Program Three: "Dangerous Friends and Friendly Enemies"

Dangerous Friends and Friendly Enemies (Part 6 of 10)

Dr. Stuart Levy and Dr. Fred Koster track a mystery killer from a Navajo community in New Mexico with help from Dr. C.J. Peters with the Centers for Disease Control.




{Title: Dangerous Friends & Friendly Enemies}

{Accordion tango music playing.}

Narrator, Lillian Lehman: Microbes live everywhere. Outside, and inside plants, animals, and people. They are single cell creatures. Such as protozoa, bacteria, or viruses. The huge diversity of microbes make all life on Earth possible. Microbes are the earliest life on Earth that we know. They are also the smallest of creatures. To small to be seen with the naked eye. Under the microscope, we see that they live in communities, they share space, and food. And are continuously evolving, in a finally tuned balance within their environment. {Guitar tango music playing.} Human's and microbes have evolved together. Interacting like experienced dance partners. The billions of microbes traveling around with just one person, outnumber the Earth's human population. Microbial communities on the skin vary, like life on the Earth's surface. Dry areas of the back are sparsely populated, like a desert. While under the arm, life abounds as in a tropical forest. These microbes protect us from being colonized by harmful microbes that may pass to us from other people.

Scientist, Stanley Falkow: Human life without microorganisms, just wouldn't happen. We've realy just begun to understand the real kinds of complexities that exist in this life that we have with these organisms, that inhabit use.

Narrator, Lillian Lehman: Stanley Falkow is a microbiologist at Stanford university, who has spent his career studying the relationship between bacteria and humans.

Scientist, Stanley Falkow: They are the simplest free living organisms, that we're aware of. Some live exclusively in people, some live exclusively in water, some live in the soil, some live in the sea.

Narrator, Lillian Lehman: Stanley Falkow, has a perticular facination, with bacteria. Many bacteria can move by themselves. Powered by whip like flagella, their membranes, allow food in and waste out. A Bacterium, contains all the neccisary machinery to grow, and reproduce by itself. When it reaches a certian size, it divides. Following the code provided by its DNA. Within minutes the bactierium seperates, into two complete bacteria.

Scientist, Stanley Falkow: It doesn't have a brain, but it knows where it is, in a, very accurately, by constantly measuring things like the temperature, the acidity of its environment.

Narrator, Lillian Lehman: Bacteria make up the largest number of microbes that inhabit us.

Scientist, Stanley Falkow: There are literally six or seven hundred species of organisms, that inhabit us that we know about. And they are part of what is called the normal flora.

Narrator, Lillian Lehman: Although we are sterile before birth. From that moment on, we receive friendly microbes from our mother, and other people who care for us. Microbes pass to us from the hand, mouth, and breast. Our relationship with these microbes, is reciprocal. We provide them with a home, and food, and they protect us, and provide us with nutrients, and interact with our immune systems.

Scientist, Stanley Falkow: When we leave our mothers womb our, our immune system is still fairly immature, and undeveloped. And really the first foreign things, that make invasion, if you will, of us are microorganisms. So the immune system begins to see, and sample microbes, in a way, is learning from the microbes that it sees from day one.

Narrator, Lillian Lehman: Microbes colonize our skin, and the mucus lining of our mouth, throat and digestive tract. The large intestine, has hundreds of species of microbes. They live cooperatively, digesting food, and making vitamins for us.

Scientist, Stanley Falkow: There are certainly microbes that cause infection, and disease, but there is a far greater number that are apart of us, from the day we're born, until the day we die.

Narrator, Lillian Lehman: Some microbes such as the ones that live in our digestive tract, are beneficial to our well being. Other microbes however, have been our enemies for thousands of years. Through out history, infectious diseases have wiped out huge populations, in nineteen eighteen. Over twenty million people died from an influenza virus that swept the globe. Microbial killers like HIV, can emerge when, something tips the balance, in favor of one particular microbe. Other microbes such as Ebola, the mysterious killer that surfaced in Zaire, or Legionnaires' disease. Can appear when, something changes, within our relationship with the environment. These can be the most lethal. Around the world few things are feared as much as outbreaks of diseases which kill swiftly, and can appear anywhere, anytime. Outbreaks are not random acts, they have causes. Understanding those causes is part of the bigger story of microbes, as both our friends and enemies. Dr. C.J. Petters.

Doctor, C.J. Peters: We know we are overdue for a pandemic, it may be a pandemic like the nineteen eighteen, when their were twenty million deaths. How do you face the probabilities that something might happen. That would be devastating to humanity.

{Title: A Deadly Enemy Appears}

Narrator, Lillian Lehman: On May fourteenth, nineteen ninety three, in a rural community of the Navajo Nation near Gallup, New Mexico, an unknown microbial killer swiftly claimed the life of this athlete. His fiancée also died. Within a week, four more. Dr. Stuart Levy.

Doctor, Stuart Levy: One of my attendings came to tell me that he had admitted a patient that night with a disease that he hadn't seen before.

Narrator, Lillian Lehman: Dr. Fred Koster.

Doctor, Fred Koster: We had to rule out known viral pneumonias, known bacterial sepsis, septicemic plague.

Doctor, Stuart Levy: And suddenly that patient had a cardiac arrest for no explicable reason whatsoever.

Narrator, Lillian Lehman: The mystery illness caused flu like symptoms, and acute shortness of breath. The victims died rapidly, within one or two days.

Doctor, Stuart Levy: At that stage we couldn't predict, who was going to live, and who was going to die.

Doctor, Fred Koster: And then seeing this kind of on a, not a daily basis, but once or twice a week.

Narrator, Lillian Lehman: The lab tests at the University of New Mexico Hospital, searching for the cause of the disease, were unsuccessful. Over fifty percent of the patients admitted died.

Doctor, Stuart Levy: I had come from Africa were I'd seen the devastating hemorrhagic fevers, but Marburg virus, Lassa fever, and I taught them that one day we could get such a disease in this country. We don't know what this disease is, it could kill all of us.

Doctor, Fred Koster: Having all four members, of one family come down, and two of them die with a similar illness, of course is what fueled all of this anxiety.

Narrator, Lillian Lehman: The disease spread throughout the southwest. A mother of two in Nevada. A man repairing his house in Arizona. A teenager in Colorado. The outbreak was serious enough to start a national alert, and bring in the centers for disease control.

Doctor, C.J. Peters: We got the call from the folks in the southwest, and they had reached a point where they knew they needed help. We didn't know what this was. It was totally, absolutely, unknown. We knew people were dying. We knew we had a problem, with some kind of disease that looked like an infectious disease. It had a very high mortality rate. We didn't have a clue what the actual organism was.

Narrator, Lillian Lehman: C.J. Peters is the director of the emerging pathogens department at the Centers for Disease Control, and Prevention in Atlanta. We had fifteen or twenty suspected patients, and it could have gone to thirty, forty, three hundred. I mean, you just don't know when the curve starts going up, until you can get a handle on things. We looked for absolutely everything. We looked for all the bacterial agents, the viral agents, mycoplasma, fungi, you name it.

Narrator, Lillian Lehman: Suzanne Jackson almost died.

Patient, Suzanne Jackson: They made a decision to fly me to Albuquerque. You know, I was worsening, and worsening, EMT people, um, they were terrified that I might die on the way down. They were contently monitoring everything. When I arrived, I, you know, I was not breathing on my own.

Narrator, Lillian Lehman: As a last stitch effort, doctors connected Suzanne Jackson to a heart, and lung bypass unit. It saved her life. At the C.D.C. lab scientists were testing the victim's blood and tissue samples, against all known microbial killers. The testing continued for a week. Without finding the cause for the disease. more people were hospitalized. All had flew like symptoms, acute shortness of breath, and their bodies swelled up with fluid.

Patient, Suzanne Jackson: People would come in, who could look through the window, who were my friends, and they didn't know it was me. They'd you know, 'where's Susan?' And 'oh that's, that's her'.

Narrator, Lillian Lehman: Within nineteen days, the c.D.C. identified this microbe a Hantavirus as the dangerous killer. A member of the virus family, that previously had only been known to infect humans in Asia, and Europe. A virus is the smallest of microbes, and the simplest of all living things. It causes disease accidently. Simply as a byproduct of its efforts to reproduce. Inside the cell, the virus sheds its protective coating. It must enter a living cell in order to multiply. The virus duplicates its chains of genetic material by using the host cells' chemistry. The protective coating again covers the duplicated material, by hijacking the mechanism of the cell, the virus can make a million copies in hours. Once the virus was identified as a Hanta, scientist had to figure out why it suddenly emerged in the Unitesd States.

Doctor, C.J. Peters: We had to know were the virus was coming from. Other Hantaviruses come from rodents. We didn't know about this Hantavirus, it could have come from god only knows what.

Narrator, Lillian Lehman: Dr. Ben Muneta, the grandson of a Navajo medicine man, was part of the c.D.C. Investigation. He uncovered an early clue.

Doctor, Ben Muneta: I went around the reservation to the traditional healers that I knew, and then I asked them about the knowledge of the mystery illness, and what they told me was quite astounding. I was listening to them describing the things, almost word for word, what I, we, were piecing together in our meetings with the C.D.C.

Narrator, Lillian Lehman: The medicine men described the deer mouse as a carrier of the mysterious illness. The Navajo revere, and fear the dear mouse. In their ancient creation story, this lightening fast rodent, spread the seeds of life through out the world. But according to another legend, if a deer mouse enters a Navajo dwelling and sees food lying about, it gets angry at the wastefulness, and as punishment it chooses the strongest, and finest and Navajos to die.

Doctor, Ben Muneta: The traditional healers told me that the way that the deer mouse will take a human life is that uh, through their urine, and their droppings. And the way it passes is through your eyes, or through your mouth, or through your nose.

Narrator, Lillian Lehman: In Albuquerque, C.J. Peters worked hard with a multidisciplinary team of doctors and scientists. Including biologist Terry Yates. Director of the Museum of Southwestern Biology.

Scientist, Terry Yates: Hantavirus' ran, almost assuredly, they did in South America. It's interesting that the ninety three Hantavirus outbreak actually occurred in the four corners region of the south western region of the United States. Because this is exactly the area, where we have been doing a long term ecological research on small mammals, including rodents.

Narrator, Lillian Lehman: In the late nineteen seventies, Terry Yates had begun preserving tissue samples of local rodent species, including the deer mouse. Now, knowing what to search for, they found evidence of the newly discovered Hantavirus, in even their oldest tissue samples.

Doctor, Ben Muneta: The Hantavirus outbreak had a very interesting effect on Native Americans nation wide. Because Navajo people were very reluctant to talk about these beliefs to the outside world. Because, for generations, people made fun of us for that. And, it was quite a vindication.

Narrator, Lillian Lehman: Scientists confirmed that the virus came from the droppings of deer mice, it could pass to people through air borne particles of dust. The C.D.C teams began trapping deer mice, in and around the homes of the victims.

Doctor, C.J. Peters: We could actually match the genetic signature of the virus in the person who had died, we could take the viral genes from his lung, and match those genes to that of the genes that the mouse in his own house was carrying.

Scientist, Stanley Falkow: A lot of the diseases that are most feared, by physicians at least, as being the most deadly, are those in which you have, the transmission of a virus, or a microbe that lives in an animal, to humans.

Narrator, Lillian Lehman: The deadly Hantavirus doesn't make the deer mouse sick. It may even be one of it's microbial friends.

Doctor, C.J. Peters: We know, that there must be some interaction there, or the viruses wouldn't have survived as parasites, on these rodents. So there's probably an angle where these viruses are the friends of the rodents, but their definitely our enemies though.

Narrator, Lillian Lehman: There are many examples of transmission of a virus, or microbe, from animals to humans. Plaque also comes from rodents, anthrax from cattle, in each case, something allows the microbe to expand into a new host, something in the ecosystem tips the balance.

Scientist, Terry Yates: Once it became clear that the deer mice were the reservoir species for this new Hantavirus, we hypothesized that what cause the ninety three, Hantavirus outbreak, at least in the south west, was the El Niño driving increase in plant primary productivity. Which caused more food for mice. Which caused more mice, which caused more people to come into contact with infected mice. And thus more Hanta Pulmonary syndrome.

Narrator, Lillian Lehman: Once the virus, and its source were identified, the worst of the outbreak was contained. A vigorous public education campaign, stressed avoidance of deer mice, and air borne particles from their droppings. Yet questions remain. Not least, how does Hanta kill its victims? One hypothesis is that, ironically people die as a result of the intense response of their own immune system.

Doctor, C.J. Peters: Humans seem to eliminate the virus completely, but in the process of eliminating the virus they make themselves very sick.

Narrator, Lillian Lehman: When Hantavirus is inhaled, it will infect cells, allowing it to reproduce. Inside the lungs, small air sacs are surrounded by blood vessels. Within the blood vessels, our white cells patrol, looking out for invaders. Hantavirus, seen here as black dots, infects the cells that line the blood vessels. The white cells sense the invader, push through and emit strong chemicals that inactivate the virus but also weaken the blood vessels. Plasma leaks into the air sacs. Soon, the plasma accumulates, leaving no room for oxygen.

Patient, Suzanne Jackson: The virus causes, um, the cells to loose their fluid components, so I was huge. My entire body puffed up, to like, one hundred and seventy pounds. I weigh a hundred and twelve.

Narrator, Lillian Lehman: The infection of human cells by the Hantavirus, can have a deadly outcome, but the virus doesn't gain anything, if the host dies too quickly. Before it can pass to a new host. On the contrary, it looses its home. Other microbes have learned different more sophisticated strategies.

(Transcript provided by Tyler Anderson)



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