(CNN) – That's how the fear sounds.
No buzzing banter and gossip, no sputtering of yellow and white taxis or Boda Boda taxis. No gum or hip-hop music from the market stalls.
Just a terrible silence.
It was August 4, 2014, and the government of Sierra Leone had ordered more than 7 million citizens to enter and pray. The Ebola epidemic was out of control, and it was time for desperate measures.
Government officials knew that the shutdown would not slow down the spread, but they wanted to dissuade the entire population from taking notice of it. They performed temperature checks on roadblocks, isolation departments and emergency burial teams, all to stop dying.
The disease would continue to challenge more than 1
Ebola is now stalking another part of Africa.  Since early May, scientists, epidemiologists and doctors have been fighting an outbreak of the virus in the Democratic Republic of the Congo, the ninth to have been seen in the country.
"We're getting ready for the worst The answer to that The epidemic is on the cutting edge," Dr. Peter Salama, head of the World Health Organization's Health Emergencies Program.
This time – and for the first time in 40 years fighting Ebola – global health experts (19659002) Armed with an experimental vaccine and empowered by a revolution in global health security introduced after the disaster of the West African epidemic, they believe That they have a real chance to eradicate Ebola's deadly menace
Forty years of struggle
"There are two defining epidemics of our time: the AIDS epidemic and Ebola," said Peter Piot, director of the London School of Hygiene and Tropical Medicine.
The acclaimed microbiologist has been instrumental in fighting both diseases. He founded the executive director of UNAIDS and discovered the Ebola virus, which originated 40 years ago in the Democratic Republic of the Congo, then in Zaire and today's South Sudan.
In August 1976 director of the Yambuku School of Mission in the province of Équateur in the ambulance of the Catholic Mission with chills and fever, led by Belgian nuns. He had just made a two-week road trip north to the border of the Central African Republic, where he had bought smoked monkey meat.
He was first treated for malaria and returned home. But the director came back a week later with a cascade of more serious symptoms. In early September he died of profound bleeding.
More patients came soon, and the nuns unintentionally spread Mystery Disease through dirty needles.
A broken vial of blood from one of the infected nuns finally arrived at the Institute of Tropical Medicine Antwerp in Belgium, where Piot worked. He and his fellow scientists did not recognize the virus.
Piot was immediately dispatched to Yambuku, the youngest member of a team of scientists investigating the mysterious outbreak.
"I've never been out of Africa in my life or in Africa, so I was not really qualified, but there were no other candidates," he said.
The symptoms he found were appalling. The patients bled from the inside out.
Ebola first hits the immune system, forms clots throughout the body, and causes an immune system to "storm", which attacks all the vital organs of the body and causes massive internal bleeding.
In the last stages, patients bleed from their eyes.
There are several strains of the Ebola virus. The Zaire tribe, in whose identification Piot was involved, can kill up to 90% of the infected, based on a history of outbreaks.
Piot and his colleagues called this new form of hemorrhagic Ebola virus disease after the nearby Ebola River. a tributary of the Congo River
The team stopped the outbreak in Yambuku by tracking contacts of suspect cases and each severely isolated, showing symptoms, a technique that was used for hundreds of years. Of the 318 suspected cases, 280 died.
Piot recalls how he drove straight from the field to an emergency meeting at the Tropical Medicine School in London, which he would one day lead. He says WHO and donor countries promised immediate investments.
"We'll never let that happen again," they said. Of course, what happened? Nothing, "said Piot.
But it happened again – and again … And then there was 2014.
Like this first outbreak in 1976, the West African epidemic had modest, if tragic, origins.
Seven months before Sierra Leone shut down the land, the eruption began with an 18-month outbreak Young Emile in neighboring Guinea
Scientists from WHO and Guinea believe that Emile found the Ebola virus of bats near his home in the remote village He died and passed the disease on to his closest family.
From then on, the virus infected more victims, secretly, by sick workers and traditional burial practices, where mourners bathed the dead, failing health systems and international complacency crept into Ebola quickly across borders and into cities.
"Even after several months, a lot of talk and little was done "said Stefan Kruger, Doctors Without Borders) doctor who was stationed in a treatment center in Sierra Leone. "This could make the spread of the virus out of control."
The world finally took notice of when US Ebola patients showed up in US hospitals in isolation chambers, flanked by doctors in "space suits."
The Outlook A global pandemic triggered global action.
The WHO and foreign governments, according to their own statements and devastating independent investigations into the Ebola reaction, were aware of the threat far too late.
When WHO declared the outbreak for 2016 The last toll was devastating.
There were officially 28,616 suspected cases in the West African epidemic and 11,310 deaths, although field doctors say the death toll is likely to be much higher. Today there are more than 20,000 Ebola orphans in West Africa.
Sierra Leone, Guinea and Liberia lost more than $ 2 billion in economic growth in 2015 alone, according to the World Bank.
Breakthrough – but too late
19659013] Some form of vaccine development for Ebola has been in the works for decades, but a dreadful virus that plagued limited people in remote parts of the world did not provide sufficient stimulus to wealthy countries and pharmaceutical countries for investment.
"For many highly dangerous pathogens that hit developing countries, and especially in this case sub-Saharan Africa, it is very difficult to find an interest from manufacturers in the market, as there is no lucrative market for these products," said Salama 
Prior to the outbreak of West Africa, Ebola was not as dangerous to health authorities as influenza, which causes up to 646,000 deaths per year by the US Centers. D Isease Control and Prevention
Another caveat was the fact that vaccine development for a virus like Ebola can only be done in selected four-safety laboratories. Just to look at it through a microscope, scientists have to be in pressure suits.
But both Piot and Salama agree that the threat of Ebola required vaccination – and one that could have come much sooner.
As tragic as it was, the magnitude of the epidemic in 2014 is forcing governments, WHO and pharmaceutical companies to take more seriously emerging pathogens – diseases that have recently emerged or recently spread throughout the population ,
The most promising The experimental Ebola vaccine was accelerated to production and tested late in the outbreak in West Africa. The study proved to be extremely effective, with one study demonstrating 100% efficacy
Canadian government scientists developed the vaccine in the mid-2000s, now called rVSV-ZEBOV.
In simple words, the vaccines with the VSV virus simulate an immune response in the body to the Ebola virus.
"The team used advanced technology to deliver the outer envelope of the Ebola virus into the benign VSV virus, and with additional modifications, it basically gave it ebola makeup," Dr. Guillaume Poliquin, Senior Medical Advisor to the Public Health Agency of Canada at the National Microbiology Lab.
Merck is now producing the vaccine in large quantities.
A booster-style vaccine that could provide even longer protection is also in advanced stages of development by Johnson & Johnson. It has been tested on thousands of volunteers.
For the first time in the face of an outbreak, doctors can give real hope to Ebola patients and their families.
Detective work in the forest
In a sense, the Congo eruption is eerily similar to the early stages of the West African eruption.
The disease is spreading in the densely forested northwest of the country near the borders of the Central African Republic and the Republic of Congo – and similarly in West Africa, the risk of a regional epidemic is very real.
The first recorded cases of the eruption came from the remote wooded area of Bikoro, but soon spread to Mbandaka, an important port city and a regional gateway. Ebola could spread along the Congo and increase the prospects of an outbreak in the capital, Kinshasa, with more than 10 million inhabitants.
But unlike the countries affected in 2014, the Congo has been proven to be successful in fighting Ebola outbreaks
"We have been involved with Ebola since 1976, so we have developed the expertise and speed to respond to these outbreaks to respond, "said Dr. Oly Ilunga Kalenga, Minister of Health of the country.
Your teams must be as many detectives as there are health workers.
In order to curb the spread, the contacts of each suspicious case are exhaustively monitored and monitored. In the urban environment the contacts are exponentially higher, but in the deep forest they are much harder to find.
Doctors in the Congo say they are not even close to the stage of controlling the outbreak. You must first track the chains of transmission.
The single-dose experimental vaccine has been used and injected into health workers – often the most vulnerable – and is fanned out with the help of a vaccination campaign in which contacts of cases are made, and then their contacts are vaccinated in ever-increasing rings, to eradicate the spread.
The ring vaccination strategy was used in the 1970s against smallpox until it was officially eradicated in 1980.
But in the Congo this will be the case an enormous logistical challenge.
Airlifts and Motorcycles
The vaccine needs to be stored at minus 70 degrees Celsius, so an airlift was built connecting the planes with UN choppers and then motorcycles then combing through the single lane forest roads in the epicenter of the outbreak.
The speed with which the WHO has responded shows a major paradigm shift from 2014. Just days after the announcement of Ebola, thousands of doses of the va ccine were in the country.
"You are not waiting for the first Western person to get sick and say, 'Oh my God, we need to activate the emergency. "This is a big change," said Luis Encinas, a physician at Medecin's Sans Frontieres, who works in the epicenter of northwest Congo.
Compared to 2014, global powers, UN agencies and affected countries appear to be taking on their role in global health security Seriously, experts agree
"We are very aware of our position and our role in the global health security agenda", said Kalenga, the Minister of Health, who personally led the vaccination campaign.
But it is still early in this outbreak, and much could go wrong, as was the case of two patients who have fled this week from isolation in Mbandaka and died – perhaps a new chain of transmission in the city.  Salama says workers still need to convince local people that health workers, often from head to toe in appalling protective gear, are there to help.
"There are always two epidemics: one of the virus and one of fear," he said
] CORRECTION: This story is bee • updated to reflect that the Democratic Republic of Congo once referred to as Zaire
The CNN Wire
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