The Health Ministry of Guinea, Médecins Sans Frontières (MSF), Epicentre and The Norwegian Institute of Public Health (NIPH), will launch a phase III trial in Guinea on March 7 to test the VSV-EBOV vaccine; they hope to find that it successfully prevents Ebola transmission.

A second Ebola vaccine is also lined up for study as soon as supplies become readily available, the World Health Organization (WHO) reported. Since September 2014, the two most promising Ebola vaccines have been evaluated in about 15 countries in Africa, Europe and North America in a rapid testing strategy that aims to get provide widespread protection against the deadly disease as soon as possible.

"We have worked hard to reach this point," said WHO Director-General, Dr. Margaret Chan. "There has been massive mobilization on the part of the affected countries and all partners to accelerate the development and availability of proven interventions. If a vaccine is found effective, it will be the first preventive tool against Ebola in history."

After successful initial trials, the researchers will not be testing the effectiveness of the vaccine on individuals in Basse Guinée, which currently has the highest number of Ebola cases in the country. The researchers will use the "ring vaccination" approach that was used to eradicate smallpox in the 1970s. In this approach all of the "contacts" of someone who has been recently diagnosed with Ebola are quickly vaccinated. This type of vaccination strategy aims to determine if the vaccine protects the individuals, and if they create a "buffer" around the infected person to hinder the spread of the disease.

"The Ebola epidemic shows signs of receding but we cannot let down our guard until we reach zero cases," said Assistant Director-General Marie-Paule Kieny, who leads the Ebola Research and Development effort at WHO. "An effective vaccine to control current flare-ups could be the game-changer to finally end this epidemic and an insurance policy for any future ones."