the pandemic to continue to burn despite the fact that we really have all the tools at our disposal now to put a stop to it. And we just don’t use all of these tools effectively.
Medical experts cite the vaccine as the most effective tool. The Pfizer recall was recently approved by the Food and Drug Administration and the Centers for Disease Control and Prevention to extend protection to Americans who are older or have underlying health conditions.
Yet many remain skeptical.
Dr Amesh Adalja, a Pittsburgh-based infectious disease expert and principal investigator at the John Hopkins Center for Health Security, called it “inexcusable” that the total number of deaths from covid-19 in the United States has eclipsed that of the pandemic from 1918.
When people died of the flu in 1918, they did not have access to today’s vaccines and modern science. With the significant medical advancements made over the past 100 years, Adalja said, America should better manage this pandemic.
“What we do in the United States is self-inflicted,” he said. “We can explain the fact that people are not receptive to science and openly challenge it.”
“Rates matter more”
Dr Donald Burke, Distinguished Professor and Former Dean of the Graduate School of Public Health at the University of Pittsburgh, is an expert in the use of computer modeling and simulation to guide public health decision making .
He said it is important to consider the death rate and not just the total number of deaths.
In Pennsylvania, COVID-19 has killed more than 29,000 people, according to the state Department of Health. Keystone state was among the hardest hit by the 1918 pandemic, which killed more than 60,000 here, according to the University of Pennsylvania.
The 1918 flu is said to have caused approximately 4,500 deaths in Pittsburgh and another 2,000 in Westmoreland County. COVID-19 deaths so far have reached 2,100 in Allegheny County and 840 in Westmoreland.
“Even though the death totals are similar, the death rates – that is, the rate per 100,000 people, or per unit of population – are now about three times lower than those for influenza,” Burke said. “Total numbers are important, but rates matter more to understanding impact. “
The 1918 influenza pandemic largely affected younger populations, with a “high proportion of deaths” among people between the ages of 18 and 30. It was unusual for the flu and particularly distressing for society, said Burke, as “the day-to-day functions of society depend more on this age group.
There is no simple definition of the end of a pandemic, said Seema Lakdawala, an associate professor who studies influenza viruses in the department of microbiology and molecular genetics at the Pitt School of Medicine.
The first U.S. cases of the 1918 pandemic were reported in March of the same year, when more than 100 soldiers at Fort Riley, Kansas fell ill, according to the CDC. This was almost a year after the United States entered World War I, with troop movements cited as a factor in the spread of the disease.
The flu remained endemic in Paris in early 1919, when the End-of-War Treaty was negotiated.
Lakdawala noted that the H1N1 virus that was responsible for the 1918 pandemic never went away and continued to kill many people every year.
It wasn’t until the 1930s that the virus was recognized as the cause. A vaccine to combat it was first recommended in 1960.
Even with vaccines, tens of thousands of Americans die from the flu each year, Lakdawala said. In 2017-18, 80,000 people died from seasonal flu, she said.
Yet Lakdawala, who is also a member of Pitt’s Center for Vaccine Research, said vaccines are the surest way to control the spread of viruses – rather than trying to achieve herd immunity through natural infection.
Beyond the risk of death, she said: “There are obviously long-term consequences of contracting the virus. We’ve now had it for over a year and we have long-term symptoms of covid, ”including adverse effects on breathing and lung function.
“As viruses replicate and spread in the population, they will evolve,” she said. “If we had a higher level of vaccination, we would have less transmission and less diversity” in the covid virus. “It’s not that it would go away, but it would definitely get slower.”
“The pandemic will subside”
Burke said he predicted the COVID-19 pandemic would end much like the flu epidemic of 1918 – turning into a seasonal virus that never really goes away.
The 1918 flu “passed through the world’s population,” he said, infecting huge areas, which acquired natural immunity – the only response at the time as vaccines were not yet a reality.
But COVID-19 vaccines are available and very effective, Burke said. Once enough people are immunized – either by contracting the disease or by being vaccinated – the pandemic will abate, he said.
Even if vaccination does not improve, Adalja said, the pandemic will continue to decline. But it will do so because people contract the virus and gain natural immunity rather than being vaccinated. With infection, however, comes the risk of death, Adalja said.
“Either way, the pandemic is going to subside because people are infected. The vaccines mitigate the impact of the pandemic, but the final common path will be the same, ”Adalja said.
That’s what happened with the 1918 flu, Burke said.
“It didn’t cause a major new pandemic again, but it did cause the seasonal flu, and it continues to mutate and evolve and cause significant disease – but never pandemic proportions,” said Burke. “I wouldn’t be surprised if covid does much the same thing. It is unlikely to go away after a year or two as there are huge areas of the world that are not immune and are not vaccinated.
“As long as there are populations on the planet who are susceptible, the virus will spread.”
A positive result of the 1918 pandemic, although it was long in coming, was the creation of the World Health Organization. Exela Latrobe’s doctor of pediatrics, Dr David Wyszomierski, who studied the previous pandemic, noted that the WHO in 1952 developed a global surveillance system to track different strains of influenza.
He said the covid virus, like the flu, “can change some of its genetic material to become more contagious or more pathological.” This has happened with the emergence of the delta variant, which has been cited in the recent increase in hospitalizations and deaths.
As another flu season approaches, Wyszomierski stressed the importance of getting a covid-19 vaccine and a flu shot for those who are eligible.
“Absolutely not spared”
It may take more than 90% of the population to acquire some form of immunity before the pandemic subsides, Shively said. Once controlled, it will likely become another of the ‘endemic coronaviruses’.
Four other coronaviruses circulate in the human population as the common cold, Burke said. COVID-19 will likely join their ranks.
“If you look at the model of molecular evolution, it looks like (coronaviruses) entered humans at least hundreds of years ago,” he said. “Maybe it happens every century or so, that a virus jumps up and enters humans, and then settles into that equilibrium.”
Yet there is still a risk of another serious pandemic, experts warn.
“We are absolutely not spared from a new pandemic, whether it is 100 years in the future or later this year before it subsides,” Shively said.
The risk of pandemics spreading is higher than ever, Burke said. As the world becomes more and more interconnected, viruses are finding it easier to travel the world – while many epidemics in the past have died on a continent or in an isolated corner of the world.
Several viruses in recent years, such as Ebola and H1N1, had the potential to cause a devastating global pandemic, Shively said. They just didn’t.
“Preparing for and learning from the next pandemic is something that we, as a country and the international community, can gain,” he said. “When another pandemic will occur is hard to say, but another pandemic will occur. We need to take action to make sure we’re ready to do it.