Since March, the number of cases of Ebola in West Africa has soared, with more than 1,711 cases of Ebola reported in Guinea, Liberia, and Sierra Leone, in what is considered the largest Ebola outbreak in history.

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. Ebola causes fever, headaches, vomiting, diarrhea, and internal bleeding. And there are still no drugs or vaccines approved to treat or prevent the illness. Currently, doctors can only treat symptoms.

Ebola is a highly contagious disease spread by contact with an infected person’s bodily fluids. The infection is spreading in West Africa, where, as of this writing, it has killed 932 people since the outbreak began in March. According to the World Health Organization, from August 2 to August 4, a total of 108 new cases of EVD (laboratory-confirmed, probable, and suspect cases) as well as 45 deaths were reported from Guinea, Liberia, Nigeria, and Sierra Leone.

Sheik Umar Khan, a Sierra Leone doctor who treated more than 100 Ebola patients, recently died from the condition.

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Two American healthcare workers, Dr. Kent Brantly, from Texas, and Nancy Writebol, from North Carolina, who were working at a hospital caring for Ebola patients in Monrovia, Liberia, on a joint Samaritan’s Purse Organization Service In Mission (SIM), were infected with Ebola. They were flown to Emory University Hospital in Atlanta, where they are being treated and monitored in an isolation unit. Brantly arrived at Emory August 2, and Writebol arrived three days later. Writebol’s condition was reported as very serious when she arrived in Atlanta. Brantly and Writebol are currently both reportedly showing signs of improvement.

While still in Liberia, Brantly and Writebol were given an experimental antibody cocktail, called ZMAPP. According to a Bloomberg report, ZMAPP was developed by Mapp Biopharmaceutical in San Diego. A limited amount of the drug was sent at sub-zero temperatures from Kentucky BioProcessing, a subsidiary of Reynolds American, which makes the treatment from tobacco plants. It is not known whether the drug is responsible for their improved condition.

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Currently, Ebola patients receive supportive care, including intravenous fluids, and blood and platelet transfusions. Now a human Ebola vaccine looks promising.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases (NIAID), said in a CBS This Morning interview that the National Institutes of Health (NIH) is slated to begin a human vaccine trial in September 2014. The vaccine could be in production by January, and ready by next July. “We tested it in monkeys; it looks very good. It protects monkeys completely from challenge with Ebola. They don’t get sick and they don’t die, whereas unvaccinated monkeys all do,” said Fauci, in the report.

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NIAID Vaccine Research Center developed the vaccine, and it has shown promise in a primate model. The vaccine does not contain any of the pathogens that cause the Ebola virus. It is a chimpanzee adenovirus vector vaccine that has incorporated two Ebola virus genes. The vaccine works by entering a cell and delivering the new genetic material. The new genes that are inserted cause a protein to become expressed, which in turn produces an immune response in the body.

In another development, the Centers for Disease Control and Prevention (CDC) tested blood from a man who recently returned from West Africa with symptoms consistent with Ebola. He was hospitalized and placed in isolation at Mount Sinai Hospital in New York. It has been confirmed that he does not have the Ebola virus.