Friday, December 25, 2020

알려지지 않은 미지의 질병 'X'를 찾아, 경종 울린 메디칼 닥터들. Covid-19보다 더무서운 전염병 발생 걱정이다.

 아직도 Coronavirus Pandemic의 헤어나지 못하고 지구촌의 모든 인류가 고군분투하고 있기를 일년을 하고 있는데, 겨우 백신개발하여, 접종이 시작되기 시작하고 있는데, 또다른 무서운, 아직 이름도 정해지지 않은 질병이 발생할것을 염려하는 닥터의 경고가 가슴을 놀라게 한다.

아프리카 콩고공화국의 Rainforest에서 Ebola병원균을 발견한 닥터가 한번 걸리면 매우 치명적일수 있는 바이러스가 어쩌면 지금으로 부터 언제든지 발생할것을 경고하고 있어 긴장하게 만들고있다.

아프리카 콩고공화국의 수도  Kinshasa에서 멀지않은 한 타운, Ingende의 한병상에서 우두커니 앉아있는 여인은 심한 출혈과 고열의 고통을 보이면서, 그옆에는 두명의 어린생명이 닭장같은 병원으로 부터 도망치기위해 발버둥치고 있었다. 그들은  Ebola의 임상실험 결과를 기다리고 있는 환자들이었다.

환자는 투명한 플라스틱 유리를 통해서 가족들과 대화를 할수 있는 정도다. 그환자의 신상은 비밀에 부쳐져 있으며, 신상이 밝혀질 경우 동네 사람들로 부터, "이볼라 전염병자(Ebola infection)로 낙인찍혀 왕따를 당하기 때문이다. 그녀의 아이들역시 점검을 받았으나 현재로서는 통증이 없는 중이다.

이볼라 치료용 백식이 있어서 치사율이 많이 줄어들긴 했다.  그러나 모든 사람들이 걱정하는것은, '만약에 이여인이  Ebola환자가 아니라면? 또는 만약에 그여인이 "질병 X"로 판명될 확율이 전연없다해도, 만약에 그질병이  Covid-19처럼 신속히 전세계를 점령할수있는 새로운 병으로 알려질수있는 "질병 X"로 알려진다면,  치사율은 이볼라 치사율이 50%에서 90%로 치명적이 될수있다는 것이다.

이상황은 과학적 가상을 말하는게 아니고,  과학적으로 바라보는 팩트를 기준으로 봤을때 과학적 으로 매우 두려움이크다는 점이다. 

"우리는 지금 너무도 두렵기만 하다.   Ebola에 대해 알려진게 전연없다.  Covid에대해서도 아는게 전연없다. 그래서 우리 의사들, 과학자들은 새로운 질병발생에 대해 두려워 하지 않을수 없다"라고 환자를 돌보고있는 닥터 Dadin Bonkole씨는 설명한다.

우리 인간은 알려지지 않은 새로운 아니면 치명적인 바이러스들이 아프리카의 열대림에서 창궐하여 위협하고 있는 상황에 직면해 있다라고  Jean-Jacques Muyembe Tamfum교수는 설명하고 있는데, 그는 1976년에  Ebola바이러스를 발견하는데 많은 도움을 준 과학자로, 그때부터 현재까지도 새로운 전염병균을 찾아내는데 앞장서고 있다.

"우리는 현재 새로운 병원균들이 끝없이 발생하는 세상에 살고있다. 그병원체들이 우리 인류를 지금 커다란 위협속으로 몰아넣고 있다"라고 그는  CNN과의 대담에서 상황설명을 했다.

콩고공화국의 수도  Kinshasa에서  CNN과 독점 인터뷰를 하면서,  닥터  Muyembe는 더많은 전염병이 동물을( zoonotic diseases)매개체로 해서 전염될것을 경고했다. 그병원균들은 동물로 부터 우리 인간에게 전염되는 것이라고 한다. 여러종류의

황열병(Yellow fever),  여러종류의 인플루엔자, 광견병, 브루셀라병, 라임병( Lyme disease )들이 동물로 부터 우리 인간에게 옮겨오는 병들로, 때로는 큰쥐 또는 곤충같은 매개체를 통해서 발병한다고 경고한다. 그러한 매개체들이 과거에 epidemics과 pandemics으로 우리를 무서움에 떨게한 전염병 원인제공자들이었었다. 

많은 과학자들은  Ebola가 발생하여 우리 인간들을 급습한 원인을 열대우림과 연결시켜고 있다. 2017년 연구에 따르면, 많은 과학자들이 인공위성 데이타를 이용하여 조사한후 결론내기를, 2001년부터 2014년 사이에 아프리카의 중앙과 서부지역에서 발병한 27개의  Ebola중 25개는 열대림 지역의 경계지역안에서 발생했는데,  이지역은 전염병 발생 2년전에 벌목을 했던적이 있었다.

과학자들은 설명하기를 동물매개체를 통한  Ebola의 발생은 주로 인구밀도가 많은 지역에서 주로 발생했는데, 그런지역에서는 바이러스가 왕성하게 활동하기에 좋은 조건을 갖추었기 때문이라고 설명했다. 그러나 열대우림숲의 벌목과도 연관이 있는것으로 보고 있다고 한다.

21세기에 접어 들면서, 처음 14년동안에, Bangladesh보다 더넓은 지역이 콩고강유역의 열대우림속으로 사라졌다고 과학자들은 설명이다.

시간이 흐를수록 알지 못하는 전염병은 계속 발병할것으로, 그래서 과학자들이 더 걱정을 많이 하고 있는것으로 이해되지만, 여전히 오늘도 벌목은 계속되고 있고, 지구는 계속해서 병들어 가고 있다.  


In the Congo rainforest, the doctor who discovered Ebola warns of deadly viruses yet to come.

Kinshasa, Democratic Republic of the Congo — Showing early symptoms of hemorrhagic fever, the patient sits quietly on her bed, wrangling two toddlers desperate to flee the cell-like hospital room in Ingende, a remote town in the Democratic Republic of the Congo (DRC).
They are waiting for the results of a test for Ebola.
The patient can only communicate with her relatives through a clear plastic observation window. Her identity is secret, to protect her from being ostracized by locals fearful of Ebola infection. Her children have also been tested but, for now, show no symptoms.
There is a vaccine and a treatment for Ebola, which have brought down the rate at which it kills.
But the question at the back of everyone's mind is: What if this woman doesn't have Ebola? What if, instead, she is patient zero of "Disease X," the first known infection of a new pathogen that could sweep the world as fast as Covid-19, but one that has Ebola's 50% to 90% fatality rate?
Doctor Dadin Bonkole works at the Ingende Hospital's Ebola Red Zone.
This isn't the stuff of science fiction. It's a scientific fear, based on scientific facts.
    "We've all got to be frightened," the patient's physician, Dr. Dadin Bonkole, said. "Ebola was unknown. Covid was unknown. We have to be afraid of new diseases."

    Threat to humanity

    Humanity faces an unknown number of new and potentially fatal viruses emerging from Africa's tropical rainforests, according to Professor Jean-Jacques Muyembe Tamfum, who helped discover the Ebola virus in 1976 and has been on the frontline of the hunt for new pathogens ever since.
    "We are now in a world where new pathogens will come out," he told CNN. "And that's what constitutes a threat for humanity."
    As a young researcher, Muyembe took the first blood samples from the victims of a mysterious disease that caused hemorrhages and killed about 88% of patients and 80% of the staff who were working at the Yambuku Mission Hospital when the disease was first discovered.
    The vials of blood were sent to Belgium and the US, where scientists found a worm-shaped virus. They called it "Ebola," after the river close to the outbreak in the country that was then known as Zaire.
    The identification of Ebola relied on a chain that connected the most remote parts of Africa's rainforests to high-tech laboratories in the West.
    Now, the West must rely on African scientists in the Congo and elsewhere to act as the sentinels to warn against future diseases.
    In Ingende, the fears of encountering a new, deadly, virus remained very real even after the recovery of the patient showing symptoms that looked like Ebola. Her samples were tested on site and sent on to the Congo's National Institute of Biomedical Research (INRB) in Kinshasa, where they were further tested for other diseases with similar symptoms. All came back negative, the illness that affected her remains a mystery.
      Speaking exclusively to CNN in the DRC's capital, Kinshasa, Muyembe warned of many more zoonotic diseases -- those that jump from animals to humans -- to come.
      Yellow fever, various forms of influenza, rabies, brucellosis and Lyme disease are among those that pass from animals to humans, often via a vector such as a rodent or an insect.
      They've caused epidemics and pandemics before.
      HIV emerged from a type of chimpanzee and mutated into a world-wide modern plague. SARS, MERS and the Covid-19 virus known as SARS-CoV-2 are all coronaviruses that jumped to humans from unknown "reservoirs" -- the term virologists use for virus' natural hosts -- in the animal kingdom. Covid-19 is thought to have originated in China, possibly in bats.
      Does Muyembe think future pandemics could be worse than Covid-19, more apocalyptic? "Yes, yes, I think so," he said.

      New viruses on the rise

      Since the first animal-to-human infection, yellow fever, was identified in 1901, scientists have found at least another 200 viruses known to cause disease in humans. According to research by Mark Woolhouse, professor of infectious disease epidemiology at the University of Edinburgh, new species of viruses are being discovered at a rate of three to four a year. The majority of them originate from animals.
      Experts say the rising number of emerging viruses is largely the result of ecological destruction and wildlife trade.
      As their natural habitats disappear, animals like rats, bats, and insects survive where larger animals get wiped out. They're able to live alongside human beings and are frequently suspected of being the vectors that can carry new diseases to humans.
      A passenger boat stops for a break on the shores of Ingende. These boats can take weeks to make their way down-river to Kinshasa.
      Scientists have linked past Ebola outbreaks to heavy human incursion into the rainforest. In one 2017 study, researchers used satellite data to determine that 25 of the 27 Ebola outbreaks located along the limits of the rainforest biome in Central and West Africa between 2001 and 2014 began in places that had experienced deforestation about two years prior. They added that zoonotic Ebola outbreaks appeared in areas where human population density was high and where the virus has favorable conditions, but that the relative importance of forest loss is partially independent of these factors.
        In the first 14 years of the 21st century, an area larger than the size of Bangladesh was felled in the Congo River basin rainforest.
        The United Nations has warned that if the current deforestation and population growth trends continue, the country's rainforest may have completely disappeared by the end of the century. As that happens, animals and the viruses they carry will collide with people in new and often disastrous ways.
        It doesn't have to be this way.
        multidisciplinary group of scientists based across the US, China, Kenya and Brazil has calculated that a global investment of $30 billion a year into projects to protect rainforests, halt the wildlife trade and farming would be enough to offset the cost of preventing future pandemics.
        Writing in the journal Science, the group said spending $9.6 billion a year on global forest protection schemes could lead to a 40% reduction in global deforestation in areas at the highest risk of virus spillover. This could include incentivizing the people living in and making their living from the forests, and banning widespread logging and the commercialization of the wildlife trade.
        A similar program in Brazil led to a 70% decline in deforestation between 2005 and 2012, the scientists said.
        While $30 billion a year may sound like a lot, scientists argue that the investment would quickly pay for itself. The coronavirus pandemic will cost the US alone an estimated $16 trillion over the next 10 years, according to Harvard economists David Cutler and Larry Summers, the former US Treasury Secretary. The IMF estimates that globally, the pandemic will cost $28 trillion in lost output between 2020 and 2025, relative to pre-pandemic projections.

          The early warning system

          Muyembe now runs the INRB in Kinshasa.
          While some scientists still sit in the cramped offices in the old INRB compound where Muyembe first worked on Ebola, brand-new laboratories opened in February. The INRB is supported by Japan, the US, the World Health Organization, the EU and other international donors including NGOs, foundations and academic institutions
          With Biosafety Level 3 labs, genome sequencing capability and world-class equipment, these facilities are not an act of charitable aid -- they're a strategic investment
          Backed by the US Centers for Disease Control and Prevention and the World Health Organization, these INRB labs are the world's early warning system for new outbreaks of known diseases like Ebola, and -- perhaps more importantly -- for those illnesses we have yet to discover.
          "If a pathogen emerged from Africa it will take time to spread all over the world," Muyembe said. "So, if this virus is detected early -- like in my institution here -- there will be opportunity for Europe [and the rest of the world] to develop new strategies to fight these new pathogens."
          Muyembe has reconnaissance units on the frontline of the war against new pathogens. Doctors, virologists and researchers are working deep in the DRC's interior, seeking out known and unknown viruses before they can cause new pandemics.
          Simon Pierre Ndimbo and Guy Midingi are ecologists and virus hunters in the DRC's northwestern Équateur Province, where Ingende is located. They're the tip of the spear in tracking and tracing signs of emerging infectious diseases (EIDs).
          On a recent expedition the pair collected 84 bats, painstakingly picking them from their nets and tying the squealing, nipping animals up into bags.
          "You have to be careful -- if not, they bite," explained Midingi, his hands double-gloved for protection.
          A single bat bite could be the moment a new disease makes the leap from animals to humans.
          Ndimbo says their priority is to look for signs of Ebola infection in the bats. The latest outbreak of the disease in the Équateur province has been traced to human-to-human transmission but also to a new strain that is asumed so have come from the forest reservoir. And no one knows where, or what, that reservoir is.
          Back at the lab in Mbandaka the bats are swabbed, and blood samples are taken to be tested for Ebola before being sent to the INRB for further tests. The bats are then released.
          Dozens of new coronaviruses have been found in bats over recent years. No one knows just how dangerous they may be to humans.
          At a lab in Mbandaka, ecologists prepare to take a blood sample from a bat captured in the forest.
          Exactly how Ebola first infected humans remains a mystery, but scientists believe zoonotic illnesses like Ebola and Covid-19 make the leap when wild animals are butchered.
          So-called "bushmeat" is the traditional source of protein for people living in the rainforests, but it is now traded far from where it's sourced and exported globally. The UN estimates that as much as 5 million tons of bushmeat are taken from the Congo River basin each year.
          In Kinshasa, a market trader brandishes the smoked carcass of a colobus monkey, its teeth exposed in a gruesome, petrified grin -- he's selling the small primates for $22, though the price, he says, is "negotiable."
          Colobus monkeys have been hunted to extinction in some parts of the DRC, but the trader says he could export scores of them to Europe by plane.
          "I have to be honest, it's forbidden to send the monkeys," he explains. "We have to cut their heads and arms off and pack them among the other meats."
          He says he gets deliveries every week, often from Ingende, around 400 miles upriver -- the same village where doctors live in fear of a new pandemic emerging.
          Adams Cassinga, CEO of Conserv Congo and a wildlife crime investigator, said investigations have shown that "in Kinshasa alone, we have between five and 15 tons of bushmeat exported ... some goes to the Americas ... but the biggest part goes to Europe. Mainly to Brussels, Paris and London."
          Smoked monkeys, soot-blackened sections of python, and fly-blown hams of sitatunga, a water-dwelling antelope, are gruesome. But they're unlikely to be carrying dangerous viruses, which would be killed by the cooking process -- although scientists have warned that even cooked primate meat is not completely safe.
          The live animals in the so-called "wet" market pose a bigger threat.
          Here young crocodiles -- snouts wired shut and legs tied up -- writhe on top of one another. Traders offer barrels of giant land snails, tortoises and freshwater turtles. Elsewhere there are black markets from live chimpanzees, and more exotic animals, some traded into private collections, others heading for the pot.
          "Disease X" may be ticking away inside any one of these animals, brought to the metropolis by poor people serving the tastes of the rich for exotic meals and pets.
          Bushmeat market in Kinshasa Port. Smoked fish is for sale here.
          "Bushmeat here, in urban areas, unlike the popular misconception, it is not for the poor, it is for the rich and privileged, so you've got high-ranking officials who believe in superstition that if you consume a certain type of bushmeat, it will give you strength," Cassinga said. "You also have people who consume it as a symbol of status. But also in the last 10 to 20 years we have experienced an influx of expatriates, mainly from Southeast Asia, and who demand to eat certain types of meat such as turtles, snakes, primates."
          Scientists have previously linked these kinds of wet markets to zoonotic diseases. The H5N1 influenza virus, known as the avian flu, and SARS both emerged from them. The exact origin of the coronavirus that causes Covid-19 has not been confirmed. But the greatest suspicion for its source has fallen on "wet" markets where live animals are sold and butchered for meat.
          The commercialization of the bushmeat trade is a potential route for infection. It's also a symptom of the devastation of the Congo tropical rainforest, the world's second largest after the Amazon.
          Most of the destruction is driven by local farmers, who rely on the forest economically -- 84% of forest clearance is to make room for small scale agriculture.
          Yet the slash and burn techniques used by the locals increase human exposure to this once-virgin territory and its wild animals, a major risk factor for disease.
          "If you go in the forest ... you will change the ecology; and insects and rats will leave this place and come to the villages ... so this is the transmission of the virus, of the new pathogens," Muyembe said.
          Back in Ingende Hospital, the doctors are wearing as much protective gear as can be found: Goggles, yellow biohazard overalls, double gloves taped shut, hoods over their heads and shoulders, galoshes over their shoes, and complex facemasks.
          They are still worried that the female patient may be showing symptoms of an Ebola-like illness that is not, in fact, Ebola. It may be a new virus, it may also be one of the many diseases that afflict people here that are already known to science -- but none of the tests done here have explained her high fever and diarrhea.
          "We get cases which look very much like Ebola, but then when we do the tests, they are negative," said the head of medical services in Ingende, Dr. Christian Bompalanga.
          "We have to carry out additional examinations in order to see what is really going on ... at the moment there are a couple of suspected cases over there," he added, pointing to the isolation ward where the young woman and her kids are being treated. And weeks later there remains no clear diagnosis for her illness.
          Once a new virus begins circulating among humans, the consequences of a brief encounter at the edge of a forest or at a wet market could be devastating. Covid-19 has shown that. Ebola has proved it. And in most of the scientific publications there is an assumption that there will be more contagions coming as humans continue to destroy wilderness habitats. It's not an "IF" it's a "WHEN".
          The solution is clear. Protect the forests to protect humanity -- because Mother Nature has deadly weapons in her armory.

          https://www.cnn.com/2020/12/22/africa/drc-forest-new-virus-intl/index.html

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