( CNN ) After months racing not only to treat Ebola but to find ways to prevent it , health authorities will launch a vaccination campaign Saturday in one of the areas that has been most devastated by the disease . The trial , using vaccines developed by the Public Health Agency of Canada , will be administered in Basse Guinee , a region that has had the highest number of Ebola cases in Guinea . Another vaccine will be tested in a subsequent study , according to a press release from the World Health Organization , Medecins Sans Frontieres ( Doctors Without Borders ) , and the Norwegian Institute of Public Health . `` We have worked hard to reach this point , '' WHO Director-General Dr. Margaret Chan said . `` ... If a vaccine is found effective , it will be the first preventive tool against Ebola in history . '' Patient Zero -- i.e . the first case in the current Ebola outbreak -- is thought to be a 2-year-old Guinean boy who contracted the virus in December 2013 and died a few days later . Since then , the vast majority of the more than 23,900 cases and more than 9,800 deaths reported by WHO have come in Guinea and neighboring Liberia and Sierra Leone . There are new Ebola cases every day , including 132 in the last week of February ( which is up from 99 reported the previous week ) . While Liberia did n't have any of these new incidences , Guinea did -- especially in Forecariah and Conakry . Still , authorities in Africa and their partners around the world have had significant successes generally in combating the deadly disease . The progress -- as measured in the rate of new cases , with January 's incidences being the lowest in seven months -- has been so significant that health authorities ' focus has shifted from slowing the spread to ending the epidemic . This positive movement has come as a result of steps like better disease control , public awareness campaigns and attention to burial practices . But the tool that has been used to eradicate many other contagious diseases -- vaccines -- has been elusive . That 's why , over the past six months , WHO has been working with scientists , ethicists and policymakers to try to create both better treatment therapies and a vaccine that will stop people for getting Ebola in the first place . Health workers in the Guinea trial will start with a new Ebola case and then trace all of that patient 's contacts , giving each of them the option of getting vaccinated . John-Arne Rottingen , from the Norwegian Institute of Public Health , said this program is happening at the request of Guinean authorities and called the participation of residents there `` vital '' to its success . `` The Ebola epidemic shows signs of receding but we can not let our guard down until we reach zero cases , '' WHO official Marie-Paule Kieny said . `` 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 . ''
WHO leader : This vaccine could be `` the first preventive tool against Ebola in history '' and it is being developed by a team of scientists from around the world. Authorities have had success in curbing Ebola , but dozens of new cases still arise each week .