Ebola virus disease (EVD), also known as Ebola hemorrhagic fever, has a 90 percent fatality rate. It is one of the most virulent viral diseases known to humankind. And there are still no drugs or vaccines approved to treat or prevent the illness. Currently, doctors can only treat symptoms.

While outbreaks in the past decade have been confined to the Congo, the Republic of Congo, and Uganda, with the exception of one outbreak in Sudan in 2004, the deadly virus is rearing its ugly head in a new country—Guinea—and spreading beyond those borders.  

As of this writing, a total of four people in neighboring Liberia and Sierra Leone are thought to have contracted EVD, and an estimated 80 people have died.

According to the World Health Organization (WHO), this is the worst outbreak in seven years.

Ebola is characterized by the sudden onset of fever, intense weakness, muscle pain, headache, and sore throat. This is followed by vomiting, diarrhea, rash, impaired kidney and liver function, and, in some cases, both internal and external bleeding. Laboratory findings include low white blood cell and platelet counts and elevated liver enzymes

With an eye toward stopping the deadly virus from spreading, Senegal has closed its normally busy border with Guinea after confirmation that the virus had reached Conakry, Guinea's capital.

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Most Aggressive and Deadly Strain

According to Doctors Without Borders, or Médecins Sans Frontières (MSF), this outbreak is of the Zaire strain of the virus, which is the most aggressive and deadly strain.

"We are facing an epidemic of a magnitude never before seen in terms of the distribution of cases in the country,” Mariano Lugli, coordinator of MSF's project in Conakry, said in a press release.

MSF announced that it will have about 60 international field workers experienced with addressing EVD, in both Conakry and in the southeast of the country, by the end of this week. Doctors, nurses, epidemiologists, water and sanitation experts, and anthropologists will be on hand. In addition, more than 40 tons of equipment have been sent to the country to try to stop the disease from spreading, according to MSF.

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How Is Ebola Transmitted?

Ebola is transmitted by direct contact with the blood, body fluids, and tissues of infected persons, as well as by handling sick or dead infected wild animals, such as chimpanzees, gorillas, monkeys, forest antelope, and fruit bats. Healthcare workers have frequently been infected while treating patients with suspected or confirmed EVD.

According to WHO, people are infectious as long as their blood and secretions contain the virus. Ebola virus was isolated from semen 61 days after onset of illness in a man who was infected in a laboratory. The incubation period, that is, the time interval from infection with the virus to onset of symptoms, is 2 to 21 days.

The Ministry of Health of Liberia is communicating regularly with WHO and neighboring countries to help coordinate surveillance, prevention, and control activities. Liberia has formed a high-level National Task Force to lead the response. Response partners include WHO, the International Red Cross (IRC), UNICEF, and other international and local organizations.

Currently, WHO has not recommended that any travel or trade restrictions be applied to Liberia, Guinea. or Sierra Leone based on the current information available.

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Should We Be Worried About Ebola?

Dr. Kenneth Mayer, a visiting professor at Harvard Medical School and the medical research director at Boston’s Fenway Institute, told Healthline, “The virus is highly infectious and can be transmitted via a respiratory route, which is why it is concerning, but the hosts for the infection are not present in North America, so there is no reason for alarm here."

Paul L. Doering, M.S., emeritus distinguished service professor of pharmacotherapy and translational research, University of Florida College of Pharmacy, also weighed in, telling Healthline, “Yes, there should be concern.”

He added, “With Ebola, they pretty much know what the virus is, but there is no known effective treatment and there is no vaccine. There is also no specific antiviral treatment. It is a very scary disease.... It must be extremely frustrating for healthcare workers, who must feel helpless and are forced to witness horrible death after horrible death.”

On a more reassuring note, Doering said, “I assure you that the best minds in the world in the infectious disease community are feverishly at work trying to figure out how it is spread and how to stop the spread.”

Ian Lipkin, the John Snow Professor of Epidemiology at Columbia University's Mailman School of Public Health in New York City, told National Geographic that EVD is often spread by a ritual behavior in which people wash bodies by hand to prepare them for burial, as a loving way of sending the spirit into the next world. This brings those people into very close contact with infected body fluids. “Typically, these outbreaks are relatively easy to control if you can get people to stop washing dead bodies.”

So even if a vaccine were developed, could it work against Ebola? Lipkin explained to National Geographic that you don't generally vaccinate people for something that doesn't occur commonly, and that even if you have an effective vaccine, there's always a potential risk associated with using vaccines.

Instead, Lipkin said the answer lies in bringing treatment online when people have been infected. “There's a lot of emphasis on therapeutic antibodies from people who've survived infection, which could create instant immunization, or drugs that can prevent the virus from replicating,” he said.

He is hopeful that international groups like MSF will come in and “cordon off the area, use a variety of diagnostic tests to exclude the worried well from truly sick, and try to interfere with some of these funeral practices.”

Photo courtesy of Kjell Gunnar Beraas/MSF.