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Vital Signs with Dr. Sanjay Gupta
Infectious Disease Outbreak Prevention Measures and Studies throughout the World Examined. Aired 2:30-3p ET
Aired December 24, 2016 - 14:30 ET
THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.
[14:30:28] DR. SANJAY GUPTA, CNN CHIEF MEDICAL CORRESPONDENT: They are known as zoonotic, diseases that can jump from animals to humans, from bats, for example, or birds, with disease names like SARS or MERS. At a time when international travel has connected the world like never before, it takes a coordinated global effort to prevent a widespread outbreak.
This is "Vital Signs." I am Dr. Sanjay Gupta.
Their titles might sound like something out of flashy novel, virus hunter, disease detectives. But don't them fool you. These men and women are doing crucial work all over the globe. Here in the United States, the Centers for Disease Control and Prevention oversee 10 global disease detection centers worldwide. Their job -- monitor viruses, help curb potential outbreaks of emerging infectious diseases. In fact they constantly monitor 30 to 40 public health threats every day.
One of these centers is in South Africa where CNN's David McKenzie met up with the team in the field for a closer look at the depth they go literally to do their job.
GUPTA: It is a slow and cumbersome descent hindered by head to toe protective suits and respirators. But these are the only things standing between safety and exposure.
DAVID MCKENZIE, CNN CORRESPONDENT: So we are heading into the depths of the earth in the cave. And the aim is to find one of three bat species that could pose a threat, a viral threat.
GUPTA: In this cave are thousands of bats, any number of which could contain deadly pathogens.
MCKENZIE: So what are we seeing here?
WANDA MARKOTTER, UNIVERSITY OF PRETORIA: This is the long fingered bat.
MCKENZIE: And these are insects.
MARKOTTER: They are in these huge amounts in large colonies in South Africa.
MCKENZIE: There are a lot of bats here.
GUPTA: These are researchers with the University of Pretoria, and they are virus hunters. Their job, catch bats to catch diseases before they transfer to humans.
MARKOTTER: So this is mineoptis (ph) natalensis (ph). And the reason, the common name is the long fingered bat, because these four arms are so long. If you can stretch the wing.
MARKOTTER: This is a male.
MCKENZIE: Why could these bats pose a threat?
MARKOTTER: So this specific species has been implicated in some of the rabies related viruses. They have high population densities. And people that go into caves get in contact with them. But the other thing is that also they are with a lot of other species that gets more into contact with humans. So they can also transfer pathogens to other species of bats.
GUPTA: Something that might surprise you is where this is taking place. This is not some remote cave. We are only miles away from the city of Johannesburg, a heavily populated urban area.
MCKENZIE: This looks almost quote, but not this specific species but bats in general harbor zoonotic diseases.
MARKOTTER: They run in the species. And I think unfortunately they have been implicated quite a bit, and there are different reasons for that. They're 20 percent of all mammals. They are a huge group. Not just this bat. There are 1,240 species almost worldwide. And so they represent a big group of mammals. That's why they probably find a lot of viruses in them. But there is not a lot of research of how many of those pathogens actually made people sick or make animals sick. Even with Ebola there is not a direct link between the human outbreaks from the bats. We see some evidence in the bats and we see human outbreaks, but we can't say that bat caused the human outbreak. So a lot is still unknown, yes.
GUPTA: A lot still unknown and a lot to keep track of.
DR. JORDAN TAPPERO, DIRECTOR, CDC GLOBAL HEALTH PROTECTION CENTER: If we look over here, you can see the global disease detection operation center. And that shows where we are tracking infectious disease threats.
GUPTA: That's why having a central command center is critical for this type of work, and you'll find it at the Centers for Disease Control and Prevention headquarters in Atlanta, Georgia. Dr. Jordan Tappero is the director of the global health protection center here at CDC.
[14:35:04] TAPPERO: Only about 30 percent of countries even self- report that they are able to prevent, detect, and respond to infections disease outbreaks, and that's through the international health regulations. And so we are working around the world to try and improve capacity so that we have partners everywhere to respond quickly.
GUPTA: But within this organization, how many threats, if you will, are being assessed, evaluated?
TAPPERO: One of the things we have in our division is the Global Disease Detection Operation Center or GDD op center. Let's just use, for example, the 24-month period that were activated for the Ebola response here in the emergency operations center. During that time we were tracking almost 300 infectious disease outbreaks of concern in 145 countries. Many of them because of that communication with our partners, ministries of health, WHO, animal health organizations, were able to be thwarted. Some of them have taken a bigger response.
GUPTA: That's a huge number, 300 potential disease outbreaks in 145 countries, just about every country on the globe. Do you have enough resources? What does it take to be able to stay on top of all that?
TAPPERO: That's a very good question. To start off, those 300 outbreaks that I just mentioned in 145 countries, that's just ones that we're critically monitoring. We have had over 1,700 outbreaks we have participated in over the last six years alone. Those are more common outbreaks that we don't raise to that threat. We are really monitoring every day.
GUPTA: That monitoring starts with teams on the ground in caves like this one.
MCKENZIE: So they have to crawl through the narrow portions into the different chambers because in each chamber, there could be a different type of bat which could have different viruses.
GUPTA: Each of these bats has the potential to carry rabies, perhaps even Ebola, some of the planets deadliest but least understood viruses.
MCKENZIE: Do you ever get nervous doing this work?
MARKOTTER: The risk is really low. It probably looks scary from what we're wearing, but the risk is really. These bats that we just caught were flying around. So they are probably healthy. So we will probably look for antibodies that can just show they have been exposed.
MCKENZIE: Why is it important to do this work for public health?
MARKOTTER: So if you don't know what's in the animals, you won't be able to identify human outbreak quickly. Most of the time, we only respond when there are a lot of humans. We don't know where the virus and the pathogens came from. So if we know what's in the population we can actually tell people beforehand to be careful. And if we know how it transmits, through urine or feces or a bite, then you can actually make public recommendations about it. Otherwise, you just react when there are already a lot of people dead like we do in the Ebola outbreak.
WHITFIELD: Back on the surface, a makeshift lab is set up right outside the entrance to the cave. Samples are collected from the bat's fur, mouth, and wings, everything meticulously recorded. With the samples now from the bat cave, it's time to move on to the next location.
Next, David and the team are heading to a horse farm near Johannesburg where tiny mosquitos threaten the health of these large animals and also serve as an early warning system for humans.
[14:41:58] GUPTA: Gail Foxcroft is a professional show jumper in South Africa. Her horses are more than just prize-winning investments, they are part of the family.
GAIL FOXCROFT, SHOW JUMPER: You are asking so much of the horses. You are asking them to do stuff for you. It is not about force. It really is a partnership. You are asking them to really, huge athletic endeavor that you ask from them. And the more they work with you, the easier it is and the more likely you are to succeed.
MCKENZIE: So when her champion horse, Lindenburg (ph), became sick, it was devastating.
FOXCROFT: He couldn't put weight on his front feet. So we thought it was just an inflammatory disease. Then he started to get really shaky and eventually he sat down. Obviously it is all neurological symptoms. And then eventually he laid down and we couldn't get him up. He just actually could not stand up.
MCKENZIE: Were you trying to lift him up?
FOXCROFT: Yes. We tried to do everything with him. He couldn't stand up. As I said, he could still lift his head. He couldn't breathe properly so he had to have a tracheotomy.
MCKENZIE: The neurological symptoms became so bad Gail made the painful decision to put Lindenburg (ph) down. But the symptoms didn't line up with the original diagnosis. It was eventually determine that Lindenburg (ph) he had Shuni virus, one of the first cases here.
FOXCROFT: I think that was the biggest thing that we needed to know, yet another virus out there we had to be careful of and we had to vaccinate for.
GUPTA: Like West Nile and Zika, Shuni virus is transmitted by mosquitoes. So now Gail invites researchers to her horse farm to trap and test the insects.
FOXCROFT: Last year they found a huge number of the mosquito that carries the West Nile, but they didn't find any of the virus in the mosquitos. We need to know how to control it, what steps we take and, eventually, hopefully, how to combat the disease, because it is something that has a huge mortality rate. GUPTA: It is all part of the disease monitoring taking place here in
South Africa, one of 10 global disease detection centers worldwide. The health of these horses is actually an early warning sign of what could be coming to humans.
MCKENZIE: Why is it important to have an early warning system?
MARIETJIE VENTER, CDC, UNIVERSITY OF PRETORIA: So it I difficult in Africa and relatively for example in the United States. When West Nile first emerged in the United States, they were dying. In Africa, they are resistant, because these viruses have been around for many years. So if we can't use it as an early system. We then look for animals with the type of signs that we know are associated with virus infections caused by these viruses.
[14:45:04] So for example, neurological symptom, if you see paralysis, if you see fever outbreaks in lots of animals and, for example, we could see they could be a fever going around or the viruses we look at in this specific study that have neurological signs in animals could be things like West Nile virus and these African virus, such as Shuni virus, for example, that also call abortion in animals.
MCKENZIE: So why do you have to keep surveying all the virus threats all the time?
VENTER: So by actually doing continuance from month to month, we can see what the seasonality of these viruses are. We can see when outbreaks happen. We have an early warning system to determine if there is an increase in virus that carries them, and then we can potentially do something about them and prevent infections in humans and animals.
GUPTA: For Gail, it is not about protecting humans, but her horses, too.
FOXCROFT: You spend years and years bringing a horse up. Apart from the commercial impact it has on you, it has all the other impacts. It is financial. You have a top competitor starting his career, and the next thing it takes years and years, a minimum of six or seven years to get a horse to the top level.
MCKENZIE: There is obviously a great tragedy you have lost your prize horse. Do you see maybe some good coming out of this research for humans as well?
FOXCROFT: Absolutely. The fact that now that medical research is here every month to take sample of things, we have to know how it is spread or what the concentration of mosquitos is in a certain area at a certain time of the year to know which are the bad times when you have to use a lot more protection all those kinds of things. It is vital. And the fact that people can get the West Nile as well, it is obviously a huge issue. So it is fantastic that they are here and we support it wholeheartedly.
GUPTA: Now that the team has samples from bats and mosquitos, it is time to visit the lab. Protective gear required again because this place houses some of the most deadliest pathogens known to man.
[14:50:39] GUPTA: In 2014, West Africa saw an unprecedented outbreak of the Ebola virus. Cases were concentrated in Guinea, Sierra Leone, Liberia. But the disease was first discovered in central Africa in 1976. The recent outbreak was this race against the deadly virus and laboratories all over the world were called to help. Imagine a workplace where some of the world's deadliest pathogens are kept. That's what these labs are working with. And it's also where Dr. Sherif Zaki thrives, a disease detective in every sense of the phrase. From anthrax to Ebola and now Zika, he has been solving the mysteries of pathogens for decades.
At the CDC headquarters in Atlanta Dr. Sherif's Zaki's lab is busy. Under these microscopes are some viruses you and I have likely never heard of and would never want to.
Given that you don't know what exactly it is that you are going to see under the microscope, how do you know to protect yourself? How can you be 100 percent sure that what you're dealing with isn't something that could make you sick?
DR. SHERIF ZAKI, CHIEF PATHOLOGIST, CDC: That's a good question. So fortunately with pathology we fix our tissues in the chemical that really kills all or most infections, so we feel comfortable dealing with it. But I think the problem or one you start worrying is when you are taking those tissues as a pathologist, an autopsy or you're collecting specimens. And that's when you have to worry about having the proper protection. But your universal protections are pretty standard. As long as you are practicing those, I don't have any concerns about it.
GUPTA: Over the last few years, Ebola was a big focus for Dr. Zaki and his team of pathologists.
When you first started looking at Ebola, could you have predicted based on anything you were seeing how widespread this outbreak would be?
ZAKI: We actually started looking at Ebola, at least myself in the mid-90s. We didn't know how much the virus spreads. If you asked me 10 or 15 years ago, I would say, no, this is not in the habit. So I would have been totally wrong. The reasons are they are the poorest borders. In 10 to 15 years, you wouldn't have the same bus routes, et cetera. Actually if you had Ebola, they would put you in the hut, give you some food and water and you would either make it or not. So it didn't travel.
But nowadays with global travels, people could be on an airplane before they become symptomatic. It is not surprising that it would get to this magnitude. But that's not hindsight. Again, I would have been wrong. I would not have predicted this would have happened.
GUPTA: These new emerging infectious diseases typically don't cause much disease in humans. We see they swap back and forth between animals and humans. Is there anything you are particularly keeping an eye on, something that's new that you are thinking, I have to keep an eye on that one?
ZAKI: There is always the unknown. You have to keep your options open in terms of something new. If anything, we have learned to expect the unexpected. There are new diseases with new twists in terms of exposure, et cetera. So I am more worried about the things that we don't know about.
GUPTA: Knowing about these viruses is the first step. Before some of these pathogens reached Dr. Zaki's lab, they come here. David McKenzie has been taking us on this journey with a team of South African virus hunters. The last stop is here, a level four bio lab in South Africa, the highest bio-security level, and the only lab of its kind on the African continent.
J.T. PAWESKA: We are working with the most dangerous pathogens known to science. And very often, the knowledge of how they are obtained is very enigmatic.
[14:55:02] So there's many questions about those viruses. But the major reason is that they are very dangerous pathogens, and often we don't have much to offer to people who are actually infected with these viruses. There are no vaccines. That's why operators have to be well-protected.
GUPTA: Researchers have to train for a year before they can step inside.
MCKENZIE: And what is so crucial about the work that is being done here for public health?
PAWESKA: What is crucial, this lab is mostly focusing on diagnostics. So we do provide diagnostic services for unusual pathogens. And this time the diagnostics can be done somewhere else. So you need this highly specialized and highly technical maps for the specimens.
GUPTA: From the field to the lab, you have to admire the bravery of these men and women, the unsung heroes working behind the scene to keep us safe from emerging diseases. In a sterile environment like a laboratory, wearing heavy hazmat and breathing through tubes, it could be easy to lose sight of the true impact here. Human lives often depend on this research and the science, so if and when the next viral outbreak happens no matter where it is, we can be ready for it.
For "Vital Signs" I'm Dr. Sanjay Gupta.