It was only influenza. It wasn't small pox, yellow fever or Black Death -- names and descriptions normally associated with killer pandemics, epidemics of worldly proportions. Yet when it was over, the 1918 Influenza Pandemic killed more people in less than a year than any disease has in recorded history. John M. Barry, who won numerous awards for his previous book, Rising Tide: The Great Mississippi Flood of 1927, and is currently Distinguished Visiting Scholar at Tulane University, painstakingly provides the details of this most virulent plague in his new book, The Great Influenza. In a recent phone interview, Barry discussed the incredible level of mortality of this sweeping pandemic, what caused it, and why we must prepare for the inevitability of another influenza outbreak.
Q: What makes the 1918 Influenza Pandemic the worst infectious scourge the world has ever known?
A: Simply, it's the death toll. The best-researched numbers come from a Nobel laureate, (Sir) Frank Macfarlane Burnet, who lived through the pandemic and studied influenza most of his scientific life. In the 1940s, he estimated at least 50 million dead and possibly 100 million from it. A fairly recent epidemiological study has pretty much confirmed his earlier findings. And that's in a world with a total population of only 28 percent of what it is today. So if you adjust for population growth, you're talking 175 to 325 million people. More than half of them died in a couple of months. Even in absolute numbers in a world less than a third of today's size, more people died in 24 weeks from influenza than have died from AIDS in the last 24 years.
Q: What caused it?
A: A virus. All influenza viruses are normally carried in birds. However, it is one of the most quickly mutating viruses, which makes it possible to jump species. Periodically, a new influenza virus jumps from birds to man, either directly or indirectly through another animal like a pig. In this case, the virus probably jumped directly from bird to man. No one's immune system had ever seen anything like this, so it marched unimpeded into the lungs. The elderly were the exception because, as the hypothesis goes, there was a similar virus, although much less deadly, 60 years prior, so they were immune to the 1918 virus.
Q: Where does influenza attack the body? How is this different from bacterial infections?
A: It attacks cells that line the respiratory tract all the way into the inner recesses of the lungs. It differs from bacterial infections in that it is much more explosive and moves much faster. Bacteria grow in colonies and create problems by obstruction; influenza viruses destroy human cells. That doesn't mean that bacteria can't kill; of course they can.
Q: Globally, how far-reaching was the pandemic?
A: I don't believe there was any place in the world that escaped it with the exception of a couple of places that knew what it was and were capable of walling themselves off. Like American Samoa. Western Samoa lost 22 percent of its population, but American Samoa, a few miles across the Pacific Ocean from Western Samoa, quarantined itself and didn't suffer a single fatality. Fairbanks, Alaska, wouldn't allow anyone into the city and so it was unscathed. But those were exceptions.
In some African villages, people who had
been abroad would return to the village and find no one alive. That's one
reason the death toll has gone up. The "more than 20 million" that is often
reported by newspapers is technically accurate, but it's a contemporary estimate
that was done in 1927. It's reasonably accurate for Europe and the United
States; it way understates the then largely unknown world.
Q: What was it like in the United States?
A: It was pretty bad -- 675,000 people died and most of them died in a 12-week period. Again, adjusting for population growth, you're talking 1.75 million.
Q: In the book, you devote a number of pages to the horrible conditions in Philadelphia. Was it that different than other U.S. cities?
A: No, Philadelphia was not atypical. It was not the worst-hit city statistically. In fact, New Orleans was in the top 10. The cities that got hit early tended to get it the worst, and New Orleans was one of the first with the virus arriving on the steamer, Harold Walker, from Boston. However, the most striking fact -- I know this occurred in Philadelphia and I believe it happened elsewhere -- was that priests were driving horse-drawn carts down the streets calling upon people to bring out their dead.
Q: Some will say that due to the advances of medical science this couldn't happen today. How do you respond to that?
A: Of course it could. That's why they're
killing 75 million chickens right now in Vietnam, Cambodia and Thailand. This
new virus that surfaced in Hong Kong in 1997 killed six of 18 people it infected.
As a result, they slaughtered over a million chickens and totally revamped
the way they sold poultry in the markets in Hong Kong, but they didn't kill
off the virus. If that virus adapts to man, and in 1918 it looks as if the
virus adapted to man without going through another species, you will have 1918
all over again. (Editor's note: Shortly after this interview was conducted,
news reports that two cats in Thailand had contracted the "bird flu" prompted
the World Health Organization to release a statement saying that the risk to
humans is not enhanced.)
There is no vaccine right now. There was a vaccine in 1997, but the virus has mutated enough so that vaccine doesn't work. So if the virus were to jump, first it takes several months to develop the vaccine, then you have to manufacture, distribute, and administer hundreds of millions, if not several billion, doses. You would be in the deadliest race in human history if that were to happen.
Q: What about after you've contracted the influenza? Are there any drugs for that?
A: There are antiviral drugs that do work. They don't stop it cold, but they do have an impact on it. We need to stockpile these anti-influenza drugs.
Q: In your book, you describe the virus as
a "mutant swarm," a
frightening description. Why is the name so fitting? A: It's a term used by virologists to describe several viruses of which influenza is one. In a sense the virus does swarm; a single infected cell when it explodes will expel between 100,000 and a million viruses. These will include every possible permutation of that virus' genetic code. Therefore, it's a swarm, but of those expelled viruses, 99 percent have mutated to the point that they can't survive, replicate or invade another cell. But 1 percent is still alive and that is between 1,000 and 10,000 viruses that can infect other cells. Again, they include nearly every permutation possible of that genetic makeup. That's why they're capable -- a single base pair of that genetic code -- of becoming a virus that can pass from person to person. That's why it's so dangerous and that's why they're killing chickens.
Q: What safeguards do we have in place today to watch out for such a pandemic?
A: WHO, the World Health Organization, has the monitoring system, but it has enormous gaps. It includes less than half of the countries of the world. China is part of the system, but large parts of it aren't covered. Only a few parts of Africa are included and only a few parts of South America. The CDC (Centers for Disease Control) here in the U.S. works in conjunction with the WHO.
Q: Most recently with the SARS outbreak, it seems that we're bombarded with information about infectious disease and mortality rates. Doesn't this alarm the public unnecessarily? How much do we really need to know? A: I think there are two lessons from a public health perspective to be taken from the 1918 pandemic. Number one, take influenza seriously, and number two, inform the public fully. The more the people are informed, the less panic is going to erupt. If you start giving out full information, people will have it when they need it.
Q: In the aftermath of 9/11 and other terrorist attacks, what are the chances that influenza could be used as a terrorist weapon?
A: In theory, it's possible, but it would be a doomsday machine. I suppose you could get a group of mad scientists who could vaccinate themselves and then unleash it on the world. It would kill everybody. For instance, if an Islamic terrorist used it, it wouldn't just kill the West; it would destroy the Islamic world as well. If a Christian terrorist employed it, it would kill the Christian world. In theory, if they understood what makes it lethal, and they don't know this now, yes, someone could design an influenza virus to do that.
Q: What is the likelihood of such a pandemic occurring again?
A: It's inevitable that pandemics continue to occur, but whether or not one will be as deadly as 1918 remains to be seen. There was one in 1957, but it wasn't anything like 1918. The 1968 pandemic killed no more than the normal flu season although it had a much higher morbidity rate, so it had a high economic impact with so many people staying home and out of work. They don't all kill like the one in 1918.
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Author John Barry says there are two lessons to learn from the 1918 pandemic: take influenza seriously and inform the public fully.