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The Hot Zone Summary

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A Terrifying True Story

Interested in a Dr.-House-like type of medical mystery based on true events?

How about if its main protagonist is the Ebola virus?

Well, then it’s time to join Richard Preston and the heroes of his story in:

The Hot Zone.

Who Should Read “The Hot Zone”? And Why?

Widely admired, The Hot Zone is one of the best and most thrilling scientific books you’ll ever have the chance of reading. So, if you are interested in these kinds of books, it should be high on your reading list.

Even if you are not—give it a go: sometimes, it feels as if you are reading a novel. And it is almost so alluring that it is unputdownable.

About Richard Preston

Richard Preston is an American journalist and bestselling scientific author, a contributor to The New Yorker ever since 1985.

He has written seven exceptional nonfiction books—First Light, American Steel, The Hot Zone, The Demon in the Freezer, The Wild Trees, Panic in Level 4, and Crisis in the Red Zone—and a well-received novel, The Cobra Event

He was also chosen to edit and complete the unfinished manuscript of Micro, Richard Crichton’s final novel.

Preston is the only nondoctor to have received the Centers for Disease Control’s Champion of Prevention Award. In addition, he has also received an award from the American Institute of Physics.

“The Hot Zone Summary”

The first major non-fiction novel, In Cold Blood, may be dealing with gory quadruple murder, but, in terms of sheer horror, it has nothing on Richard Preston’s The Hot Zone, his 1994 account of the first emergence on US soil of one of the deadliest viruses known to men: Ebola.

Its subtitle—a terrifying true story—more than suits it: enthralling, fast-paced, and exceptionally well-written, the book would have been an incomparable thriller even if it hadn’t been based on factual events.

For better or for worse, it is.

Part One: The Shadow of Mount Elgon

1980: The Marburg Virus and One Unlucky Frenchmen

It’s January 1980, and a Frenchman by the name of Charles Monet (a pseudonym) decides to visit Kitum Cave on Mount Elgon in Western Kenya, on the border with Uganda.

In case you don’t know, the Kitum Cave is one of the five “elephant caves” on Mount Elgon—all of them rich with salt, all of them frequented by these majestic creatures who go deep inside the cave to dig for salt ever since time immemorial.

Charles Monet’s decision to explore the cave, however, was a fatal mistake: a week after the visit, he started vomiting and became ill with a serious fever. He is flown to Nairobi Hospital, but already on the plane he’s in such a bad state that we’ll simply decide to skip the description.

At Nairobi Hospital, he begins to hemorrhage and gets some of his blood and vomit on his doctor, Shem Musoke. Dr. Shem Musoke is unable to do anything in Monet’s case and, before too long, Monet dies.

Unfortunately, just soon after, Dr. Musoke starts showing the same symptoms. He hemorrhages badly since his blood refuses to clot and, consequently, all of his organs begin to fail, one by one. Since now it is Dr. Musoke who needs a doctor, Dr. David Silverstein steps in.

Unlike his colleague and patient, he doesn’t particularly feel like dying, so instead of working closely with his patient, he sands a sample of his blood to two labs—in South Africa and in Atlanta, Georgia. The diagnosis is devastating: the extremely dangerous Marburg virus, a Risk Group 4 pathogen of the family Filoviridae, or filoviruses.

Everything you need to know about this family of viruses, for now, is that you don’t want to mess around with any of its members. The Marburg virus may not be as deadly as its “cousins,” but it kills 1 in 4 people.

And, oh, yes, and about its cousins: the Ebola Sudan (or Sudan virus) and the Ebola Zaire virus have some of the highest mortality rates, being twice and four times scarier than the Marburg virus!

1983: Dissecting Ebola-infected Monkeys

Strangely enough, Dr. Shem Musoke survives and doesn’t infect anyone else with the virus. His blood is then sent to many institutions all over the world so that the virus can be studied more closely. 

And that’s how it reaches the US Army Medical Research Institute of Infectious Diseases (USAMRIID), which we’ll just refer to as Institute from now on because we don’t want to be unkind toward our readers.

One of the employees at this Institute—at a Level 4 laboratory—is Major Nancy Jaax, who, just like her husband, Jerry Jaax, is a veterinarian by trade. Nancy’s job is quite simple: she (in the presence and with the help of her superior, Anthony “Tony” Johnson) is supposed to dissect monkeys who have died from the Ebola Zaire virus.

And the man who infects them with it?

Eugene “Gene” Johnson, a man obsessed with the Ebola virus pretty much to the same extent as others are not. Needless to say, Gene is infecting monkeys with Ebola not because he is some kind of sadist, but because he wants to find a cure. And since he never has, Nancy and Tony always have something to dissect on their tables.

And this is even more difficult and stressful than dissecting a frog on your biology class: even a single contact with the virus guarantees a visit of the morgue.

1987: A Danish Boy and the Secret of Kitum Cave

Four years later, Gene Johnson receives samples of blood from another man—or, rather, a boy. This time it is a deceased 10-year-old from Denmark by the name of Peter Cardinal.

The tests conclusively discover the Marburg virus inside Peter’s blood. And logic discovers something else, even more interesting: since Peter too has explored Mount Elgon’s Kitum Cave, the virus must be lurking somewhere inside it. Its direct source, however, cannot be revealed despite Gene Johnson’s massive efforts.

Meanwhile, Nancy and Jerry Jaax are promoted, both of them to lieutenant colonels. In addition, Jerry becomes the head of the Institute’s veterinary division, and Jerry becomes its chief of pathology.

Parts Two & Three: The Monkey House and Smashdown

Since the second and the third part of The Hot Zone both deal with the same case—the Reston epizootic—we’ve decided to group them under a single title.

October 1989: The Dying Monkeys

In the suburb of Reston, Washington, DC, in the autumn of 1989, a company called Hazleton Research Products installed a monkey house (the Reston Primate Quarantine Unit) inside a one-story building in a small office park. 

If you don’t know what a monkey house is, it is precisely what you might guess from its name: a place that stores imported monkeys and holds them in quarantine for a month before shipping them across the US.

One day in October, Dan Dalgard, a consulting veterinarian at the Reston Primate Quarantine Unit, noticed something strange: a large number of some newly imported monkeys started dying. By November the situation gets worse, so Dalgard contacts the Institute.

He sends some samples to two scientists, Peter Jahrling and Thomas Geisbert, who are surprised to notice, at first sight, that the cells from the samples are practically destroyed. They try to garner more information by smelling the culture, and the absence of smell suggests to them that it must be simian hemorrhagic fever—a highly pathogenic virus in monkeys, but one that is also harmless to humans.

They are, of course, wrong.

When they analyze the cells under a microscope, they discover that the cells are infected by a filovirus. Even though they fear that they have been exposed, they keep this information a secret and relay the rest to Gene Johnson and Colonel Clarence James “C. J.” Peters.

In time, the news becomes even worse: as Jahrling discovers, the virus is either the deadliest form of filovirus (Ebola Zaire) or some unknown very close relative of this virus.

Either way, it’s time to be alarmed.

So, everybody is—including the Jaaxes, Dalgard, Major General Philip K. Russell (who oversees the USAMRIID), the local authorities, the Pentagon.

December 1989: Euthanizing the Monkeys

Despite everything, Dan Dalgard is relatively calm.

However, one day, an employee of his, Jarvis Purdy, suffers a heart attack. Fearing that it might be Ebola-related, Dalgard contacts the Institute which gathers samples from Purdy and several monkey corpses. 

While Nancy is dissecting, the others (Dalgard, Johnson, C.J., General Russell) hold a meeting during which they decide it is not smart to take any more risks and agree on putting the Army in charge of euthanizing the monkeys.

The operation is conducted in secrecy so as to not alert the press or cause panic in the public. Even so, it is a dangerous one, since the monkeys in question (mostly crab-eating macaques) are not friendly toward humans and have sharp teeth. 

However, it is a necessary one, since the bodies of the monkeys dissected by Nancy are virtually destroyed, meaning the virus they are dealing with is so dangerous that euthanizing all of the monkeys is the only risk worth taking.

Case in point, an employee of the Monkey House by the name of Milton Frantig begins vomiting. As he is taken to the hospital, soldiers storm the monkey house and start killing the animals.

The operation, fortunately, runs smoothly, with only one of the monkeys escaping—but only briefly. Everything else goes according to plan.

January 1990: The Most Dangerous Strand

Soon after, tests on Milton Frantig discover that he is infected with the virus. The same is true in the case of Jarvis Purdy and two other Reston employees.

Three questions arise: 1) why didn’t the first tests show this; 2) how is it possible that all four men have remained virtually symptomless, one or two vomiting episodes aside; and 3) why aren’t other men infected by now?

Soon, all of these questions are answered, but in a rather strange and unexpected way, thanks to another group of infected monkeys who arrive at Reston soon after from the Philippines.

The Army decides to not intervene this time, leaving the monkeys to die out naturally.

What they discover is startling!

Namely, they weren’t infected before coming to Reston: they got infected afterward. How could that be when the Ebola Zaire virus is not airborne and can only be transmitted through contact and blood?

Well, it is because it was never the Ebola Zaire virus in the first place. It is a new, fourth strand of the virus now referred to as the Reston strand, the most dangerous of them all as far as monkeys are concerned. It is basically the Ebola Zaire virus plus the ability to transmit through air.

Fortunately, unlike the Ebola Zaire virus which kills 9 out of 10 infected people, for some unknown reason, the Reston strand doesn’t seem to affect humans.

Describing it, Preston writes:

Each filovirus strain contains seven proteins, four of which are completely unknown. Something slightly different about one of the Reston proteins is probably the reason the virus didn’t go off in Washington like a bonfire. The Army and the C.D.C. have never downgraded the safety status of Reston virus. It remains classified as a Level 4 hot agent, and if you want to shake hands with it, you had better be wearing a space suit. Safety experts feel that there is not enough evidence, yet, to show that the Reston strain is not an extremely dangerous virus. It may be, in fact, the most dangerous of all the filovirus sisters, because of its seeming ability to travel rather easily through the air, perhaps more easily than the others. A tiny change in its genetic code, and it might turn into a cough and take out the human race.

Part Four: Kitum Cave

Three years after the events described in the first three parts, Richard Preston decides to do something no normal man would ever want to do after reading this book, and something investigative journalists can’t help but do: visit the scenes of the crime.

Yup, Preston decides to visit both Kitum Cave and the Reston monkey house.

While traveling to Kitum, he contemplates the emergence of another virus immensely popular and frightening at the time The Hot Zone was published: HIV. According to him, it gets easier with every year for viruses to spread: one of the unexpected negative effects of globalization.

After reaching Kitum Cave, Preston is amazed at its beauty and overwhelmed by feelings incited by the fact that he has come where his story had once begun. After putting on a spacesuit, he steps inside, only to leave after a few moments, terrified that he may be infected.

“The emergence of AIDS, Ebola, and any number of other rain-forest agents appears to be a natural consequence of the ruin of the tropical biosphere,” he writes in the chilling concluding chapters, going on to say that:

In a sense, the earth is mounting an immune response against the human species. It is beginning to react to the human parasite, the flooding infection of people, the dead spots of concrete all over the planet, the cancerous rot-outs in Europe, Japan, and the United States, thick with replicating primates, the colonies enlarging and spreading and threatening to shock the biosphere with mass extinctions. Perhaps the biosphere does not ‘like’ the idea of five billion humans. Or it could also be said that the extreme amplification of the human race, which has occurred only in the past hundred years or so, has suddenly produced a very large quantity of meat, which is sitting everywhere in the biosphere and may not be able to defend itself against a life form that might want to consume it. Nature has interesting ways of balancing itself. The rain forest has its own defenses. The earth’s immune system, so to speak, has recognized the presence of the human species and is starting to kick in. The earth is attempting to rid itself of an infection by the human parasite. Perhaps AIDS is the first step in a natural process of clearance.

With thoughts such as this in his mind, Preston travels to visit the now-abandoned monkey house at Reston. Everything is back to normal there (sort of), life springing yet again inside the facility, in all kinds of forms: plants, insects, spiders.

“Ebola had risen in these rooms, flashed its colors, fed, and subsided into the forest,” writes Preston in the last two sentences of the book. “It will be back.”

Key Lessons from “The Hot Zone”

1.      You Don’t Want to Mess with Filoviruses
2.      What the Ebola Virus Does to a Human Body
3.      Viruses, the Immune System of the Earth

You Don’t Want to Mess with Filoviruses

Filoviruses are a family of viruses named so because, under a microscope, they resemble a filament, or a short thread (filo is Latin for thread).

There are a number of filoviruses, and all of them are classified as Risk Group 4 Pathogens by the World Health Organization. The four Richard Preston deals with in his book are:

Marburg virus: Named after a city in Germany where its first major outbreak killed many people at a factory in 1967; it has a mortality rate of 25% in humans;
Sudan Ebola virus: An aggressive form of Ebola whose first known outbreak killed 181 out of 284 people in Sudan in 1976; it has a mortality rate of 50% in humans;
Zaire Ebola virus: The most hostile form of the Ebola virus which kills 9 out of 10 people infected with it.
Reston virus: Discovered in Reston, USA, by accident, the Reston virus is almost the same as the Zaire Ebola virus, but though it is as lethal to monkeys, it doesn’t seem to affect humans.

What the Ebola Virus Does to a Human Body

In short, the answer to the question above is—it annihilates it. Attacking almost all types of cells, it dissolves the human tissue, practically liquifying organs and shutting down bodily functions one by one.

Since it also causes severe hemorrhages (from absolutely everywhere), many victims die due to losing too much blood. 

Interestingly enough, that may be a kind of death in the case of Ebola.

Viruses, the Immune System of the Earth

The last part of The Hot Zone is especially chilling since Richard Preston uses it to express his opinions about these viruses (including the then-discovered HIV) and delivers an accurate description, which, for once, isn’t anthropocentric.

What if—he asks—what if all these viruses (Ebola, HIV, etc.) are simply Earth’s immune system, its automatic response to the number of humans on Earth? What if, in some way or another, in the grand scheme of things, we’ve become unbearable to it? What if finding a cure for them is not what we’re supposed to be looking for?

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“The Hot Zone Quotes”

In biology, nothing is clear, everything is too complicated, everything is a mess, and just when you think you understand something, you peel off a layer and find deeper complications beneath. Nature is anything but simple. Click To Tweet To mess around with Ebola is an easy way to die. Better to work with something safer, such as anthrax. Click To Tweet When people asked him why he didn't work with those viruses, he replied, I don't particularly feel like dying. Click To Tweet The earth is attempting to rid itself of an infection by human parasite. Click To Tweet It showed a kind of obscenity you see only in nature, an obscenity so extreme that it dissolves imperceptibly into beauty. Click To Tweet

Our Critical Review

The Hot Zone has been deemed both one of the best science books ever written (American Scientist) and “a top-drawer horror story” (Newsweek).

If you don’t believe the latter, just ask Stephen King, according to whom The Hot Zone is “one of the most horrifying things” he has ever read. 

“What a remarkable piece of work,” he adds afterward, echoing precisely our very first thought after finishing the book.

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